Method for inhibiting browning of sorbitol-glycine system in storage process

Abstract

The invention discloses a method for inhibiting browning of a sorbitol-glycine system in a storage process, and belongs to the field of food chemistry. An accelerated storage experiment of a sorbitol-glycine system is carried out in storage environments with different oxygen concentrations, the environment with the oxygen concentration of 30% promotes oxidation pathways in the sugar alcohol and Maillard reaction, non-oxidation pathways are inhibited, generation of dicarbonyl compounds serving as key precursors for melanoids is prevented, and the stability of the melanoids is improved. Therefore, generation of color generation substances in the browning reaction is reduced. According to the method disclosed by the invention, non-enzymatic browning of a sorbitol-glycine system in the storage process is inhibited in a green and safe manner, the color stability of food containing sorbitol and glycine can be improved, the storage time is prolonged, the popularity of consumers is improved, and the method has a certain practical application value.

Description

Technical Field

[0001] The invention relates to a method for inhibiting browning of a sorbitol-glycine system during storage, and belongs to the field of food chemistry. Background Art

[0002] In the current food industry, as people's living standards improve, their requirements for food quality continue to increase, which mainly includes the color and flavor of food. During storage, food will brown, which seriously affects its color stability and produces other substances that reduce the taste, flavor and nutritional value of food, which will seriously reduce consumers' desire to buy. Non-enzymatic browning is the main factor for color deterioration in food, and the Maillard reaction is the most common reaction in non-enzymatic browning. Through the nucleophilic addition reaction of the carbonyl group of the reducing sugar and the amino group of the protein or amino acid and a series of oxidation, cyclization, dehydration, polymerization and other reactions, brown polymer macromolecule melanin is finally generated, causing food browning.

[0003] Sugar alcohols, as a low-calorie sweetener, are often added to sugar substitute foods as a substitute for reducing sugars to meet people's health needs. Sorbitol is a six-carbon sugar alcohol, usually used as a sugar substitute, and has been widely used in the food industry as a sweetener, humectant, emulsifier and excipient. At the same time, sorbitol is often used in toothpaste, skin care products and cosmetics due to its moisturizing properties, and is also widely used in the daily chemical industry. Although the Maillard reactivity of sorbitol is lower than that of reducing sugars, browning can still be observed in systems containing amino acids after high-temperature processing and long-term storage. Glycine, as a multifunctional food additive, is widely used in the food industry. Therefore, the development of a technology that can inhibit the browning of sorbitol-glycine has very important application prospects for the sugar substitute food market and the daily chemical industry. Summary of the invention

[0004] In view of the problem that the current research on browning control of products containing sorbitol-glycine is insufficient, the present invention provides a method for inhibiting browning during storage of a sorbitol-glycine system by changing the oxygen concentration. The preparation method of the present invention is simple, safe to operate, and low in cost.

[0005] The first object of the present invention is to provide a method for inhibiting browning of a sorbitol-glycine system during storage, wherein the method comprises sealing and storing the sorbitol-glycine system in an environment with an oxygen concentration of 25% to 35% (v / v); preferably, the oxygen concentration is 30% (v / v); the sorbitol-glycine system refers to a mixed system containing sorbitol and glycine.

[0006] In one embodiment, the gas composition of the environment is 25% to 35% (v / v) oxygen, and the rest is nitrogen; preferably, the gas composition of the environment is 30% (v / v) oxygen and 70% (v / v) nitrogen.

[0007] In one embodiment, the sorbitol-glycine system is prepared by dissolving sorbitol and glycine in water in a ratio of (15-25):(0.5-1.5) (w / w); the ratio of sorbitol and glycine to water is (5-10):(10-15) (w / w), preferably, the ratio of sorbitol and glycine to water is 7:10 (w / w); optionally, the pH of the sorbitol-glycine system is 6-7.

[0008] In one embodiment, the ratio of the sorbitol-glycine system to the ambient gas is 10% to 40% (v / v).

[0009] In one embodiment, the method is to place the sorbitol-glycine system in a hand-entered air bag for 25% to 35% (v / v) oxygen aeration and then store it.

[0010] In one embodiment, the aeration time is 30 to 50 minutes; preferably, the aeration time is 40 minutes.

[0011] The second object of the present invention is to provide a method for inhibiting the generation of glyoxal, methylglyoxal or 2,3-butanedione during the storage of a sorbitol-glycine system, wherein the sorbitol-glycine system is sealed and stored in an environment with an oxygen concentration of 25% to 35% v / v; the sorbitol-glycine system refers to a mixed system containing sorbitol and glycine.

