Volatile organic compound reducer and method for reducing volatile organic compounds

Abstract

The present invention provides a volatile organic compound decreasing agent with which it is possible to decrease the amount of diffusion of a volatile organic compound. A volatile organic compound decreasing agent according to the present invention contains amino acids as an active ingredient, and thus, when to-be-treated objects such as building materials, interior materials for transportation devices, and daily commodities are treated with the volatile organic compound decreasing agent, it is possible to trap volatile organic compounds included in the to-be-treated objects and to mostly prevent the volatile organic compounds from being diffused into the atmosphere, and accordingly, to prevent sick house syndrome or the like in advance.

Description

Technical Field

[0001] The present invention relates to a reducing agent for volatile organic compounds and a method for reducing volatile organic compounds.

Background Art

[0002] Conventionally, organic materials have been used as construction materials for building structures and components such as vehicles. High heat insulation and high airtightness have been achieved for the purpose of energy saving and improvement of the quietness inside the vehicle.

[0003] On the other hand, since volatile organic compounds (VOCs, Volatile Organic Compounds) released from organic materials used in components such as building materials and vehicles cause sick house syndrome, attempts have been made to reduce the amount of volatile organic compounds released from components such as building materials and vehicles.

[0004] Patent Document 1 discloses a method for removing volatile organic compounds, which includes a step of decomposing volatile organic compounds using a photocatalyst and a step of capturing the substances generated by the decomposition step with a capturing substance.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the reduction of volatile organic compounds by the above method for removing volatile organic compounds is insufficient, and further reduction of volatile organic compounds is required.

[0007] The present invention provides a reducing agent for volatile organic compounds capable of reducing the emission amount of volatile organic compounds, and a method for reducing volatile organic compounds using the same.

Means for Solving the Problems

[0008] The reducing agent for volatile organic compounds of the present invention is characterized by containing an amino acid as an active ingredient.

Effects of the Invention

[0009] The reducing agent for volatile organic compounds of the present invention exhibits an excellent effect of reducing volatile organic compounds.

Modes for Carrying Out the Invention

[0010] The reducing agent for volatile organic compounds of the present invention contains an amino acid as an active ingredient.

[0011] (Amino acid) The reducing agent for volatile organic compounds contains an amino acid as an active ingredient. The inventor has found that an amino acid can be used as an active ingredient for reducing volatile organic compounds. The reducing agent for volatile organic compounds contains an amino acid. The reducing agent for volatile organic compounds contains an amino acid as an active ingredient.

[0012] The content of amino acid in the volatile organic compound reducing agent is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, more preferably 0.5% by mass or more, more preferably 1% by mass or more, more preferably 2% by mass or more, more preferably 3% by mass or more, more preferably 4% by mass or more, more preferably 5% by mass or more, more preferably 6% by mass or more, more preferably 7% by mass or more, more preferably 8% by mass or more, more preferably 9% by mass or more, preferably 10% by mass or more, more preferably 15% by mass or more, more preferably 20% by mass or more, more preferably 25% by mass or more, more preferably 30% by mass or more, more preferably 35% by mass or more, more preferably 40% by mass or more, more preferably 45% by mass or more, more preferably 50% by mass or more, more preferably 55% by mass or more, more preferably 60% by mass or more, more preferably 70% by mass or more, and particularly preferably 80% by mass or more because the volatile organic compound reducing effect exerted by the volatile organic compound reducing agent is improved.

[0013] The content of amino acid in the volatile organic compound reducing agent is preferably 100% by mass or less, more preferably 99% by mass or less, more preferably 98% by mass or less, more preferably 97% by mass or less, more preferably 96% by mass or less, more preferably 95% by mass or less, more preferably 90% by mass or less, more preferably 85% by mass or less, and more preferably 80% by mass or less.

[0014] The volatile organic compound reducing agent can remove the volatile organic compound until the concentration of the volatile organic compound becomes low. According to the volatile organic compound reducing agent, preferably, the volatile organic compound can be reduced to 2% by mass or less (more preferably 1% by mass or less, more preferably 0.5% by mass or less, and particularly preferably 0.3% by mass or less) of the initial amount of the volatile organic compound. According to the volatile organic compound reducing agent, preferably, the volatile organic compound can be reduced to 2% by volume or less (more preferably 1% by volume or less, more preferably 0.5% by volume or less, and particularly preferably 0.3% by volume or less) of the initial amount of the volatile organic compound.

[0015] According to the volatile organic compound reducer, after removing volatile organic compounds by absorption or the like, the removed volatile organic compounds are hardly discharged from the volatile organic compound reducer, and the volatile organic compounds can be stably removed over time, achieving the reduction of volatile organic compounds. The volatile organic compound reducer can be particularly preferably used for reducing aldehydes, amine compounds, fatty acids, and alcohols, and more preferably used for reducing aldehydes, amine compounds, and fatty acids.

[0016] Note that the volatile organic compound refers to an organic compound that has volatility and becomes gaseous in the atmosphere. Examples of volatile organic compounds include aldehydes (e.g., formaldehyde, acetaldehyde, benzaldehyde, propionaldehyde, etc.), amine compounds (e.g., ammonia, trimethylamine, indole, etc.), fatty acids (e.g., acetic acid, isovaleric acid, etc.), sulfur compounds (hydrogen sulfide, methyl mercaptan), alcohols (2-propanol, hexanol, nonenal, dibutyl phthalate, 2-ethylhexyl phthalate), etc.

[0017] Amino acids include compounds having an amino group (-NH2) and a carboxyl group (-COOH) in the molecule, as well as imino acids (e.g., proline, hydroxyproline, etc.) in which the amino group and the side chain portion in the molecule form a cyclic structure. As amino acids, α-amino acids in which the amino group and the carboxyl group are bonded to the same carbon atom are preferred. In addition, amino acids include salts and hydrates of amino acids. Examples of salts of amino acids include hydrochloride, sulfate, nitrate, acetate, phosphate, metal salts (e.g., sodium salt, potassium salt, lithium salt, calcium salt, zinc salt, etc.), toluenesulfonate, methanesulfonate, etc., and hydrochloride of amino acids is preferred. Examples of hydrates of amino acids include monohydrates of amino acids. Note that amino acids can be used alone or in combination of two or more.

[0018] Examples of amino acids include hydrophilic amino acids, hydrophobic amino acids, and special amino acids. Examples of hydrophilic amino acids include basic hydrophilic amino acids, acidic hydrophilic amino acids, and neutral hydrophilic amino acids, and acidic hydrophilic amino acids and neutral hydrophilic amino acids are preferred.

[0019] Examples of basic hydrophilic amino acids include lysine, arginine, arginine hydrochloride, histidine, etc. Examples of acidic hydrophilic amino acids include aspartic acid, glutamic acid, etc. Examples of neutral hydrophilic amino acids include serine, threonine, asparagine, glutamine, etc.

[0020] Hydrophobic amino acids include aliphatic hydrophobic amino acids, aromatic hydrophobic amino acids, and sulfur-containing hydrophobic amino acids.

[0021] Examples of aliphatic hydrophobic amino acids include branched-chain aliphatic hydrophobic amino acids such as valine, isoleucine, and leucine, and aliphatic hydrophobic amino acids without branched chains such as alanine and glycine, and aliphatic hydrophobic amino acids without branched chains are preferred. In the aliphatic hydrophobic amino acid without a branched chain, "without a branched chain" means that the carbon atoms constituting the side chain portion bonded to the carbon atom to which the amino group and / or carboxyl group is bonded are composed of only primary carbon atoms and / or secondary carbon atoms. The above side chain portion may be a hydrogen atom. That is, "without a branched chain" means that the side chain portion bonded to the carbon atom to which the amino group or carboxyl group is bonded is linear or a hydrogen atom.

[0022] Examples of aromatic hydrophobic amino acids include phenylalanine, tyrosine, tryptophan, etc.

[0023] Examples of sulfur-containing hydrophobic amino acids include methionine, cysteine, salts of cysteine (preferably cysteine hydrochloride), cystine, etc. Cysteine and salts of cysteine are preferred, cysteine and cysteine hydrochloride are more preferred, and cysteine hydrochloride is even more preferred.

