Method for producing flavor composition and caramel-like coloring agent

Abstract

The present invention aims to induce the Maillard reaction under novel conditions and utilize the resulting substance as a food flavor composition and caramel-like coloring agent. [Solution] 1. A method for producing a flavor composition and a caramel-like coloring agent, characterized by adjusting a solution containing an organic substance having a primary amino group, or a food material containing the organic substance, and sugars to a pH of 0 to 2.0, heating it, and inducing a Maillard reaction. 2. A method for producing the flavor composition and caramel-like coloring agent according to claim 1, wherein the heating temperature is 70°C to 130°C and the heating time is 10 minutes to 5 hours.

Description

Technical Field

[0001] The present invention relates to a flavor composition and a method for producing a caramel-like coloring agent, which are characterized by inducing the Maillard reaction under strongly acidic conditions. More specifically, it relates to a method for producing a flavor composition and a caramel-like coloring agent, which comprises adjusting a solution containing a substance having an amino group and a saccharide to pH 0 to pH 2.0, and then heating it to 70°C to 130°C to induce the Maillard reaction. By adding the flavor composition or the coloring agent of the present invention, a favorable flavor, roasted color, or a deep caramel-like brown color can be imparted to foods.

Background Art

[0002] The Maillard reaction is a reaction in which a reducing sugar such as glucose or fructose and an amino compound are heated to produce a brown substance (melanoidin), and it is a kind of amino-carbonyl reaction. It is regarded as a very important reaction involved in the coloring of products, the generation of aroma components, and the generation of antioxidant components during food processing and storage. The aroma components produced by the Maillard reaction vary depending on the types of amino compounds and sugars, reaction conditions, etc., and various aromas such as burnt odor, caramel odor, nut-like odor, bread-like odor, chocolate odor, and violet flower-like odor are generated (see Non-Patent Document 1). The melanoidin (product of the Maillard reaction) in foods has been most thoroughly studied for the pigment in soy sauce, and the absorbance in the visible region of 400 nm to 550 nm is used as an index (see Non-Patent Document 2).

[0003] The Maillard reaction is considered to proceed as the reaction substrate concentration and temperature increase, and as the pH becomes more alkaline (see Non-Patent Document 3). In particular, the aroma of roasted meat is mainly attributed to the Maillard reaction between cysteine, which is a sulfur-containing amino acid, and sugar. A technology for imparting a roasted meat flavor based on mixing cysteine or peptides containing cysteine and a reducing sugar and heating them to cause the Maillard reaction has been developed.

[0004] For example, a flavor additive produced by the Maillard reaction of glutathione and xylose with cysteine ​​or cysteine-containing peptides (see Patent Document 1), a method for producing canned goods and the like in which L-ascorbic acid or erythorbic acid is added to cystine, cysteine, or glutathione and monosaccharides to enhance meat flavor (see Patent Documents 2 and 3), and a method for producing a seasoning having a roast meat flavor by adding sugars and amino acids to a yeast extract containing a certain amount of sulfur-containing compounds such as glutathione and heating it (see Patent Document 4) have been disclosed. More recently, a method for producing a seasoning having a roast meat-like flavor has been disclosed by mixing sulfur-containing amino acids such as cysteine, cystine, and methionine, or sulfur-containing peptides such as glutathione and γ-glutamylcysteine ​​with yeast extract, sugars, and nucleic acid-related substances to make an aqueous solution and heating it under two different pH conditions: pH 3.5 to 5.5 and pH 6.0 to 8.0 (see Patent Document 5).

[0005] Research on Maillard reaction products with similar meat flavors is also being actively conducted overseas, and many papers are based on the use of cysteine ​​as the amino acid and xylose as the sugar (see, for example, Non-Patent Documents 4 to 6).

[0006] In 2022, the standards for food additives were revised, making L-cysteine ​​hydrochloride available for use as a seasoning (see Non-Patent Document 7). The effectiveness of L-cysteine ​​hydrochloride is said to be that when added to chicken soup at a concentration of 0.005% at the time of consumption, it enhances the flavor by increasing the roasted and fatty taste through the Maillard reaction (see Non-Patent Document 8).

[0007] It is well known that sucrose hydrolyzes into glucose and fructose when heated under strong acid conditions (see Non-Patent Document 9), but highly polymerized sugars such as starch and inulin are similarly hydrolyzed when heated under strong acid conditions (see Non-Patent Documents 10 and 11). When starch decomposes, it becomes glucose, and when inulin decomposes it becomes a mixture of glucose and fructose (with fructose being overwhelmingly more abundant).

[0008] The Maillard reaction is a well-known reaction that has been around for a long time, and it has been believed to proceed easily in neutral to alkaline conditions. In the prior art and overseas research mentioned above, the pH before heating in reaction tests was 3.0 or higher, and it was completely unknown that the Maillard reaction proceeds easily below 3.0, especially in the extremely low pH range of pH 0 to pH 2.0.