[0012] In one embodiment, the gas composition of the environment is 25% to 35% (v / v) oxygen, and the rest is nitrogen; preferably, the gas composition of the environment is 30% (v / v) oxygen and 70% (v / v) nitrogen.

[0013] In one embodiment, the sorbitol-glycine system is prepared by dissolving sorbitol and glycine in water in a ratio of (15-25):(0.5-1.5) (w / w); the ratio of sorbitol and glycine to water is (5-10):(10-15) (w / w), preferably, the ratio of sorbitol and glycine to water is 7:10 (w / w); optionally, the pH of the sorbitol-glycine system is 6-7.

[0014] In one embodiment, the ratio of the sorbitol-glycine system to the ambient gas is 10% to 40% (v / v).

[0015] In one embodiment, the method is to place the sorbitol-glycine system in a hand-entered air bag for 25% to 35% (v / v) oxygen aeration and then store it.

[0016] In one embodiment, the aeration time is 30 to 50 minutes; preferably, the aeration time is 40 minutes.

[0017] A third object of the present invention is to provide a method for storing products containing a sorbitol-glycine system.

[0018] In one embodiment, the products include but are not limited to food, daily chemicals, and medical supplies.

[0019] In one embodiment, the daily chemical products include but are not limited to toothpaste, cosmetics, and skin care products.

[0020] In one embodiment, the method is to store the product containing the sorbitol-glycine system in a sealed packaging environment with an oxygen concentration of 25% to 35% (v / v); preferably, the oxygen concentration is 30% (v / v); the sorbitol-glycine system refers to a mixed system containing sorbitol and glycine.

[0021] In one embodiment, the ratio of the sorbitol-glycine system to the gas in the packaging environment is 10% to 40% (v / v).

[0022] A fourth object of the present invention is to provide the above method for inhibiting browning during storage of the sorbitol-glycine system, the above method for inhibiting the generation of glyoxal, methylglyoxal or 2,3-butanedione during storage of the sorbitol-glycine system, or the use of the above method for storing products containing the sorbitol-glycine system.

[0023] In one embodiment, the application includes but is not limited to the fields of food, daily chemicals, chemicals, and medicine.

[0024] Beneficial effects:

[0025] The method for inhibiting browning of a sorbitol-glycine system during storage provided by the present invention is to store the sorbitol-glycine system in a sealed environment at an oxygen concentration of 30% (v / v). The present invention unexpectedly discovered that an oxygen concentration of 30% (v / v) slowed down the browning of the sorbitol-glycine system during storage, and this discovery is in stark contrast to existing reports in the current technical field. This method solves the problem of browning of sugar substitutes containing sorbitol and amino acids during storage, improves their color stability, and at the same time improves the market competitiveness of related products and consumers' desire to buy. The method for inhibiting browning disclosed by the present invention is simple to operate, low in cost, and has feasibility and universality. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the A of the reaction solution at different oxygen concentrations in the present invention 420 The relationship between nm absorbance value and Maillard reaction time;

[0027] Figure 2 It is a curve diagram showing the relationship between the pH value of the reaction solution at different oxygen concentrations and the Maillard reaction time in the present invention;

[0028] Figure 3 A curve diagram showing the relationship between the fructose and glucose contents generated by the reaction solution at different oxygen concentrations and the Maillard reaction time in the present invention;

[0029] Figure 4 is the A of the reaction solution at different oxygen concentrations in the present invention 294 The relationship between nm absorbance value and Maillard reaction time;

[0030] Figure 5 A curve diagram showing the relationship between the Amadori compound generated by the reaction solution at different oxygen concentrations and the Maillard reaction time in the present invention;

[0031] Figure 6 The graph is a relationship between the fluorescence intensity and the Maillard reaction time of the reaction solution at different oxygen concentrations in the present invention, wherein A is when the oxygen concentration is 2%, B is when the oxygen concentration is 21%, and C is when the oxygen concentration is 30%;

[0032] Figure 7 The graph is a relationship between the dicarbonyl compounds accumulated and generated by the reaction solution at different oxygen concentrations and the Maillard reaction time in the present invention, wherein A is the accumulation of glyoxal, B is the accumulation of methylglyoxal, C is the accumulation of 2,3-butanedione, and D is the accumulation of 3-deoxysugar ketone. DETAILED DESCRIPTION

[0033] Unless otherwise specified, the experimental materials and drugs used in the embodiments of the present invention can be obtained through conventional purchase.