[0024] Examples of special amino acids include proline, hydroxyproline, etc.

[0025] The content of aliphatic hydrophobic amino acids in the amino acid is preferably 10 - 90% by mass, more preferably 15 - 85% by mass, even more preferably 20 - 80% by mass, still more preferably 30 - 70% by mass, and most preferably 40 - 60% by mass. The content of aliphatic hydrophobic amino acids in the amino acid is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, still more preferably 30% by mass or more, and most preferably 40% by mass or more. The content of aliphatic hydrophobic amino acids in the amino acid is preferably 90% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less, still more preferably 70% by mass or less, and most preferably 60% by mass or less. When the content of aliphatic hydrophobic amino acids is within the above range, the effect of reducing volatile organic compounds is improved.

[0026] The content of alanine in the amino acid is preferably 3 - 50% by mass, more preferably 5 - 45% by mass, even more preferably 6 - 43% by mass, still more preferably 7 - 42% by mass, most preferably 10 - 40% by mass, more preferably 15 - 35% by mass, and particularly preferably 20 - 30% by mass. The content of alanine in the amino acid is preferably 3% by mass or more, more preferably 5% by mass or more, even more preferably 6% by mass or more, still more preferably 7% by mass or more, and most preferably 10% by mass or more. The content of alanine in the amino acid is preferably 50% by mass or less, more preferably 45% by mass or less, even more preferably 43% by mass or less, still more preferably 42% by mass or less, most preferably 40% by mass or less, more preferably 35% by mass or less, and particularly preferably 30% by mass or less. When the content of alanine is within the above range, the effect of reducing volatile organic compounds is improved.

[0027] The content of glycine in the amino acid is preferably 3 to 50% by mass, more preferably 5 to 45% by mass, still more preferably 6 to 43% by mass, yet more preferably 7 to 42% by mass, still more preferably 10 to 40% by mass, still more preferably 15 to 35% by mass, and particularly preferably 20 to 30% by mass. The content of glycine in the amino acid is preferably 3% by mass or more, more preferably 5% by mass or more, still more preferably 6% by mass or more, yet more preferably 7% by mass or more, and still more preferably 10% by mass or more. The content of glycine in the amino acid is preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 43% by mass or less, yet more preferably 42% by mass or less, still more preferably 40% by mass or less, still more preferably 35% by mass or less, and still more preferably 30% by mass or less. When the content of glycine is within the above range, the effect of reducing volatile organic compounds is improved.

[0028] In the amino acid, the content of sulfur-containing hydrophobic amino acids is preferably 10 to 90% by mass, more preferably 15 to 85% by mass, still more preferably 20 to 80% by mass, yet more preferably 30 to 70% by mass, and still more preferably 40 to 60% by mass. The content of sulfur-containing hydrophobic amino acids in the amino acid is preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, yet more preferably 30% by mass or more, and still more preferably 40% by mass or more. The content of sulfur-containing hydrophobic amino acids in the amino acid is preferably 90% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less, yet more preferably 70% by mass or less, and still more preferably 60% by mass or less. When the content of sulfur-containing hydrophobic amino acids is within the above range, the effect of reducing volatile organic compounds is improved.

[0029] In the amino acid, the cysteine content is preferably 10 to 90% by mass, more preferably 15 to 85% by mass, still more preferably 20 to 80% by mass, still more preferably 30 to 70% by mass, and still more preferably 40 to 60% by mass. The cysteine content in the amino acid is preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, still more preferably 30% by mass or more, and still more preferably 40% by mass or more. The cysteine content in the amino acid is preferably 90% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less, still more preferably 70% by mass or less, and still more preferably 60% by mass or less. When the cysteine content is within the above range, the effect of reducing volatile organic compounds is improved.

[0030] In the amino acid, the content of the cysteine salt is preferably 10 to 90% by mass, more preferably 15 to 85% by mass, still more preferably 20 to 80% by mass, still more preferably 30 to 70% by mass, and still more preferably 40 to 60% by mass. The content of the cysteine salt in the amino acid is preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, still more preferably 30% by mass or more, and still more preferably 40% by mass or more. The content of the cysteine salt in the amino acid is preferably 90% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less, still more preferably 70% by mass or less, and still more preferably 60% by mass or less. When the cysteine salt content is within the above range, the effect of reducing volatile organic compounds is improved.

[0031] The amino acid preferably contains an aliphatic hydrophobic amino acid and a sulfur-containing hydrophobic amino acid, and more preferably contains an aliphatic hydrophobic amino acid and a sulfur-containing hydrophobic amino acid that do not contain a branched chain. The amino acid preferably contains alanine, glycine, and cysteine. The amino acid preferably contains a salt of alanine, glycine, and cysteine, and more preferably contains alanine, glycine, and cysteine hydrochloride.

[0032] When the amino acid contains aliphatic hydrophobic amino acids and sulfur-containing hydrophobic amino acids, the content of aliphatic hydrophobic amino acids in the amino acid is preferably 10 to 90% by mass, more preferably 15 to 85% by mass, still more preferably 20 to 80% by mass, more preferably 30 to 70% by mass, and even more preferably 40 to 60% by mass. The content of aliphatic hydrophobic amino acids in the amino acid is preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more. The content of aliphatic hydrophobic amino acids in the amino acid is preferably 90% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less. When the content of aliphatic hydrophobic amino acids is within the above range, the effect of reducing volatile organic compounds is improved.

[0033] When the amino acid contains aliphatic hydrophobic amino acids and sulfur-containing hydrophobic amino acids, the content of sulfur-containing hydrophobic amino acids in the amino acid is preferably 10 to 90% by mass, more preferably 15 to 85% by mass, still more preferably 20 to 80% by mass, more preferably 30 to 70% by mass, and even more preferably 40 to 60% by mass. The content of sulfur-containing hydrophobic amino acids in the amino acid is preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more. The content of sulfur-containing hydrophobic amino acids in the amino acid is preferably 90% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less. When the content of sulfur-containing hydrophobic amino acids is within the above range, the effect of reducing volatile organic compounds is improved.

[0034] When the amino acid contains aliphatic hydrophobic amino acids and sulfur-containing hydrophobic amino acids, the aliphatic hydrophobic amino acids in the amino acid preferably contain alanine and glycine. In this case, the content of alanine in the amino acid is preferably 3 to 50% by mass, more preferably 5 to 45% by mass, still more preferably 6 to 43% by mass, still more preferably 7 to 42% by mass, still more preferably 10 to 40% by mass, still more preferably 15 to 35% by mass, and particularly preferably 20 to 30% by mass. The content of alanine in the amino acid is preferably 3% by mass or more, more preferably 5% by mass or more, still more preferably 6% by mass or more, still more preferably 7% by mass or more, and still more preferably 10% by mass or more. The content of alanine in the amino acid is preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 43% by mass or less, still more preferably 42% by mass or less, still more preferably 40% by mass or less, still more preferably 35% by mass or less, and still more preferably 30% by mass or less. Similarly, the content of glycine in the amino acid is preferably 3 to 50% by mass, more preferably 5 to 45% by mass, still more preferably 6 to 43% by mass, still more preferably 7 to 42% by mass, still more preferably 10 to 40% by mass, still more preferably 15 to 35% by mass, and particularly preferably 20 to 30% by mass. The content of glycine in the amino acid is preferably 3% by mass or more, more preferably 5% by mass or more, still more preferably 6% by mass or more, still more preferably 7% by mass or more, and still more preferably 10% by mass or more. The content of glycine in the amino acid is preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 43% by mass or less, still more preferably 42% by mass or less, still more preferably 40% by mass or less, still more preferably 35% by mass or less, and still more preferably 30% by mass or less. When the contents of alanine and glycine are within the above ranges, the effect of reducing volatile organic compounds is improved.