[0009] On the other hand, caramel is made from sugars and glucose and has been used since ancient times as a natural brown pigment. The reaction that produces caramel is called caramelization, and it is basically a polymerization reaction that occurs by roasting sugars. Methods of production include the acid roasting method, in which acid is added to sugars to adjust the pH to 3-4 and roast at around 160°C; the alkali roasting method, in which a small amount of caustic soda or sodium carbonate is added to a reducing sugar solution and roasted; and the catalytic reaction method, which uses glucose, starch saccharification solution, or crystalline glucose waste molasses as raw materials and uses ammonia or ammonium salt as a catalyst (see Non-Patent Literature 12). Currently, products made without a catalyst are classified as caramel I, those made with sulfite compounds as a catalyst as caramel II, those made with ammonium compounds as a catalyst as caramel III, and those made with both compounds as caramel IV (see Non-Patent Literature 13).

[0010] Examples of manufacturing technologies being considered include a method of continuously extruding monosaccharides, disaccharides, starch, and dextrin under heating conditions of 150-300°C after adjusting the pH to 2-4 and the moisture content to 5-25% by weight (see Patent Document 6), a method of continuously producing ammonia caramel (see Patent Document 7), and a method for producing antioxidant caramel characterized by adding a basic compound to monosaccharides and heat-treating it at 120-150°C for 1-10 hours (see Patent Document 8). Furthermore, methods for producing caramel-like substances have been disclosed, such as a method of obtaining a precipitate by adding an organic solvent to a yeast fermentation liquid (see Patent Document 9), and a method of heating a mixture of sugars and amino acids in a weight ratio of 1:0.1 to 1:1.2 at 40-90°C, then adjusting the pH to 6-9 to perform a Maillard reaction (see Patent Document 10).

[0011] Caramel pigments often use caramel III and caramel IV with high color intensity, but these caramels are said to contain 4-methylimidazole (4-MEI), a carcinogenic substance. This substance is produced by using an ammonium compound as a catalyst, but a caramel pigment with high color intensity and no 4-MEI is desired (see Non-Patent Document 14).

Prior Art Documents

Patent Documents

[0012]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Patent Document 10

Non-Patent Documents

[0013]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Non-Patent Document 5

Non-Patent Document 6

Non-Patent Document 7

Non-Patent Document 8

Non-Patent Document 9

Non-Patent Document 10

Non-Patent Document 11

Non-Patent Document 12

Non-Patent Document 13

Non-Patent Document 14

Summary of the Invention

Problems to be Solved by the Invention

[0014] The problem to be solved by the present invention is to provide a flavor composition that imparts a favorable flavor or a caramel-like coloring agent that imparts a favorable color and taste when added to food or further heat-processed after addition by inducing the Maillard reaction in an extremely low pH range of pH 0 to pH 2.0.

Means for Solving the Problems

[0015] As a result of intensive research to solve the above problems, the inventor measured the pH after dissolving L-cysteine hydrochloride (the commercially available product is L-cysteine hydrochloride monohydrate) at 1% by weight in isomerized sugar with a Brix value of 73.8%, and confirmed that it was very low at 1.01. When this solution was exposed to boiling water for 1 hour, it was found that browning, which was conventionally considered difficult to occur, occurred rapidly, and a roast meat-like flavor composition was formed. Based on this finding, an aqueous solution of 70% by weight of reducing sugar (glucose, fructose, xylose) containing 1% by weight of L-cysteine hydrochloride monohydrate was finely adjusted in the pH range of pH 0 to pH 9 and heated in boiling water, and it was found that browning progressed rapidly within the pH range of pH 0 to pH 2.0. Particularly in the case of fructose and xylose, it was found that a more significant reaction occurred within the pH range of pH 0 to pH 2 than in the pH range of pH 7 to pH 9 where the Maillard reaction is likely to occur, and a roast meat-like flavor composition with a stronger flavor was generated.

[0016] Next, the same process was followed for standard amino acids other than cysteine ​​(leucine, methionine, tryptophan, threonine, serine, proline, valine, alanine, tyrosine, histidine, glutamine, glycine, aspartic acid, glutamic acid, phenylalanine, lysine, isoleucine, arginine, and asparagine). When 1% by weight of each amino acid was added to a 70% by weight fructose aqueous solution, the pH was adjusted to 1.0-2.0 with hydrochloric acid, and the mixture was heated in boiling water, browning was observed for most amino acids. Furthermore, the characteristic aroma of each amino acid's Maillard reaction product (see Non-Patent Document 1) was detected, confirming that a reaction similar to the Maillard reaction carried out in neutral to alkaline conditions was occurring.

[0017] Furthermore, when an aqueous solution containing 1% by weight of thiamine (vitamin B1), a water-soluble vitamin containing amino groups and sulfur, and 70% by weight of fructose was prepared to a pH range of 1.0 to 2.0 and heated in boiling water, a significant browning and the formation of a strong roasted meat-like flavor composition were observed.

[0018] Furthermore, in Maillard reaction tests of 20 standard amino acids, the browning of cysteine ​​and tryptophan was particularly pronounced. By examining the amount of cysteine ​​and tryptophan added, as well as the heating temperature and time, it was discovered that a composition with a color value comparable to caramel could be produced, thus completing the present invention. The method for producing the caramel-like colorant of the present invention is similar to that of Patent Document 10 in that it uses amino acids and sugars as raw materials, but the range of pH adjustment before the Maillard reaction is fundamentally different. In the present invention, adjusting the pH to the range of 0 to 2.0 is an essential condition.