[0034] Materials involved in the following embodiments:

[0035] The experimental water used in the following examples is distilled water, sorbitol and glycine are of food grade, the chemical reagents used in the HPLC-MS analysis experiment are of chromatographic grade, and the remaining chemical reagents are of analytical grade.

[0036] The detection methods involved in the following embodiments are:

[0037] 1. A 420 nm value, A 294 The nm value detection method is as follows:

[0038] The absorbance values ​​were recorded at wavelengths λ of 420 nm and 294 nm using a UV-visible spectrophotometer.

[0039] 2. The pH value detection method is as follows:

[0040] Use a pH meter to measure the pH value of the sample after leaving it at room temperature.

[0041] 3. High pressure ion chromatography test conditions are as follows:

[0042] The mobile phases were 0.1 mol / L sodium acetate solution and 250 mmol / L NaOH solution respectively; the chromatographic conditions were: 2% NaOH solution from 0 to 13 min, a linear gradient from 2% NaOH to 80% NaOH from 13 to 14 min, and 80% NaOH to the end point from 14 to 23 min; the flow rate was 10.5 mL / min.

[0043] 4. The detection method of Amadori compounds is as follows:

[0044] Amadori compounds were detected using multiple reaction monitoring (MRM) in positive ion mode with the following parameters:

[0045] Entrance potential (EP): 10 V; spray voltage: 5500 V; collision energy (CE): 15 V; ion source temperature: 600°C; source gas flow rate: 15 L / min; auxiliary gas flow rate: 18 L / min.

[0046] 5. The fluorescence intensity detection method is as follows:

[0047] The fluorescence intensity was detected by a fluorescence spectrophotometer, the excited state wavelength was 347 nm, and the measurement wavelength range was 300-600 nm.

[0048] 6. The MS / MS ion information used to analyze the four dicarbonyl compounds is as follows:

[0049] Glyoxal: parent ion (m / z) is 131, and daughter ions (m / z) include 92 (m / z, quantitative ion) and 65 (m / z, qualitative ion);

[0050] Methylglyoxal: parent ion (m / z) is 145, and daughter ions (m / z) include 91.7 (m / z, quantitative ion) and 65 (m / z, qualitative ion);

[0051] 2,3-Butanedione: parent ion (m / z) is 159, daughter ions (m / z) are 117.5 (m / z, quantitative ion), 79 (m / z, qualitative ion);

[0052] 3-Deoxyaldehyde ketone: parent ion (m / z) is 235.1, daughter ions (m / z) are 217.1 (m / z, quantitative ion), 199.1 (m / z, qualitative ion), 181.1 (m / z, qualitative ion).

[0053] Chromatographic column: Agilent LiChrospher C18 (250mm×4.6mm, 5μm) column; column temperature: 40°C; UV detection wavelength: 320nm; injection volume: 10μL; flow rate: 1mL / min; mobile phase A: acetonitrile; mobile phase B: 0.1% formic acid aqueous solution, gradient elution.

[0054] 7. The detection method of volatile flavor substances is as follows:

[0055] The volatile flavor substances were detected by gas chromatography-mass spectrometry (GC-MS). The chromatographic detection conditions were as follows:

[0056] GC conditions: A DB-Max column (30m×0.25mm×0.25μm, Folsom J&W Scientific, USA) was used to separate volatile compounds. The column temperature program was as follows: initially at 38°C for 6 min, then heated to 105°C at a rate of 6°C / min, then heated to 160°C at a rate of 10°C / min, then heated to 220°C at a rate of 15°C / min, and then held for 5 min. The carrier gas was high-purity helium at a flow rate of 1.8 mL / min.

[0057] Mass spectrometry conditions: electron impact mode, electron energy 70 eV, emission current 35 mA. Mass spectrometry scanning was performed in the range of 35-450 m / z, with a scanning rate of 4.45 times / s. The ion source and interface temperatures were both 250 °C.