[0035] When the amino acid contains aliphatic hydrophobic amino acids and sulfur-containing hydrophobic amino acids, the sulfur-containing hydrophobic amino acid in the amino acid preferably contains cysteine or a salt of cysteine, more preferably contains a salt of cysteine, and even more preferably contains cysteine hydrochloride. The content of cysteine in the amino acid is preferably 10 to 90% by mass, more preferably 15 to 85% by mass, even more preferably 20 to 80% by mass, still more preferably 30 to 70% by mass, and even more preferably 40 to 60% by mass. The content of cysteine in the amino acid is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, still more preferably 30% by mass or more, and even more preferably 40% by mass or more. The content of cysteine in the amino acid is preferably 90% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less, still more preferably 70% by mass or less, and even more preferably 60% by mass or less. The content of the salt of cysteine in the amino acid is preferably 10 to 90% by mass, more preferably 15 to 85% by mass, even more preferably 20 to 80% by mass, still more preferably 30 to 70% by mass, and even more preferably 40 to 60% by mass. The content of the salt of cysteine in the amino acid is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, still more preferably 30% by mass or more, and even more preferably 40% by mass or more. The content of the salt of cysteine in the amino acid is preferably 90% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less, still more preferably 70% by mass or less, and even more preferably 60% by mass or less. When the contents of cysteine and the salt of cysteine are within the above ranges, the effect of reducing volatile organic compounds is improved.

[0036] (sulfur compound) The volatile organic compound reducing agent preferably contains a sulfur compound. When the volatile organic compound reducing agent contains a sulfur compound, the reduction or removal of the volatile organic compound by the volatile organic compound reducing agent can be carried out in a short time.

[0037] A sulfur compound refers to a compound containing a sulfur atom. The sulfur compound is not particularly limited, and examples thereof include sulfites (e.g., sodium sulfite, potassium sulfite, calcium sulfite, magnesium sulfite, calcium sulfite, ammonium sulfite, etc.), bisulfites (e.g., sodium bisulfite, potassium bisulfite, calcium bisulfite, etc.), pyrosulfites (sodium pyrosulfite, potassium pyrosulfite, calcium pyrosulfite, etc.), hyposulfites (sodium hyposulfite, potassium hyposulfite, calcium hyposulfite, etc.), thiosulfates (sodium thiosulfate, potassium thiosulfate, calcium thiosulfate, etc.). The sulfur compound may be used alone or in combination of two or more.

[0038] Since the sulfur compound can reduce or remove volatile organic compounds by a reducing agent for volatile organic compounds in a short time, sulfites, bisulfites and pyrosulfites are preferred, alkali metal salts of sulfurous acid, alkaline earth metal salts of sulfurous acid, alkali metal salts of bisulfurous acid, alkaline earth metal salts of bisulfurous acid are more preferred, alkali metal salts of sulfurous acid, alkaline earth metal salts of sulfurous acid, sodium bisulfite, potassium bisulfite, calcium bisulfite, sodium pyrosulfite, potassium pyrosulfite, calcium pyrosulfite are more preferred, alkali metal salts of sulfurous acid, sodium bisulfite, potassium bisulfite, sodium pyrosulfite, potassium pyrosulfite are more preferred, sodium sulfite (Na2SO3), sodium bisulfite (NaHSO3), sodium pyrosulfite (Na2S2O5), potassium pyrosulfite (K2S2O5) are more preferred, and sodium sulfite and sodium bisulfite are more preferred. Since the sulfur compound can reduce or remove volatile organic compounds by a reducing agent for volatile organic compounds in a short time, it is preferably contained with sulfites and bisulfites, more preferably contained with alkali metal salts of sulfurous acid and bisulfites, and more preferably contained with alkali metal salts of sulfurous acid and alkali metal salts of bisulfurous acid.

[0039] The content of the sulfur compound in the volatile organic compound reducing agent is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 40 parts by mass or more, more preferably 50 parts by mass or more, more preferably 60 parts by mass or more, more preferably 70 parts by mass or more, more preferably 80 parts by mass or more, more preferably 90 parts by mass or more, more preferably 100 parts by mass or more, more preferably 110 parts by mass or more, more preferably 120 parts by mass or more, and more preferably 130 parts by mass or more with respect to 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing the volatile organic compound is improved. The reduction or removal of the volatile organic compound by the volatile organic compound reducing agent can be carried out in a short time.

[0040] The content of the sulfur compound in the volatile organic compound reducing agent is preferably 3000 parts by mass or less, more preferably 2900 parts by mass or less, more preferably 2800 parts by mass or less, more preferably 2700 parts by mass or less, more preferably 2600 parts by mass or less, more preferably 2500 parts by mass or less, more preferably 2400 parts by mass or less, more preferably 2300 parts by mass or less, more preferably 2200 parts by mass or less, more preferably 2100 parts by mass or less, more preferably 2000 parts by mass or less, more preferably 1900 parts by mass or less, more preferably 1800 parts by mass or less, more preferably 1700 parts by mass or less, more preferably 1600 parts by mass or less, more preferably 1500 parts by mass or less, more preferably 1400 parts by mass or less, more preferably 1300 parts by mass or less, more preferably 1200 parts by mass or less, more preferably 1100 parts by mass or less, more preferably 1000 parts by mass or less, more preferably 950 parts by mass or less, more preferably 900 parts by mass or less, more preferably 850 parts by mass or less, more preferably 800 parts by mass or less, more preferably 750 parts by mass or less, more preferably 700 parts by mass or less, more preferably 650 parts by mass or less, more preferably 600 parts by mass or less, more preferably 550 parts by mass or less, more preferably 500 parts by mass or less, more preferably 450 parts by mass or less, more preferably 400 parts by mass or less, more preferably 350 parts by mass or less, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing the volatile organic compound is improved. The reduction or removal of the volatile organic compound by the volatile organic compound reducing agent can be carried out in a short time.

[0041] When the sulfur compound contains sulfite and bisulfite, the mass ratio of the content of sulfite to the content of bisulfite (content of sulfite / content of bisulfite) is preferably from 0.2 to 5, more preferably from 0.3 to 4.8, still more preferably from 0.5 to 4.5, still more preferably from 0.53 to 4.4, still more preferably from 0.6 to 4.2, still more preferably from 0.7 to 4, still more preferably from 0.8 to 3.7. When the sulfur compound contains sulfite and bisulfite, the mass ratio of the content of sulfite to the content of bisulfite (content of sulfite / content of bisulfite) is preferably 0.2 or more, more preferably 0.3 or more, still more preferably 0.5 or more, still more preferably 0.53 or more, still more preferably 0.6 or more, still more preferably 0.7 or more, still more preferably 0.8 or more. The mass ratio of the content of sulfite to the content of bisulfite (content of sulfite / content of bisulfite) is preferably 5 or less, more preferably 4.8 or less, still more preferably 4.5 or less, still more preferably 4.4 or less, still more preferably 4.2 or less, still more preferably 4 or less, still more preferably 3.7 or less. When the mass ratio of the content of sulfite to the content of bisulfite (content of sulfite / content of bisulfite) is within the above range, the effect of reducing volatile organic compounds is improved.