[0019] Therefore, the present invention is constructed as follows. [Claim 1] Organic substances having primary amino groups, or food materials containing said organic substances A method for producing a flavor composition and a caramel-like coloring agent, characterized by adjusting a solution containing sugars to pH 0 to 2.0 and heating it to induce a Maillard reaction. [Claim 2] A method for producing a flavor composition and caramel-like coloring agent according to claim 1, wherein the heating temperature is 70°C to 130°C and the heating time is 10 minutes to 5 hours. [Claim 3] A method for producing a flavor composition and caramel-like coloring agent according to claim 1 or 2, characterized by arbitrarily mixing an organic substance having an amino group in an amount from 0.1% to 50% by weight and sugars in an amount from 0.1% to 85% by weight to form a solution. [Claim 4] A method for producing a flavor composition according to any one of claims 1 to 3, characterized in that the organic substance having an amino group contains sulfur. [Claim 5] A method for producing a flavor composition according to any one of claims 1 to 4, wherein the organic substance having an amino group and containing sulfur is selected from the group consisting of cysteine, thiamine, cystine, homocysteine, methionine, taurine, alliin, S-allylcysteine, glutathione, cystathionine, and lentinic acid. [Claim 6] A method for producing a caramel-like colorant according to any one of claims 1 to 3, characterized in that the organic substance having an amino group contains either or both cysteine ​​and tryptophan. [Claim 7] A method for producing a flavor composition and caramel-like coloring agent according to claim 1, wherein the food material of claim 1 comprises one or more selected from the group consisting of yeast, live meat, fish meat, legumes, grains, vegetables, fruits, and their dried products and extracts. [Claim 8] A method for producing a flavor composition and caramel-like coloring agent according to any one of claims 1 to 7, wherein the sugar is one or more selected from the group consisting of ribose, xylose, arabinose, glucose, mannose, fructose, maltose, lactose, sucrose, starch, and inulin. [Claim 9] A method for producing a flavor composition and caramel-like coloring agent according to any one of claims 1 to 8, characterized in that the sugars particularly include fructose. [Claim 10] A flavor composition and a caramel-like coloring agent obtained by applying the manufacturing method described in any one of claims 1 to 9, and a food product to which these are added. [Effects of the Invention]

[0020] According to the present invention, by adjusting the pH of an aqueous solution containing substances having amino groups, such as amino acids, peptides, and thiamine, to a range of 0 to 2.0 and heating it, a Maillard reaction can be efficiently induced, and a composition that can impart a desirable flavor and dark brown color with only a small amount of addition can be obtained. In particular, by reacting substances having amino groups and containing sulfur, such as cysteine ​​and thiamine, with sugars containing fructose in a pH range of 0 to 2.0, a desirable roasted meat-like flavor composition can be obtained. Furthermore, by reacting cysteine ​​and tryptophan with sugars containing fructose in a pH range of 0 to 2.0, a caramel-like coloring agent that can impart a dark brown color can be obtained. [Brief explanation of the drawing]

[0021] [Figure 1] This figure shows the browning state induced by the Maillard reaction in an aqueous solution containing 1% by weight of each of the following 20 standard amino acids: leucine (Leu), methionine (Met), tryptophan (Trp), threonine (Thr), and serine (Ser), along with 70% by weight of fructose, adjusted to a pH range of 1.0 to 2.0. [Figure 2] This figure shows the browning state induced by the Maillard reaction in an aqueous solution containing 1% by weight of each of the following 20 standard amino acids: proline (Pro), valine (Val), alanine (Ala), tyrosine (Tyr), and histidine (His), along with 70% by weight of fructose, adjusted to a pH range of 1.0 to 2.0. [Figure 3]This figure shows the browning state induced by the Maillard reaction in an aqueous solution containing 1% by weight of each of the following 20 standard amino acids: cysteine ​​(Cys), glutamine (Gln), glycine (Gly), aspartic acid (Asp), and glutamic acid (Glu), along with 70% by weight of fructose, adjusted to a pH range of 1.0 to 2.0. [Figure 4] This figure shows the browning state induced by the Maillard reaction in an aqueous solution containing 1% by weight of each of the following 20 standard amino acids: phenylalanine (Phe), lysine (Lys), isoleucine (Ile), arginine (Arg), and asparagine (Asn), along with 70% by weight of fructose, adjusted to a pH range of 1.0 to 2.0. [Figure 5] This figure shows the browning state induced by the Maillard reaction in an aqueous solution of 20% by weight of yeast extract and 70% by weight of fructose, adjusted to pH 1.75. [Figure 6] This graph shows the relative absorbance of each solution, with the absorbance of the pH 1.2 solution set to 1.0 [Figure 7] This graph shows the relative absorbance of each solution after inducing the Maillard reaction by preparing 11 different aqueous solutions of a 1% L-cysteine ​​hydrochloride and 69% fructose mixture at pH levels of 0.4, 0.7, 1.2, 1.9, 3.1, 4.0, 4.9, 6.0, 7.2, 8.0, and 9.3. The absorbance of the pH 1.2 aqueous solution is set to 1. [Figure 8] This graph shows the relative absorbance of each solution, with the absorbance of the pH 1.0 solution set to 1.0. Eleven different aqueous solutions of 1% L-cysteine ​​hydrochloride and 69% xylose by weight were prepared at pH 0.2, 0.4, 1.0, 2.2, 3.1, 4.0, 5.0, 6.0, 7.2, 8.1, and 9.1 to induce the Maillard reaction. [Figure 9]This figure shows the browning state after the Maillard reaction of three aqueous solutions: a mixed aqueous solution of 1% L-cysteine ​​hydrochloride and 69% fructose (pH 1.2), a mixed aqueous solution of 1% L-cysteine ​​hydrochloride and 69% xylose (pH 0.2), and a mixed aqueous solution of 1% L-cysteine ​​hydrochloride and 69% glucose (pH 9.2). [Figure 10] This figure compares the browning state after the Maillard reaction of a mixed aqueous solution of 1% L-cysteine ​​hydrochloride and 69% fructose (pH 1.2) and a mixed aqueous solution of 1% L-cysteine ​​hydrochloride and 69% inulin (pH 1.2). [Figure 11] This figure shows the browning state of compositions 1 to 4 in Example 2. [Figure 12] This graph shows the relative absorbance of each solution, with the absorbance of the pH 1.0 solution set to 1.0. Eleven different aqueous solutions of 1% L-tryptophan and 69% fructose by weight were prepared at pH 0.4, 0.6, 1.0, 2.1, 3.0, 4.0, 5.0, 6.1, 7.0, 8.0, and 9.0 to induce the Maillard reaction. [Modes for carrying out the invention]