[0058] Example 1: Effect of 30% oxygen concentration on browning of sorbitol-glycine system during storage

[0059] The specific steps are as follows:

[0060] (1) dissolving 100 g of sorbitol and 5 g of glycine in 150 g of water, and adjusting the pH of the mixed solution to 6.8 to form a sorbitol-glycine system;

[0061] (2) selecting an oxygen concentration of 30% and a nitrogen concentration of 70% as the reaction environment, placing the sorbitol-glycine system obtained in step (1) in a hand-entry air bag, sealing the air bag, adjusting the oxygen concentration to 30%, aerating for 40 minutes, and using an oxygen probe to monitor the oxygen concentration in the air bag in real time;

[0062] (3) The system in step (2) was transferred to a constant temperature incubator for an accelerated storage experiment at 60°C. One batch was taken out every week for testing during the first 4 weeks. After long-term storage for 6 months, the samples were tested and observed again.

[0063] The detection method is: cool the sample in an ice bath to terminate the reaction. Determine the corresponding A 420 nm value, pH value, reducing sugar concentration, A 294 nm value, Amadori compound concentration, fluorescence intensity (347nm excitation wavelength, 300-600nm wavelength range), dicarbonyl compound (methylglyoxal, glyoxal, 2,3-butanedione, 3-deoxyglycoside ketone) concentration, volatile flavor compound concentration.

[0064] Example 2: Effect of 2% oxygen concentration on browning during storage of sorbitol-glycine system

[0065] Specific implementation method is the same as Example 1, except that the oxygen concentration in step (2) is adjusted to 2% and the nitrogen concentration is adjusted to 98%.

[0066] Example 3: Effect of 21% oxygen concentration on browning during storage of sorbitol-glycine system

[0067] Specific implementation method is the same as Example 1, except that the oxygen concentration in step (2) is adjusted to 21% and the nitrogen concentration is adjusted to 79%.

[0068] The results are as follows:

[0069] The present invention utilizes the absorbance at 420nm wavelength (A 420 nm) to determine the non-enzymatic browning degree of the sorbitol-glycine system. Figure 1 As shown, when the storage time was 180 days, the absorbance of the reaction solution in an environment with an oxygen concentration of 30% was 0.474 (diluted 4 times), which was significantly lower than the absorbance under 2% oxygen (0.644). After long-term storage, the Maillard reaction product in an environment with an oxygen concentration of 30% was significantly lower than that in an environment with an oxygen concentration of 2% and 21% (Table 1).

[0070] Table 1 A of the reaction solution at different times and different oxygen concentrations 420 nm absorbance value

[0071]

[0072] The relationship between pH value and reaction time of the three reaction solutions at different oxygen concentrations is as follows: Figure 2As shown, the pH value of the storage environment with 30% oxygen concentration was significantly lower than that of the storage environment with 2% oxygen concentration at 21, 28 and 180 days. When the storage time was 180 days, the pH value of the reaction solution in the environment with 30% oxygen concentration was 4.62, which was significantly lower than the pH value under 2% oxygen (7.05), indicating that 30% oxygen concentration can slow down the Maillard reaction rate (Table 2).

[0073] Table 2 pH values ​​of the reaction solution at different times and different oxygen concentrations

[0074]

[0075] High pressure ion chromatography showed that when the storage time was 28 days, the reducing sugar concentration at 30% oxygen concentration was 610.03 mg / L, and at 2% oxygen concentration was 553.23 mg / L. The reducing sugar (glucose and fructose) content at 21% and 30% oxygen concentrations was significantly higher than that at 2% micro-oxygen concentration, indicating that the increase in oxygen concentration promoted the oxidation of sorbitol to a certain extent ( Figure 3 , Table 3). Amadori compounds ( Figure 5 , Table 5) and 3-deoxysugar ketone ( Figure 7 D, Table 6) also showed the same trend as reducing sugars.

[0076] Table 3 Reducing sugar concentration of reaction solution at different time and different oxygen concentration (mg / L)

[0077]

[0078] The present invention utilizes the absorbance at 294nm wavelength (A 294 nm) to detect the intermediate products of the Maillard reaction. Figure 4 As shown in the figure, when the storage time is 14, 21, and 28 days, the A 294 The nm values ​​were significantly lower than those at 21% and 2% oxygen concentrations (Table 4).

[0079] Table 4 A of the reaction solution at different times and different oxygen concentrations 294 nm absorbance value

[0080]

[0081] Table 5 Amadori compound concentrations (mg / L) of the reaction solution at different times and different oxygen concentrations

[0082]

[0083]

[0084] Table 6 3-deoxysugar ketone concentration (mg / L) of reaction solution at different time and different oxygen concentration

[0085]

[0086] The change in fluorescence intensity can reflect the degree of Maillard reaction. The present invention detects the fluorescence intensity at different oxygen concentrations at different times by using a fluorescence spectrophotometer, such as Figure 6 When the oxygen concentration was 30%, the fluorescence intensity was significantly lower than that of 2% and 21% at storage time of 7, 14, 21, and 28 days.