[0042] When the amino acid is cysteine or a salt of cysteine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 55 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 70 parts by mass or more, more preferably 75 parts by mass or more, more preferably 80 parts by mass or more, more preferably 85 parts by mass or more, more preferably 90 parts by mass or more, more preferably 95 parts by mass or more, more preferably 100 parts by mass or more, and more preferably 105 parts by mass or more with respect to 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of cysteine or a salt of cysteine (when including cysteine and a salt of cysteine, the total content of cysteine and a salt of cysteine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0043] When the amino acid is cysteine or a salt of cysteine, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,500 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,700 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,500 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,300 parts by mass or less, more preferably 1,200 parts by mass or less, more preferably 1,100 parts by mass or less, more preferably 1,050 parts by mass or less, more preferably 800 parts by mass or less, more preferably 700 parts by mass or less, more preferably 600 parts by mass or less, more preferably 500 parts by mass or less, more preferably 450 parts by mass or less, more preferably 400 parts by mass or less, more preferably 350 parts by mass or less, more preferably 300 parts by mass or less, more preferably 250 parts by mass or less, more preferably 180 parts by mass or less, more preferably 170 parts by mass or less, more preferably 150 parts by mass or less, more preferably 140 parts by mass or less, more preferably 130 parts by mass or less, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing the volatile organic compound is improved. The reduction or removal of the volatile organic compound by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of cysteine or a salt of cysteine (when including cysteine and a salt of cysteine, the total content of cysteine and a salt of cysteine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0044] When the amino acid is cysteine or a salt of cysteine, the effect of reducing volatile organic compounds is improved. Therefore, as the sulfur compound, bisulfite and sulfite are preferred, alkali metal bisulfites, alkaline earth metal bisulfites, alkali metal sulfites and alkaline earth metal sulfites are more preferred, and sodium bisulfite and sodium sulfite are even more preferred. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of cysteine or a salt of cysteine (when cysteine and a salt of cysteine are included, the total content of cysteine and a salt of cysteine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more), the same applies.

[0045] When the amino acid is phenylalanine or a salt of phenylalanine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, even more preferably 30 parts by mass or more, even more preferably 35 parts by mass or more, even more preferably 40 parts by mass or more, even more preferably 45 parts by mass or more, even more preferably 55 parts by mass or more, even more preferably 60 parts by mass or more, even more preferably 75 parts by mass or more, even more preferably 80 parts by mass or more, even more preferably 85 parts by mass or more, even more preferably 90 parts by mass or more, even more preferably 95 parts by mass or more, even more preferably 100 parts by mass or more, even more preferably 105 parts by mass or more, even more preferably 107 parts by mass or more, even more preferably 107 parts by mass or more, even more preferably 108 parts by mass or more, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of phenylalanine or a salt of phenylalanine (when phenylalanine and a salt of phenylalanine are included, the total content of phenylalanine and a salt of phenylalanine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more), the same applies.

[0046] When the amino acid is phenylalanine or a salt of phenylalanine, the content of the sulfur compound is preferably 3000 parts by mass or less, more preferably 3000 parts by mass or less, still more preferably 2900 parts by mass or less, still more preferably 2800 parts by mass or less, still more preferably 2700 parts by mass or less, still more preferably 2600 parts by mass or less, still more preferably 2000 parts by mass or less, still more preferably 1900 parts by mass or less, still more preferably 1800 parts by mass or less, still more preferably 1700 parts by mass or less, still more preferably 1600 parts by mass or less, still more preferably 1500 parts by mass or less, still more preferably 1300 parts by mass or less, still more preferably 1200 parts by mass or less, still more preferably 1100 parts by mass or less, still more preferably 1050 parts by mass or less, still more preferably 800 parts by mass or less, still more preferably 700 parts by mass or less, still more preferably 600 parts by mass or less, still more preferably 500 parts by mass or less, still more preferably 450 parts by mass or less, still more preferably 400 parts by mass or less, still more preferably 350 parts by mass or less, still more preferably 300 parts by mass or less, still more preferably 250 parts by mass or less, still more preferably 190 parts by mass or less, still more preferably 180 parts by mass or less, still more preferably 170 parts by mass or less, still more preferably 160 parts by mass or less, still more preferably 150 parts by mass or less, still more preferably 140 parts by mass or less, still more preferably 130 parts by mass or less, still more preferably 120 parts by mass or less, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of phenylalanine or a salt of phenylalanine (when including phenylalanine and a salt of phenylalanine, the total content of phenylalanine and a salt of phenylalanine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more), the same applies.

[0047] When the amino acid is phenylalanine or a salt of phenylalanine, the effect of reducing volatile organic compounds is improved. Therefore, the sulfur compound is preferably a bisulfite, more preferably an alkali metal bisulfite or an alkaline earth metal bisulfite, and even more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of phenylalanine or a salt of phenylalanine (when including phenylalanine and a salt of phenylalanine, the total content of phenylalanine and a salt of phenylalanine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more), the same applies.

[0048] When the amino acid is alanine or a salt of alanine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, even more preferably 25 parts by mass or more, more preferably 35 parts by mass or more, more preferably 37 parts by mass or more, more preferably 40 parts by mass or more, more preferably 43 parts by mass or more, more preferably 45 parts by mass or more, more preferably 47 parts by mass or more, and even more preferably 50 parts by mass or more with respect to 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of alanine or a salt of alanine (when including alanine and a salt of alanine, the total content of alanine and a salt of alanine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more), the same applies.

[0049] When the amino acid is alanine or a salt of alanine, the sulfur compound content is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,700 parts by mass or less, more preferably 2,500 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,500 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,300 parts by mass or less, more preferably 1,200 parts by mass or less, more preferably 1,100 parts by mass or less, more preferably 1,050 parts by mass or less, more preferably 900 parts by mass or less, more preferably 800 parts by mass or less, more preferably 700 parts by mass or less, more preferably 600 parts by mass or less, more preferably 500 parts by mass or less, more preferably 400 parts by mass or less, more preferably 300 parts by mass or less, per 100 parts by mass of the amino acid. When the sulfur compound content is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of alanine or a salt of alanine in the amino acid (when including alanine and a salt of alanine, the total content of alanine and a salt of alanine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more).

[0050] When the amino acid is alanine or a salt of alanine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal bisulfite or an alkaline earth metal bisulfite, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of alanine or a salt of alanine in the amino acid (when including alanine and a salt of alanine, the total content of alanine and a salt of alanine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more).

[0051] When the amino acid is lysine or a salt of lysine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, preferably 30 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 55 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 70 parts by mass or more, more preferably 75 parts by mass or more, more preferably 80 parts by mass or more, more preferably 85 parts by mass or more, more preferably 90 parts by mass or more, more preferably 95 parts by mass or more, more preferably 100 parts by mass or more, more preferably 105 parts by mass or more, more preferably 107 parts by mass or more, more preferably 110 parts by mass or more, more preferably 150 parts by mass or more, more preferably 180 parts by mass or more, more preferably 210 parts by mass or more, more preferably 250 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 500 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 900 parts by mass or more, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of lysine or a salt of lysine (when including lysine and a salt of lysine, the total content of lysine and a salt of lysine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0052] When the amino acid is lysine or a salt of lysine, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, still more preferably 2,700 parts by mass or less, still more preferably 2,600 parts by mass or less, still more preferably 2,500 parts by mass or less, still more preferably 2,400 parts by mass or less, still more preferably 2,300 parts by mass or less, still more preferably 2,200 parts by mass or less, still more preferably 2,100 parts by mass or less, still more preferably 2,000 parts by mass or less, still more preferably 1,900 parts by mass or less, still more preferably 1,800 parts by mass or less, still more preferably 1,700 parts by mass or less, still more preferably 1,600 parts by mass or less, still more preferably 1,500 parts by mass or less, still more preferably 1,400 parts by mass or less, still more preferably 1,300 parts by mass or less, still more preferably 1,200 parts by mass or less, still more preferably 1,100 parts by mass or less, and still more preferably 1,050 parts by mass or less, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of lysine or a salt of lysine (when including lysine and a salt of lysine, the total content of lysine and a salt of lysine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more).

[0053] When the amino acid is lysine or a salt of lysine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal bisulfite or an alkaline earth metal bisulfite, and still more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of lysine or a salt of lysine (when including lysine and a salt of lysine, the total content of lysine and a salt of lysine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more).