[0022] As raw materials for the Maillard reaction product according to the present invention, all substances known to undergo the Maillard reaction can be used, but in particular, sulfur-containing amino acids, peptides and proteins containing sulfur-containing amino acids, thiamine (a water-soluble vitamin having an amino group and sulfur), cells, tissues, extracts, and decomposition products of plants, animals, and microorganisms (fungi and bacteria, etc.), and reducing sugars (ribose, xylose, arabinose, glucose, mannose, fructose, sucrose, maltose, lactose, etc.), as well as sucrose, starch, and inulin. As shown in Non-Patent Documents 9 to 11, sucrose, starch, and inulin decompose into glucose and fructose when heated under strong acid, and therefore can be used as raw materials for the present invention.

[0023] The conventional Maillard reaction is induced by heating a solution of one or more substances containing amino groups and one or more reducing sugars, adjusted to a neutral to alkaline pH. However, in this invention, the mixed solution is adjusted to a strongly acidic pH range of 0 to 2.0 and heated to induce the reaction. The reaction proceeds more rapidly with higher heating temperatures and longer heating times, but a good Maillard reaction product can be obtained by heating at 70°C to 130°C for 10 minutes to 5 hours.

[0024] To produce a roast beef-like flavor composition, an aqueous solution of L-cysteine ​​or L-cysteine-containing peptides (e.g., glutathione) and reducing sugars, particularly fructose, is heated in boiling water with the pH adjusted to a range of 0 to 2.0. L-cysteine ​​hydrochloride, in particular, has a very low pH of 1 to 1.2 in a 1% aqueous solution, making pH adjustment very easy. For example, a solution of 1% by weight of L-cysteine ​​hydrochloride dissolved in a 70% by weight fructose aqueous solution has a pH of 1.01. Therefore, the desired flavor composition can be produced simply by heating this solution in boiling water for 0.5 to 5 hours, preferably 0.5 to 2.0 hours. If an autoclave or retort sterilizer is available, heating at 110°C for 10 to 30 minutes will produce a sufficiently desirable flavor composition. By adding other amino acids or food ingredients rich in amino acids, peptides, proteins, etc., such as yeast extract, in addition to L-cysteine ​​hydrochloride, a more complex and natural roast meat-like flavor composition can be produced. If the pH value shifts to the neutral side beyond the 0-2.0 range after adding amino acids other than L-cysteine ​​hydrochloride or food ingredients, the pH value can be adjusted back to the 0-2.0 range using inorganic acids such as hydrochloric acid or phosphoric acid, or relatively strong organic acids such as citric acid or malic acid.

[0025] Similar to L-cysteine, thiamine, when added to an aqueous solution, particularly one containing fructose, and adjusted to a pH range of 0 to 2.0, and then heated in boiling water, can produce a composition with a roast meat-like flavor. Compositions using L-cysteine ​​as a raw material have a roast beef-like flavor, while compositions using thiamine as a raw material have a char siu (roasted pork)-like flavor.

[0026] Among sulfur-containing amino acids and peptides other than cysteine, cystine and glutathione can be used to create flavor compositions similar to those of cysteine. Methionine and S-allyl cysteine, on the other hand, have unique characteristics; the former produces a flavor composition reminiscent of boiled potatoes, while the latter produces one reminiscent of roasted leeks.

[0027] Any type of reducing sugar, sucrose, starch, or inulin can be used, but glucose, fructose, xylose, and inulin are particularly good. Of these four, fructose and inulin are the most likely to induce the Maillard reaction within the pH range of 0 to 2.0, followed by xylose. However, compositions made with xylose have a distinctive unpleasant taste, so it is preferable to use fructose, inulin, or a mixture of fructose and glucose (e.g., isomerized sugar).

[0028] Garlic bulbs contain approximately 1% alliin and arginine, and approximately 9-16% inulin. When garlic extract containing high concentrations of alliin and arginine is heated in boiling water with the pH adjusted to a range of 0-2.0, a flavor composition with a strong roasted garlic flavor is produced.