[0054] When the amino acid is glycine or a salt of glycine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 35 parts by mass or more, more preferably 37 parts by mass or more, more preferably 39 parts by mass or more, more preferably 41 parts by mass or more, more preferably 43 parts by mass or more, more preferably 45 parts by mass or more, more preferably 47 parts by mass or more, more preferably 49 parts by mass or more, more preferably 120 parts by mass or more, more preferably 130 parts by mass or more, more preferably 140 parts by mass or more, more preferably 150 parts by mass or more, more preferably 160 parts by mass or more, more preferably 170 parts by mass or more, more preferably 180 parts by mass or more, more preferably 190 parts by mass or more, more preferably 210 parts by mass or more, more preferably 250 parts by mass or more, more preferably 300 parts by mass or more, more preferably 350 parts by mass or more, more preferably 400 parts by mass or more, more preferably 450 parts by mass or more, more preferably 500 parts by mass or more, more preferably 550 parts by mass or more, more preferably 600 parts by mass or more, more preferably 650 parts by mass or more, more preferably 700 parts by mass or more, more preferably 750 parts by mass or more, more preferably 800 parts by mass or more, more preferably 850 parts by mass or more, more preferably 900 parts by mass or more, more preferably 950 parts by mass or more, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of glycine or a salt of glycine (when including glycine and a salt of glycine, the total content of glycine and a salt of glycine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0055] When the amino acid is glycine or a salt of glycine, the content of the sulfur compound is preferably 3000 parts by mass or less, more preferably 2800 parts by mass or less, more preferably 2600 parts by mass or less, more preferably 2400 parts by mass or less, more preferably 2200 parts by mass or less, more preferably 2000 parts by mass or less, more preferably 1800 parts by mass or less, more preferably 1600 parts by mass or less, more preferably 1400 parts by mass or less, more preferably 1300 parts by mass or less, more preferably 1200 parts by mass or less, more preferably 1100 parts by mass or less, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of glycine or a salt of glycine (when including glycine and a salt of glycine, the total content of glycine and a salt of glycine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more).

[0056] When the amino acid is glycine or a salt of glycine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal bisulfite or an alkaline earth metal bisulfite, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of glycine or a salt of glycine (when including glycine and a salt of glycine, the total content of glycine and a salt of glycine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more).

[0057] When the amino acid is arginine or a salt of arginine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 40 parts by mass or more, more preferably 50 parts by mass or more, more preferably 60 parts by mass or more, more preferably 70 parts by mass or more, more preferably 80 parts by mass or more, more preferably 85 parts by mass or more, more preferably 90 parts by mass or more, more preferably 95 parts by mass or more, more preferably 100 parts by mass or more, more preferably 110 parts by mass or more, more preferably 120 parts by mass or more, more preferably 130 parts by mass or more, more preferably 140 parts by mass or more, more preferably 150 parts by mass or more, more preferably 160 parts by mass or more, more preferably 170 parts by mass or more, more preferably 180 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 250 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 450 parts by mass or more, more preferably 500 parts by mass or more, more preferably 550 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 750 parts by mass or more, more preferably 800 parts by mass or more, more preferably 850 parts by mass or more, more preferably 900 parts by mass or more, more preferably 950 parts by mass or more, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of arginine or a salt of arginine (when including arginine and a salt of arginine, the total content of arginine and a salt of arginine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0058] When the amino acid is arginine or a salt of arginine, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,600 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,200 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,500 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,300 parts by mass or less, more preferably 1,200 parts by mass or less, more preferably 1,100 parts by mass or less, and more preferably 1,050 parts by mass or less, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of arginine or a salt of arginine (when including arginine and a salt of arginine, the total content of arginine and a salt of arginine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0059] When the amino acid is arginine or a salt of arginine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal bisulfite or an alkaline earth metal bisulfite, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of arginine or a salt of arginine (when including arginine and a salt of arginine, the total content of arginine and a salt of arginine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0060] When the amino acid is glutamic acid or a salt of glutamic acid, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 55 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 90 parts by mass or more, more preferably 95 parts by mass or more, more preferably 100 parts by mass or more, more preferably 105 parts by mass or more, more preferably 107 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 250 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 450 parts by mass or more, more preferably 500 parts by mass or more, more preferably 550 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 750 parts by mass or more, more preferably 800 parts by mass or more, more preferably 850 parts by mass or more, more preferably 900 parts by mass or more, more preferably 950 parts by mass or more, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of glutamic acid or a salt of glutamic acid (when including glutamic acid and a salt of glutamic acid, the total content of glutamic acid and a salt of glutamic acid) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0061] When the amino acid is glutamic acid or a salt of glutamic acid, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,600 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,200 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,700 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,500 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,300 parts by mass or less, more preferably 1,200 parts by mass or less, more preferably 1,100 parts by mass or less, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of glutamic acid or a salt of glutamic acid (when including glutamic acid and a salt of glutamic acid, the total content of glutamic acid and a salt of glutamic acid) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0062] When the amino acid is glutamic acid or a salt of glutamic acid, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal salt of bisulfurous acid or an alkaline earth metal salt of bisulfurous acid, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of glutamic acid or a salt of glutamic acid (when including glutamic acid and a salt of glutamic acid, the total content of glutamic acid and a salt of glutamic acid) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0063] When the amino acid is serine or a salt of serine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 150 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 500 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 900 parts by mass or more, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of serine or a salt of serine (when including serine and a salt of serine, the total content of serine and a salt of serine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more).

[0064] When the amino acid is serine or a salt of serine, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,600 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,200 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,200 parts by mass or less, and even more preferably 1,050 parts by mass or less, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of serine or a salt of serine (when including serine and a salt of serine, the total content of serine and a salt of serine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more).

[0065] When the amino acid is serine or a salt of serine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal bisulfite or an alkaline earth metal bisulfite, and even more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of serine or a salt of serine (when including serine and a salt of serine, the total content of serine and a salt of serine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more).

[0066] When the amino acid is proline or a salt of proline, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 125 parts by mass or more, more preferably 135 parts by mass or more, more preferably 145 parts by mass or more, more preferably 150 parts by mass or more, more preferably 160 parts by mass or more, more preferably 170 parts by mass or more, more preferably 180 parts by mass or more, more preferably 190 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 500 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 900 parts by mass or more, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of proline or a salt of proline (when including proline and a salt of proline, the total content of proline and a salt of proline) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0067] When the amino acid is proline or a salt of proline, the content of the sulfur compound is preferably 3000 parts by mass or less, more preferably 2800 parts by mass or less, more preferably 2600 parts by mass or less, more preferably 2400 parts by mass or less, more preferably 2200 parts by mass or less, more preferably 2000 parts by mass or less, more preferably 1800 parts by mass or less, more preferably 1600 parts by mass or less, more preferably 1400 parts by mass or less, more preferably 1200 parts by mass or less, and more preferably 1050 parts by mass or less, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of proline or a salt of proline (when including proline and a salt of proline, the total content of proline and a salt of proline) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0068] When the amino acid is proline or a salt of proline, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal salt of bisulfurous acid or an alkaline earth metal salt of bisulfurous acid, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of proline or a salt of proline (when including proline and a salt of proline, the total content of proline and a salt of proline) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0069] When the amino acid is aspartic acid or a salt of aspartic acid, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 125 parts by mass or more, more preferably 135 parts by mass or more, more preferably 145 parts by mass or more, more preferably 150 parts by mass or more, more preferably 160 parts by mass or more, more preferably 170 parts by mass or more, more preferably 180 parts by mass or more, more preferably 190 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 500 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 900 parts by mass or more, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of aspartic acid or a salt of aspartic acid (when including aspartic acid and a salt of aspartic acid, the total content of aspartic acid and a salt of aspartic acid) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0070] When the amino acid is aspartic acid or a salt of aspartic acid, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,600 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,200 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,200 parts by mass or less, and more preferably 1,050 parts by mass or less, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of aspartic acid or a salt of aspartic acid (when including aspartic acid and a salt of aspartic acid, the total content of aspartic acid and a salt of aspartic acid) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0071] When the amino acid is aspartic acid or a salt of aspartic acid, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal salt of bisulfurous acid or an alkaline earth metal salt of bisulfurous acid, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of aspartic acid or a salt of aspartic acid (when including aspartic acid and a salt of aspartic acid, the total content of aspartic acid and a salt of aspartic acid) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0072] When the amino acid is asparagine or a salt of asparagine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 125 parts by mass or more, more preferably 135 parts by mass or more, more preferably 145 parts by mass or more, more preferably 150 parts by mass or more, more preferably 160 parts by mass or more, more preferably 170 parts by mass or more, more preferably 180 parts by mass or more, more preferably 190 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 500 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 900 parts by mass or more, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of asparagine or a salt of asparagine (when including asparagine and a salt of asparagine, the total content of asparagine and a salt of asparagine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0073] When the amino acid is asparagine or a salt of asparagine, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,600 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,200 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,200 parts by mass or less, and more preferably 1,050 parts by mass or less, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of asparagine or a salt of asparagine (when including asparagine and a salt of asparagine, the total content of asparagine and a salt of asparagine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0074] When the amino acid is asparagine or a salt of asparagine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal salt of bisulfurous acid or an alkaline earth metal salt of bisulfurous acid, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of asparagine or a salt of asparagine (when including asparagine and a salt of asparagine, the total content of asparagine and a salt of asparagine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0075] When the amino acid is arginine hydrochloride, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, more preferably 20 parts by mass or more, more preferably 25 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 50 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 125 parts by mass or more, more preferably 135 parts by mass or more, more preferably 145 parts by mass or more, more preferably 155 parts by mass or more, more preferably 165 parts by mass or more, more preferably 175 parts by mass or more, more preferably 185 parts by mass or more, more preferably 195 parts by mass or more, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of arginine hydrochloride in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more).