[0029] When an aqueous solution containing standard amino acids and fructose is adjusted to a pH range of 0 to 2.0 to induce the Maillard reaction, cysteine ​​and tryptophan brown particularly strongly. By examining the proportions of cysteine ​​and tryptophan, as well as the heating temperature and time, it is possible to produce caramel-like colorants with a color value comparable to commercially available caramel colorants.

[0030] The present invention will be described in more detail below with reference to examples, but the technical scope of the present invention is not limited to these examples. Experimental Example 1

[0031] Twenty standard amino acids used as food additives were prepared. 0.1 g of each amino acid, 7.0 g of fructose, and 2.5 g of pure water were placed in 50 ml centrifuge tubes and immersed in a water bath set to 60°C. After the amino acids and fructose had dissolved, the tubes were removed and cooled with water. The pH was then adjusted to a range of 1.0 to 2.0 using an aqueous solution of special grade hydrochloric acid (35% to 37%) diluted with pure water as appropriate. After adjustment, pure water was added to each solution to bring the total to 10.0 g, and the tubes were immersed in boiling water and kept warm for 1 hour to induce the Maillard reaction. The browning of each amino acid solution after the reaction is shown in Figures 1 to 4.

[0032] Although the degree varied, browning was observed in each amino acid solution, revealing that standard amino acids undergo the Maillard reaction in the pH range of 0 to 2.0. Furthermore, the degree of browning was significantly higher for cysteine ​​and tryptophan. Experimental Example 2

[0033] 2.0 g of yeast extract (Ohly KAV, Higuchi Shokai Co., Ltd.), 14.0 g of fructose, and 4.0 g of 5N hydrochloric acid aqueous solution were placed in a 50 ml centrifuge tube and mixed. The mixture was then immersed in a water bath set to 60°C to dissolve the mixture. The pH after dissolution was 1.75, and it was confirmed that it was within the range of 0 to 2.0. This solution was divided into two equal parts, each placed in a 50 ml centrifuge tube. One tube was immersed in boiling water and kept warm for 1 hour to induce the Maillard reaction. Figure 5 shows the browning after heating compared to the unheated sample.

[0034] Even materials like yeast extract underwent a significant Maillard reaction under strongly acidic conditions below pH 2.0, demonstrating that the Maillard reaction, previously thought to occur more easily in neutral to alkaline conditions, can also readily occur under strongly acidic conditions. (Experimental Example 3)

[0035] Eleven 50 ml centrifuge tubes were prepared, each containing 0.1 g of L-cysteine ​​hydrochloride and 6.9 g of glucose. Three of these tubes were removed. 3 g of 1 N hydrochloric acid solution was added to one tube, 3.0 g of 0.5 N hydrochloric acid solution to another, and 3.0 g of pure water to the remaining tube. These were then immersed in a water bath set to 60°C to dissolve the compounds. 2.5 g of pure water was added to the other eight tubes, and they were then immersed in a water bath set to 60°C to dissolve the compounds. After dissolution, these centrifuge tubes were cooled with water to bring the solution temperature down to room temperature, and the pH of the first three tubes was measured. For the other eight tubes, each was removed individually, and 1 N sodium hydroxide was added little by little while measuring the pH, adjusting the pH to approximately pH 2, pH 3, pH 4, pH 5, pH 6, pH 7, pH 8, and pH 9, respectively. After adjustment, pure water was added until the total solution weight was 10.0 g. Similarly, eleven tubes each of solutions containing L-cysteine ​​hydrochloride and fructose, and L-cysteine ​​hydrochloride and xylose were prepared. All of these centrifuge tubes were immersed in boiling water and kept warm for one hour to induce the Maillard reaction. After the reaction, all centrifuge tubes were cooled with water to lower the liquid temperature to approximately room temperature, and the absorbance at a wavelength of 450 nm, which is an indicator of the amount of melanoidin produced, was measured using a spectrophotometer (UV-1700, Shimadzu Corporation) (see Non-Patent Literature 2). The relative absorbance of each solution, with the absorbance of the solutions with pH 1 to 1.2 set to 1, is shown in Figures 6 to 8.

[0036] For all types of sugars, a tendency was observed for absorbance to be higher in solutions with lower pH levels within the pH 0 to pH 2.2 range, and higher in solutions with higher pH levels within the pH 7.0 to pH 9.3 range. Glucose showed the highest relative absorbance in a solution at pH 9.2, while fructose showed the highest relative absorbance in a solution at pH 0.4, and xylose showed the highest relative absorbance in a solution at pH 0.2. Furthermore, the absorbance of the fructose solution at pH 0.4 (68.72 Abs, calculated by multiplying the measured value by the dilution factor) was approximately 24.4 times higher than that of the glucose solution at pH 9.2 (2.82 Abs), and approximately 6.2 times higher than that of the xylose solution at pH 0.2 (11.06 Abs, calculated by multiplying the measured value by the dilution factor). Even the pH 1.2 solution exceeded the absorbance of the glucose solution at pH 9.2 and the xylose solution at pH 0.2 (see Figure 9), clearly indicating that fructose solutions are particularly prone to the Maillard reaction within the pH range of 0 to 2.0. Experimental Example 4

[0037] Two 50 ml centrifuge tubes were prepared, one containing 0.1 g of L-cysteine ​​hydrochloride and 6.9 g of fructose, and the other containing 0.1 g of L-cysteine ​​hydrochloride and 6.9 g of inulin (Fuji FF HS, Fuji Nippon Sugar Refining Co., Ltd.). 3 g of pure water was added to each tube, and they were immersed in a water bath set to 60°C to dissolve the substances. After dissolution, these centrifuge tubes were immersed in tap water to cool to room temperature, and the pH was measured to confirm that both were approximately 1.2. These centrifuge tubes were immersed in boiling water for 1 hour to induce the Maillard reaction, and the browning state was compared. The results are shown in Figure 10.

[0038] As shown in Figure 10, the degree of browning when the sugar was replaced with inulin was about the same as when the sugar was fructose, and we confirmed that the resulting aroma was also almost identical. [Examples]

[0039] 99 g of a 70% weight fructose aqueous solution and 1 g of L-cysteine ​​hydrochloride (CJ Japan Co., Ltd.) were placed in a 100 ml glass bottle, the lid was closed, and the bottle was immersed in a water bath set to 60°C to completely dissolve the L-cysteine ​​hydrochloride. After cooling the solution with water to room temperature, the pH was measured and confirmed to be within the range of 1.0 to 1.2. After confirmation, the lid was tightly closed and the bottle was immersed in boiling water for 1 hour to induce the Maillard reaction, thereby producing a roast beef-like flavor composition (Composition A).

[0040] 99g of a 70% by weight fructose aqueous solution in 1N hydrochloric acid (70g of fructose dissolved in 30g of 1N hydrochloric acid) and 1g of thiamine hydrochloride (Taisho Technos Co., Ltd.) were placed in a 100ml glass bottle, the lid was closed, and the bottle was immersed in a water bath set to 60°C to completely dissolve the thiamine hydrochloride. After cooling the solution with water to room temperature, the pH was measured and confirmed to be within the range of 1.0 to 1.2. After confirmation, the lid was tightly closed and the bottle was immersed in boiling water for 1 hour to induce the Maillard reaction, thereby producing a roast pork-like flavor composition (Composition B).

[0041] 2.5g of Chinese soup base (Somi Shantan powder type, Somi Foods Co., Ltd.) was mixed with 1.5g of a prepared roast meat-like flavor composition, and hot water was added to make a total volume of 150g. The soup to which composition A was added changed significantly from its original chicken flavor to a flavor closer to beef, and the richness of the flavor also increased greatly. The soup to which composition B was added changed from a chicken flavor to a flavor similar to char siu (Chinese BBQ pork), and emitted a stronger aroma than composition A. Although these compositions have a very low pH, no sourness was detected in the soup to which they were added. [Examples]

[0042] 99 g of 70% fructose aqueous solution and 1 g of L-cysteine ​​hydrochloride (CJ Japan Co., Ltd.) were placed in a 100 ml glass bottle, the lid was closed, and the bottle was immersed in a water bath set to 60°C to completely dissolve the L-cysteine ​​hydrochloride. After cooling the solution with water to room temperature, the pH was measured and confirmed to be within the range of 1.0 to 1.2. After confirmation, the lid was tightly closed and the bottle was immersed in a water bath set to 70°C for 1 hour to induce the Maillard reaction. After cooling with water, 10.0 g was collected in a 50 ml centrifuge tube and designated as Composition 1. The glass bottle containing the remaining solution was immersed in a water bath set to 80°C for 1 hour to further induce the Maillard reaction. After cooling with water, 10.0 g was collected in a 50 ml centrifuge tube and designated as Composition 2. Similarly, the glass bottle containing the remaining solution was immersed in a water bath set to 90°C for 1 hour, and after cooling with water, 10.0 g was collected and designated as Composition 3. Furthermore, the glass bottle containing the remaining solution was immersed in boiling water for 1 hour, then cooled with water and collected as composition 4. The browning state of compositions 1 to 4 is shown in Figure 11.

[0043] 2.5g of Chinese soup base (Somi Shantan powder type, Somi Foods Co., Ltd.) was mixed with hot water to make a total volume of 150g. This soup was divided into five 30g containers. One container was unadded, and the other four were each mixed with 0.3g of Composition 1 to Composition 4. The soup with Composition 1 had an enhanced chicken flavor, Composition 2 had a pork flavor, and Compositions 3 and 4 had a beef flavor. In other words, by controlling the heating temperature, flavor compositions that impart the flavors of roast chicken, roast pork, and roast beef could be produced. However, the roast beef flavor was the strongest, and the roast pork flavor was overwhelmingly stronger in Composition B prepared in Example 1. [Examples]

[0044] 100g of dried soy protein was rehydrated by soaking it in 400ml of water. Using this rehydrated soy protein, hamburgers were made without the flavor compositions (composition A and composition B) prepared in Example 1 (control) and with the flavor compositions (hamburger A and hamburger B). The flavors were then compared by frying them in a pan. Table 1 shows the recipes for the hamburgers.