[0076] When the amino acid is arginine hydrochloride, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, still more preferably 2,600 parts by mass or less, still more preferably 2,400 parts by mass or less, still more preferably 2,200 parts by mass or less, still more preferably 2,000 parts by mass or less, still more preferably 1,800 parts by mass or less, still more preferably 1,600 parts by mass or less, still more preferably 1,400 parts by mass or less, still more preferably 1,200 parts by mass or less, still more preferably 1,050 parts by mass or less, still more preferably 900 parts by mass or less, still more preferably 800 parts by mass or less, still more preferably 700 parts by mass or less, still more preferably 600 parts by mass or less, still more preferably 500 parts by mass or less, still more preferably 400 parts by mass or less, still more preferably 300 parts by mass or less, and still more preferably 250 parts by mass or less, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of arginine hydrochloride in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more).

[0077] When the amino acid is arginine hydrochloride, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal bisulfite or an alkaline earth metal bisulfite, and still more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of arginine hydrochloride in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more).

[0078] When the amino acid is glutamine or a salt of glutamine, the sulfur compound content is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, more preferably 20 parts by mass or more, more preferably 25 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 50 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 125 parts by mass or more, more preferably 135 parts by mass or more, more preferably 145 parts by mass or more, more preferably 155 parts by mass or more, more preferably 165 parts by mass or more, more preferably 175 parts by mass or more, more preferably 185 parts by mass or more, more preferably 195 parts by mass or more, more preferably 210 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 500 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 900 parts by mass or more, per 100 parts by mass of the amino acid. When the sulfur compound content is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of glutamine or a salt of glutamine (when including glutamine and a salt of glutamine, the total content of glutamine and a salt of glutamine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0079] When the amino acid is glutamine or a salt of glutamine, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,600 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,200 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,200 parts by mass or less, and more preferably 1,050 parts by mass or less, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of glutamine or a salt of glutamine (when including glutamine and a salt of glutamine, the total content of glutamine and a salt of glutamine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0080] When the amino acid is glutamine or a salt of glutamine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal salt of bisulfurous acid or an alkaline earth metal salt of bisulfurous acid, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of glutamine or a salt of glutamine (when including glutamine and a salt of glutamine, the total content of glutamine and a salt of glutamine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0081] When the amino acid is isoleucine or a salt of isoleucine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, still more preferably 20 parts by mass or more, still more preferably 25 parts by mass or more, still more preferably 30 parts by mass or more, still more preferably 35 parts by mass or more, still more preferably 40 parts by mass or more, still more preferably 45 parts by mass or more, still more preferably 50 parts by mass or more, still more preferably 60 parts by mass or more, still more preferably 65 parts by mass or more, still more preferably 75 parts by mass or more, still more preferably 85 parts by mass or more, still more preferably 95 parts by mass or more, and still more preferably 105 parts by mass or more, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of isoleucine or a salt of isoleucine (when including isoleucine and a salt of isoleucine, the total content of isoleucine and a salt of isoleucine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more).

[0082] When the amino acid is isoleucine or a salt of isoleucine, the content of the sulfur compound is preferably 3000 parts by mass or less, more preferably 2800 parts by mass or less, more preferably 2600 parts by mass or less, more preferably 2400 parts by mass or less, more preferably 2200 parts by mass or less, more preferably 2000 parts by mass or less, more preferably 1800 parts by mass or less, more preferably 1600 parts by mass or less, more preferably 1400 parts by mass or less, more preferably 1200 parts by mass or less, more preferably 1050 parts by mass or less, more preferably 900 parts by mass or less, more preferably 800 parts by mass or less, more preferably 700 parts by mass or less, more preferably 600 parts by mass or less, more preferably 500 parts by mass or less, more preferably 400 parts by mass or less, more preferably 300 parts by mass or less, more preferably 250 parts by mass or less, more preferably 180 parts by mass or less, more preferably 150 parts by mass or less, more preferably 140 parts by mass or less, more preferably 130 parts by mass or less, more preferably 120 parts by mass or less, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of isoleucine or a salt of isoleucine (when including isoleucine and a salt of isoleucine, the total content of isoleucine and a salt of isoleucine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more).

[0083] When the amino acid is isoleucine or a salt of isoleucine, the effect of reducing volatile organic compounds is improved. Therefore, the sulfur compound is preferably a bisulfite, more preferably an alkali metal salt of bisulfurous acid or an alkaline earth metal salt of bisulfurous acid, and even more preferably sodium bisulfite. The volatile organic compounds can be reduced or removed by the volatile organic compound reducing agent in a short time. In the amino acid, when the content of isoleucine or a salt of isoleucine (when including isoleucine and a salt of isoleucine, the total content of isoleucine and a salt of isoleucine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more), the same applies.

[0084] When the amino acid is threonine or a salt of threonine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 125 parts by mass or more, more preferably 135 parts by mass or more, more preferably 145 parts by mass or more, more preferably 150 parts by mass or more, more preferably 160 parts by mass or more, more preferably 170 parts by mass or more, more preferably 180 parts by mass or more, more preferably 190 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 500 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 900 parts by mass or more, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of threonine or a salt of threonine (when including threonine and a salt of threonine, the total content of threonine and a salt of threonine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0085] When the amino acid is threonine or a salt of threonine, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,600 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,200 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,200 parts by mass or less, and more preferably 1,050 parts by mass or less with respect to 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of threonine or a salt of threonine (when including threonine and a salt of threonine, the total content of threonine and a salt of threonine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0086] When the amino acid is threonine or a salt of threonine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal salt of bisulfurous acid or an alkaline earth metal salt of bisulfurous acid, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of threonine or a salt of threonine (when including threonine and a salt of threonine, the total content of threonine and a salt of threonine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0087] When the amino acid is leucine or a salt of leucine, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 90 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 125 parts by mass or more, more preferably 135 parts by mass or more, more preferably 145 parts by mass or more, more preferably 150 parts by mass or more, more preferably 160 parts by mass or more, more preferably 170 parts by mass or more, more preferably 180 parts by mass or more, more preferably 190 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 300 parts by mass or more, more preferably 400 parts by mass or more, more preferably 500 parts by mass or more, more preferably 600 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 900 parts by mass or more, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. In the amino acid, when the content of leucine or a salt of leucine (when including leucine and a salt of leucine, the total content of leucine and a salt of leucine) exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0088] When the amino acid is leucine or a salt of leucine, the content of the sulfur compound is preferably 3000 parts by mass or less, more preferably 2800 parts by mass or less, more preferably 2600 parts by mass or less, more preferably 2400 parts by mass or less, more preferably 2200 parts by mass or less, more preferably 2000 parts by mass or less, more preferably 1800 parts by mass or less, more preferably 1600 parts by mass or less, more preferably 1400 parts by mass or less, more preferably 1200 parts by mass or less, and more preferably 1050 parts by mass or less, per 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of leucine or a salt of leucine (when leucine and a salt of leucine are included, the total content of leucine and a salt of leucine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0089] When the amino acid is leucine or a salt of leucine, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal salt of bisulfurous acid or an alkaline earth metal salt of bisulfurous acid, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of leucine or a salt of leucine (when leucine and a salt of leucine are included, the total content of leucine and a salt of leucine) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0090] When the amino acid is tryptophan or a salt of tryptophan, the content of the sulfur compound is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, more preferably 30 parts by mass or more, more preferably 35 parts by mass or more, more preferably 40 parts by mass or more, more preferably 45 parts by mass or more, more preferably 60 parts by mass or more, more preferably 65 parts by mass or more, more preferably 75 parts by mass or more, more preferably 85 parts by mass or more, more preferably 90 parts by mass or more, more preferably 95 parts by mass or more, more preferably 105 parts by mass or more, more preferably 115 parts by mass or more, more preferably 125 parts by mass or more, more preferably 135 parts by mass or more, more preferably 145 parts by mass or more, more preferably 150 parts by mass or more, more preferably 160 parts by mass or more, more preferably 170 parts by mass or more, more preferably 180 parts by mass or more, more preferably 190 parts by mass or more, more preferably 210 parts by mass or more, more preferably 220 parts by mass or more, more preferably 300 parts by mass or more, more preferably 350 parts by mass or more, more preferably 400 parts by mass or more, more preferably 450 parts by mass or more, more preferably 500 parts by mass or more, more preferably 550 parts by mass or more, more preferably 600 parts by mass or more, more preferably 650 parts by mass or more, more preferably 700 parts by mass or more, more preferably 800 parts by mass or more, more preferably 850 parts by mass or more, more preferably 900 parts by mass or more, more preferably 950 parts by mass or more, based on 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. When the content of tryptophan or a salt of tryptophan (when including tryptophan and a salt of tryptophan, the total content of tryptophan and a salt of tryptophan) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more), the same applies.