[0045] [Table 1]

[0046] The control hamburger had a strong soy smell, and although it contained pork equivalent to 20% of the soy protein weight, there was almost no meat flavor. In contrast, hamburger A still had a soy flavor, but a strong roast beef flavor was noticeable. Similarly, hamburger B also still had a soy flavor, but a strong roast pork flavor was noticeable. [Examples]

[0047] 98g of a 1N hydrochloric acid aqueous solution of 70% by weight fructose, 1g of L-cysteine ​​hydrochloride (CJ Japan Co., Ltd.), and 1g of L-methionine (Kyowa Hakko Bio Co., Ltd.) were placed in a 100ml glass bottle, the lid was closed, and the bottle was immersed in a water bath set to 60°C to completely dissolve the L-cysteine ​​hydrochloride and L-methionine. After cooling the solution to room temperature, the pH was measured and confirmed to be within the range of 1.0 to 1.2. After confirmation, the lid was tightly closed and the bottle was immersed in boiling water for 1 hour to induce the Maillard reaction and produce a beef croquette-like flavor composition. When 1.5g of this composition was added to the control recipe for soy protein hamburger (Table 1) and cooked in a frying pan, a strong flavor resembling a croquette containing ground beef was detected along with a soy odor. [Examples]

[0048] 98g of a 1N hydrochloric acid aqueous solution of 70% by weight fructose, 1g of thiamine hydrochloride (Taisho Technos Co., Ltd.), and 1g of S-allyl cysteine ​​(Tokyo Chemical Industries, Ltd.) were placed in a 100ml glass bottle, the lid was closed, and the bottle was immersed in a water bath set to 60°C to completely dissolve the thiamine hydrochloride and S-allyl cysteine. After cooling the solution to room temperature, the pH was measured and confirmed to be within the range of 1.0 to 1.2. After confirmation, the lid was tightly closed and the bottle was immersed in boiling water for 1 hour to induce the Maillard reaction, thereby producing a pork and green onion-like flavor composition. When 1.5g of this composition was added to the control recipe for soy protein hamburger (Table 1) and cooked in a frying pan, a strong soy odor was detected along with a flavor similar to that of pork and green onions cooked together. [Examples]

[0049] A garlic extract with a Brix of 40% was prepared as shown in Production Example 2 of Japanese Patent Publication No. 2020-129993, freeze-dried, and then pulverized to form a powder. 10 g of this powder and 30 g of 2N hydrochloric acid aqueous solution were placed in a 50 ml centrifuge tube and dissolved by immersion in a water bath set at 60°C. After cooling to room temperature by immersion in tap water, the pH of the solution was measured and confirmed to be within the range of 1.0 to 2.0. After confirmation, the solution was immersed in boiling water for 2 hours to induce the Maillard reaction and produce a roasted garlic-like flavor composition (Composition C).

[0050] Flavor compositions were prepared by mixing composition A and composition C in a weight ratio of 9:1 (composition D) and by mixing composition B and composition C in a weight ratio of 9:1 (composition E). 1.5g of each composition was added to 2.5g of the Chinese soup base used in Example 1, and hot water was poured in to make a total volume of 150g. The soup with composition D had a roast beef flavor, and the soup with composition E had a roast pork flavor, both with a hint of roasted garlic, resulting in very desirable Chinese soup flavors. Experimental Example 5

[0051] Eleven 50 ml centrifuge tubes containing 0.1 g of L-tryptophan and 6.9 g of glucose were prepared. 2.5 g of pure water was added to each tube, and the tubes were immersed in a water bath set to 60°C to dissolve the L-tryptophan. After dissolution, these centrifuge tubes were cooled with water to bring the solution temperature down to room temperature. Then, the pH values ​​of each tube were adjusted to approximately pH 0.4, pH 0.6, pH 1, pH 2, pH 3, pH 4, pH 5, pH 6, pH 7, pH 8, and pH 9 using appropriately diluted hydrochloric acid and sodium hydroxide solutions. After adjustment, pure water was added to bring the solution weight to 10.0 g. All centrifuge tubes were then immersed in boiling water and kept warm for 1 hour to induce the Maillard reaction. After the reaction, all centrifuge tubes were cooled with water to bring the solution temperature down to room temperature, and the absorbance at a wavelength of 450 nm was measured using a spectrophotometer (UV-1700, Shimadzu Corporation). Figure 12 shows the relative absorbance of each solution, with the absorbance of a pH 1.0 solution set to 1.

[0052] As shown in Figure 12, the Maillard reaction between tryptophan and fructose is significantly induced when the pH drops below 1. While the absorbance of the reactants at pH 2-9 is 0.46-1.25 Abs, the absorbance of the reactant at pH 1.0 is 63.25 Abs (calculated by multiplying the measured value by the dilution factor), the absorbance at pH 0.6 is 150.50 Abs (calculated by multiplying the measured value by the dilution factor), and the absorbance at pH 0.4 is 291.40 Abs (calculated by multiplying the measured value by the dilution factor), showing a rapid increase when the pH drops below 1.0. Compared to the absorbance of the Maillard reaction product between cysteine ​​and fructose at pH 0.4, which was 68.72 Abs (calculated by multiplying the measured value by the dilution factor), the absorbance of the Maillard reaction product between tryptophan and fructose induced at pH 0.4 was more than four times higher. [Examples]

[0053] 5% by weight of L-cysteine hydrochloride, 70% by weight of fructose, and 25% by weight of pure water were mixed and immersed in a water bath set at 60°C to dissolve (pH 1.16). This solution was dispensed to four testers at 10.0 g each. Similarly, 2% by weight of L-tryptophan, 70% by weight of fructose, 6% by weight of 10N hydrochloric acid aqueous solution, and 22% by weight of pure water were mixed and immersed in a water bath set at 60°C to dissolve (pH 1.40). This solution was dispensed to four testers at 10.0 g each. Two testers of L-cysteine and two testers of L-tryptophan were immersed in boiling water, taken out one by one after being kept warm for 3 hours, and cooled with tap water. The remaining two were taken out after being kept warm for 5 hours and cooled with tap water. The generated Maillard reaction products were designated as Specimen 1 for the 3-hour reaction product of the L-cysteine tester, Specimen 2 for the 5-hour reaction product, Specimen 3 for the 3-hour reaction product of the L-tryptophan tester, and Specimen 4 for the 5-hour reaction product.