[0091] When the amino acid is tryptophan or a salt of tryptophan, the content of the sulfur compound is preferably 3,000 parts by mass or less, more preferably 2,800 parts by mass or less, more preferably 2,600 parts by mass or less, more preferably 2,400 parts by mass or less, more preferably 2,200 parts by mass or less, more preferably 2,000 parts by mass or less, more preferably 1,800 parts by mass or less, more preferably 1,600 parts by mass or less, more preferably 1,500 parts by mass or less, more preferably 1,400 parts by mass or less, more preferably 1,300 parts by mass or less, more preferably 1,200 parts by mass or less, more preferably 1,100 parts by mass or less, and more preferably 1,050 parts by mass or less with respect to 100 parts by mass of the amino acid. When the content of the sulfur compound is within the above range, the effect of reducing volatile organic compounds is improved. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of tryptophan or a salt of tryptophan (when including tryptophan and a salt of tryptophan, the total content of tryptophan and a salt of tryptophan) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0092] When the amino acid is tryptophan or a salt of tryptophan, since the effect of reducing volatile organic compounds is improved, the sulfur compound is preferably a bisulfite, more preferably an alkali metal bisulfite or an alkaline earth metal bisulfite, and more preferably sodium bisulfite. The reduction or removal of volatile organic compounds by the volatile organic compound reducing agent can be carried out in a short time. The same applies when the content of tryptophan or a salt of tryptophan (when including tryptophan and a salt of tryptophan, the total content of tryptophan and a salt of tryptophan) in the amino acid exceeds 50% by mass (preferably 70% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more).

[0093] (Alkaline compound) The volatile organic compound reducing agent preferably contains an alkaline compound. By containing an alkaline compound, the volatile organic compound reducing agent can exhibit the effect of reducing volatile organic compounds while maintaining the appearance of the object to be treated. Furthermore, by adjusting the pH of the volatile organic compound reducing agent to be near neutral (preferably 6 to 8, more preferably 6.5 to 7.5), damage to the object to be treated to which the volatile organic compound reducing agent is applied can be reduced, and the appearance of the object to be treated can be maintained.

[0094] An alkaline compound is a compound that forms an alkaline aqueous solution when dissolved in water.

[0095] Examples of the alkaline compound include hydroxides, carbonates, hydrogen carbonates, tertiary phosphates, secondary phosphates, metasilicates, orthosilicates, etc. of alkali metals or alkaline earth metals, and hydroxides, carbonates, tertiary phosphates, metasilicates, orthosilicates of alkaline earth metals are preferred. The alkaline compound may be used alone or in combination of two or more.

[0096] The alkaline compound may be one or more compounds selected from the group consisting of lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, beryllium hydroxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, radium hydroxide, lithium carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, potassium carbonate, potassium hydrogen carbonate, sodium hydrogen carbonate, lithium hydrogen carbonate, trisodium phosphate, tripotassium phosphate, disodium phosphate, dipotassium phosphate, sodium metasilicate, potassium metasilicate, sodium orthosilicate and potassium orthosilicate.

[0097] As the alkaline compound, calcium hydroxide, potassium tertiary phosphate, sodium tertiary phosphate, sodium metasilicate, potassium metasilicate, sodium orthosilicate, and potassium orthosilicate are preferable, calcium hydroxide, potassium tertiary phosphate, sodium metasilicate, and sodium orthosilicate are more preferable, and calcium hydroxide, potassium tertiary phosphate, and sodium metasilicate are even more preferable.

[0098] The content of the alkaline compound in the volatile organic compound reducing agent is preferably 1 to 100 parts by mass, more preferably 5 to 50 parts by mass, even more preferably 8 to 40 parts by mass, still more preferably 10 to 35 parts by mass, yet more preferably 15 to 30 parts by mass, and most preferably 16 to 25 parts by mass with respect to 100 parts by mass of the amino acid. When the content of the alkaline compound is within the above range, while maintaining the effect of reducing the volatile organic compound, damage to the object to be treated to which the volatile organic compound reducing agent is applied can be reduced, and an excellent appearance of the object to be treated can be maintained.

[0099] The volatile organic compound reducing agent may contain known additives (for example, antioxidants, ultraviolet absorbers, antistatic agents, etc.) within a range that does not impair its physical properties.

[0100] (Volatile organic compound reducing agent) The volatile organic compound reducing agent only needs to contain an amino acid. When the volatile organic compound reducing agent contains compounds other than amino acids, the volatile organic compound reducing agent can be produced by mixing the amino acid and other compounds (for example, sulfur compounds and alkaline compounds, etc.) using general means.

[0101] In producing the volatile organic compound reducing agent, after dissolving or dispersing any one or more of the amino acid and other compounds (for example, sulfur compounds and alkaline compounds, etc.) in a solvent, the amino acid and other compounds may be mixed to produce the volatile organic compound reducing agent.

[0102] In addition, as the above solvent, an aqueous solvent such as water or alcohol is preferable, and it is preferable to contain water. The solvent preferably contains 70% by mass or more of water, more preferably 80% by mass or more, still more preferably 90% by mass or more, and most preferably 100% by mass. The solvent preferably does not contain an organic solvent such as toluene, xylene, ethyl acetate, benzene, acetone, or hexane.

[0103] The content of the solvent in the reducing solution is preferably 10 to 100,000 parts by mass, more preferably 1,000 to 50,000 parts by mass, and still more preferably 2,000 to 40,000 parts by mass with respect to 100 parts by mass of the volatile organic compound reducing agent.

[0104] The volatile organic compound reducing agent may be used as a reducing solution by dissolving or dispersing it in a solvent, or it may be used without dissolving or dispersing it in a solvent. Since the volatile organic compound reducing agent can be uniformly applied to the object to be treated, it is preferably used as a reducing solution.

[0105] The pH of a 1% by mass aqueous solution of the volatile organic compound reducing agent is preferably 6 to 8, and more preferably 6.5 to 7.5. When the pH of the aqueous solution of the volatile organic compound reducing agent is within the above range, while maintaining the reducing effect of the volatile organic compound reducing agent, the damage to the object to be treated to which the volatile organic compound reducing agent is applied can be reduced, and an excellent appearance of the object to be treated can be maintained.