[0054] One tester each of L-cysteine and L-tryptophan was placed in an autoclave and heated at 110°C for 10 minutes. The remaining one each was heated at 110°C for 30 minutes. The generated Maillard reaction products were designated as Specimen 5 for the 10-minute reaction product of the L-cysteine tester, Specimen 6 for the 30-minute reaction product, Specimen 7 for the 10-minute reaction product of the L-tryptophan tester, and Specimen 8 for the 30-minute reaction product. A 0.1 g / 100 ml aqueous solution of each specimen was prepared, and the color value was calculated by dividing the absorbance at a wavelength of 555 nm of each aqueous solution by 0.13 (Ikeda Sugar Industry Co., Ltd., Caramel, C: / Users / Owner / Downloads / 2024 Edition Product Catalog Manuscript (Caramel) %20 %20(4).pdf). For comparison, the color value of a commercially available caramel dye (Caramel KS-45, Senba Sugar Industry Co., Ltd.) was also calculated in the same way. The results are shown in Table 2.

[0055]

Table 2

[0056] Samples 2, 4, 5, 6, 7, and 8 showed color values ​​equivalent to or better than caramel KS-45. In particular, sample 8 had a very high color value of 3.00. In the acid roasting method of caramel production, the caramelization reaction occurs at around 160°C, and is further heated to 180-200°C (see Non-Patent Literature 12). However, in the present invention, a coloring agent with a color value of 3.00 could be produced at a low temperature of 110°C and a short heating time of 30 minutes. [Industrial applicability]

[0057] The present invention reveals that the Maillard reaction, which was previously thought to occur easily in neutral to alkaline ranges, can also occur easily in very low pH ranges. Therefore, various amino acid hydrochlorides can be subjected to the Maillard reaction without neutralization, and conventionally known flavor compositions can be produced. In particular, when fructose is used, the Maillard reaction occurs very efficiently in the pH range of 0 to 2.0, providing a superior flavor production model compared to the currently actively researched roast meat-like flavor production model based on the combination of L-cysteine ​​and xylose. Furthermore, when L-cysteine ​​and L-tryptophan are used together with fructose to induce the Maillard reaction in the pH range of 0 to 2.0, a caramel-like coloring agent with a color value comparable to commercially available caramel can be produced. Current acid roasting methods for caramel require high temperatures of 160°C or higher, but by adding L-cysteine ​​and L-tryptophan to lower the pH to 0-2, it may be possible to produce caramel with a high color value at lower temperatures.

Claims

1. Organic substances having primary amino groups, or food materials containing said organic substances A method for producing a flavor composition and a caramel-like coloring agent, characterized by adjusting a solution containing sugars to a pH of 0 to 2.0 and heating it to induce a Maillard reaction.

2. A method for producing a flavor composition and a caramel-like coloring agent according to claim 1, wherein the heating temperature is 70°C to 130°C and the heating time is 10 minutes to 5 hours.

3. A method for producing a flavor composition and caramel-like colorant according to claim 1 or 2, characterized by arbitrarily mixing an organic substance having an amino group in an amount of 0.1% to 50% by weight and sugars in an amount of 0.1% to 85% by weight to form a solution.

4. A method for producing a flavor composition according to any one of claims 1 to 3, characterized in that the organic substance having an amino group contains sulfur.

5. A method for producing a flavor composition according to any one of claims 1 to 4, wherein the organic substance having an amino group and containing sulfur is selected from the group consisting of cysteine, thiamine, cystine, homocysteine, methionine, taurine, alliin, S-allylcysteine, glutathione, cystathionine, and lentinic acid.

6. A method for producing a caramel-like colorant according to any one of claims 1 to 3, characterized in that the organic substance having an amino group contains either or both cysteine ​​and tryptophan.

7. A method for producing a flavor composition and caramel-like coloring agent according to claim 1, wherein the food material of claim 1 comprises one or more selected from the group consisting of yeast, live meat, fish meat, legumes, grains, vegetables, fruits, and their dried products and extracts.

8. A method for producing a flavor composition and caramel-like coloring agent according to any one of claims 1 to 7, wherein the sugar is one or more selected from the group consisting of ribose, xylose, arabinose, glucose, mannose, fructose, maltose, lactose, sucrose, starch, and inulin.

9. A method for producing a flavor composition and a caramel-like coloring agent according to any one of claims 1 to 8, characterized in that the sugars particularly include fructose.

10. A flavor composition and a caramel-like coloring agent obtained by applying the manufacturing method described in any one of claims 1 to 9, and a food product to which these are added.

Images