[0106] The usage instructions of the volatile organic compound reducer will be described. The volatile organic compound reducer can reduce or remove volatile organic compounds by contacting them. For example, the volatile organic compound reducer is supplied to and used on the object to be treated containing volatile organic compounds. As a method for supplying the volatile organic compound reducer to the object to be treated, for example, (1) a method of applying or spraying the reduction solution onto the object to be treated and then removing the solvent, (2) a method of immersing the object to be treated in the reduction solution and then removing the solvent, (3) a method of attaching the volatile organic compound reducer to the object to be treated, (4) a method of kneading the volatile organic compound reducer into the object to be treated, etc. can be mentioned. As a method of kneading the volatile organic compound reducer into the object to be treated, a method of manufacturing the object to be treated after previously mixing the volatile organic compound reducer into the raw material of the object to be treated (for example, synthetic resin, etc.) can be mentioned.

[0107] The volatile organic compound reducer can capture the volatile organic compounds contained in the object to be treated and stably reduce the amount of volatile organic compounds released from the object to be treated into the atmosphere over a long period. Therefore, according to the volatile organic compound reducer, the sick house syndrome (sick building syndrome) caused by volatile organic compounds can be suppressed.

[0108] Note that the objects to be treated include articles that release volatile organic compounds into the atmosphere. Examples of the objects to be treated include building materials such as interior and exterior finishing materials (for example, wallpapers, floor materials, roofing materials, various boards, fixtures, etc.), performance maintenance materials (sealants, heat insulation materials, sound absorption materials, waterproof materials, etc.), interior materials of transportation machines (for example, ceiling materials, surface finishing materials of seats, floor materials, etc.) such as automobiles, railways, airplanes, ships, etc., and daily necessities.

Examples

[0109] Hereinafter, the present invention will be described more specifically using examples, but the present invention is not limited by these examples.

[0110] ( Reference Examples 1 to 79, Example 80, Reference Examples 81 to 83, Examples 84 to 109, Reference Examples 110 to 172, Comparative Examples 1 to 3) Predetermined amounts of amino acids, sulfur compounds, and alkaline compounds shown in Tables 1 to 14 were mixed to prepare a volatile organic compound reducing agent. The obtained volatile organic compound reducing agent was supplied to predetermined amounts of water shown in Tables 1 to 14 and mixed to prepare a reducing solution. The unit of the amount of the compounds shown in Tables 1 to 14 is "parts by mass". The content of the volatile organic compound reducing agent in the reducing solution was 1% by mass.

[0111] Regarding the obtained reducing solution, the degree of reduction of volatile organic compounds was measured in the following manner, and the results are shown in Tables 1 to 14. The pH of the obtained reducing solution is shown in Tables 1 to 14. Reference Examples 24 to 79, Example 80, Reference Examples 81 to 83, Examples 84 to 109, and Reference Examples 110 to 144 When potassium bisulfite was used instead of sodium bisulfite as the sulfur compound, substantially the same results as those obtained when sodium bisulfite was used were obtained. Example 80 , Reference Examples 81 to 83, Example 84 ~109 and Reference Example In Examples 145 to 172, when potassium sulfite was used instead of sodium sulfite as the sulfur compound, substantially the same results as those obtained when sodium sulfite was used were obtained.

[0112] (Degree of reduction of volatile organic compounds) A cotton cloth with a plane side of 10 cm and a thickness of 3 mm was prepared. 0.5 ml of the reducing solution was impregnated into this cotton cloth to prepare a test piece.

[0113] A 3-liter sampling bag (made of vinyl alcohol-based resin) was prepared. After supplying the test piece and the volatile organic compounds (VOCs) shown in Tables 1 to 14 into this sampling bag, the air in the sampling bag was completely replaced with clean air. The concentration (initial concentration) of the volatile organic compounds in the sampling bag was adjusted to 100 volume ppm.

[0114] The sampling bag was sealed, and at an ambient temperature of 25°C, 100 milliliters of air inside the sampling bag was collected every time a predetermined time had elapsed [1H (hour), 3H (hours), 24H (hours), 48H (hours), 60H (hours), 72H (hours), 84H (hours), 96H (hours), 168H (hours)], and the amount (volume ppm) of volatile organic compounds contained in the air was measured. Based on the following formula, the reduction degree (%) of volatile organic compounds was calculated. The test was terminated when the reduction degree of volatile organic compounds reached 100%. If the reduction degree of volatile organic compounds is 98% or more by the time 7 days (168 hours) have elapsed since the start of the test, it can be said that the volatile organic compound reducing agent has an excellent effect of reducing volatile organic compounds. Reduction degree (%) of volatile organic compounds = 100×(Initial concentration of volatile organic compounds - Concentration of volatile organic compounds remaining in the sampling bag) / Initial concentration of volatile organic compounds

[0115]

Table 1

[0116]

Table 2

[0117]

Table 3

[0118]

Table 4

[0119]

Table 5

[0120]

Table 6

[0121] [Table 7]

[0122] [Table 8]

[0123] [Table 9]

[0124] [Table 10]

[0125] [Table 11]

[0126] [Table 12]

[0127] [Table 13]

[0128] [Table 14]

[0129] (Cross - reference to related applications) This application claims priority based on Japanese Patent Application No. 2019 - 169880 filed on September 18, 2019, and the disclosure of this application is incorporated herein by reference in its entirety. [Industrial Applicability]

[0130] The volatile organic compound reducer of the present invention can effectively reduce volatile organic compounds. Therefore, by treating an object to be treated such as building materials, interior materials of transportation equipment, and daily necessities with the volatile organic compound reducer, the volatile organic compounds contained in the object to be treated can be captured, and the emission of volatile organic compounds into the atmosphere can be generally prevented, and sick house syndrome and the like can be prevented in advance.

Claims

1. A reducing agent for volatile organic compounds, which contains an amino acid containing a hydrophobic amino acid and / or a hydrophilic amino acid as an active ingredient and contains an alkaline compound, wherein the hydrophobic amino acid contains at least one amino acid selected from the group consisting of alanine, glycine, valine, isoleucine, leucine, phenylalanine, tyrosine, tryptophan, methionine, and cysteine, or a salt of the amino acid, the hydrophilic amino acid contains at least one amino acid selected from the group consisting of lysine, arginine, histidine, aspartic acid, glutamic acid, serine, threonine, asparagine, and glutamine, or a salt of the amino acid, the alkaline compound contains at least one of calcium hydroxide and sodium metasilicate, and a reducing agent for volatile organic compounds, characterized by containing salts of the alanine, the glycine, and the cysteine.

2. A reducing agent for volatile organic compounds, which contains an amino acid containing a hydrophobic amino acid and / or a hydrophilic amino acid as an active ingredient and contains an alkaline compound, wherein the hydrophobic amino acid contains at least one amino acid selected from the group consisting of alanine, glycine, valine, isoleucine, leucine, phenylalanine, tyrosine, tryptophan, methionine, and cysteine, or a salt of the amino acid, the hydrophilic amino acid contains at least one amino acid selected from the group consisting of lysine, arginine, histidine, aspartic acid, glutamic acid, serine, threonine, asparagine, and glutamine, or a salt of the amino acid, the alkaline compound contains at least one of calcium hydroxide and sodium metasilicate, and a reducing agent for volatile organic compounds, characterized by containing a sulfur compound.

3. The reducing agent for volatile organic compounds according to Claim 2, characterized by containing at least one sulfur compound selected from the group consisting of sulfites, bisulfites, and pyrosulfites.

4. The reducing agent for volatile organic compounds according to Claim 2 or Claim 3, characterized by containing 10 to 3000 parts by mass of a sulfur compound with respect to 100 parts by mass of the amino acid.

5. A method for reducing a volatile organic compound, comprising supplying a reducing agent for a volatile organic compound according to any one of claims 1 to 4 to a body to be treated containing the volatile organic compound, and reducing the volatile organic compound contained in the body to be treated.

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