[0087] Dicarbonyl compounds are considered to be the key precursor products for the formation of melanoidins. The present invention detects dicarbonyl compounds in the sorbitol-glycine system under different oxygen concentrations, including glyoxal, methylglyoxal, 2,3-butanedione ( Figure 7 A~C, Table 7~Table 9). The results showed that when the storage time was 28 days, the glyoxal, methylglyoxal and 2,3-butanedione, which reflected the generation of the intermediate products, were 222.89 mg / L, 9.61 mg / L and 0.071 mg / L respectively when the oxygen concentration was 30%, 275.74 mg / L, 10.51 mg / L and 0.25 mg / L respectively when the oxygen concentration was 21%, and 380.98 mg / L, 11.05 mg / L and 0.53 mg / L respectively when the oxygen concentration was 2%, which were significantly lower under the condition of 30% oxygen than those under the condition of 2% and 21% oxygen.

[0088] Table 7 Glyoxal concentrations (mg / L) of reaction solution at different times and different oxygen concentrations

[0089]

[0090] Table 8: Methylglyoxal concentrations (mg / L) of the reaction solution at different times and different oxygen concentrations

[0091]

[0092] Table 9 2,3-Butanedione concentration (mg / L) of reaction solution at different times and different oxygen concentrations

[0093]

[0094]

[0095] Table 10 is an analysis of volatile flavor compounds generated by the reaction solution at different times and different oxygen concentrations in the present invention. Pyrazines are a class of volatile compounds containing heterocyclic nitrogen atoms, usually generated by the Maillard reaction. The generation of pyrazine compounds in the reaction solution with an oxygen concentration of 30% is significantly reduced, indicating that the occurrence of the Maillard reaction is inhibited at an oxygen concentration of 30%. Compared with the reaction solution at an oxygen concentration of 2%, the acid substances at an oxygen concentration of 30% are significantly increased. The acid substances bring the reaction system to a more acidic environment, which is more unfavorable for the occurrence of the Maillard reaction. Ketones are key intermediates in the Maillard reaction, usually with a fresh fragrance, milky fragrance and fruity fragrance. Acid substances and ketone substances are both products of sugar oxidation reactions, and their content is higher when the oxygen concentration is high.

[0096] Table 10 Analysis of volatile flavor compounds generated under different oxygen concentrations

[0097]

[0098] Note: a, b represent p<0.05.

[0099] In summary, the A that reflects the generation of intermediate products 294 The nm value, fluorescence intensity and three dicarbonyl compounds (glyoxal, methylglyoxal, 2,3-butanedione) are significantly lower than when the oxygen concentration is 2% and 21% under 30% oxygen conditions, and gradually decrease with the increase of oxygen concentration, which is consistent with the trend presented by the color. Combined with the chart, it can be determined that when the oxygen concentration is 30%, the best effect of inhibiting the browning of sorbitol and glycine is. It can be seen that this method inhibits the reaction by inhibiting the generation of key intermediates in the Maillard reaction, prevents the non-enzymatic browning of sorbitol-glycine, and effectively reduces the generation of its color.

[0100] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for inhibiting browning during storage of a sorbitol-glycine system, characterized in that: The method comprises the following steps: sealing and storing the sorbitol-glycine system in an environment with an oxygen concentration of 25% to 35% v / v; the sorbitol-glycine system refers to a mixed system containing sorbitol and glycine.

2. The method according to claim 1, characterized in that The ratio of the sorbitol-glycine system to the gas in the environment is 10% to 40% v / v.

3. The method according to claim 1, characterized in that The method comprises the following steps: placing the sorbitol-glycine system in a hand-in air bag, aerating the bag with 25% to 35% v / v oxygen, and then sealing the bag for storage.

4. The method according to claim 3, characterized in that The aeration time is 30 to 50 minutes.

5. A method for inhibiting the formation of glyoxal, methylglyoxal or 2,3-butanedione during storage of a sorbitol-glycine system, characterized in that: The method comprises the following steps: sealing and storing the sorbitol-glycine system in an environment with an oxygen concentration of 25% to 35% v / v; the sorbitol-glycine system refers to a mixed system containing sorbitol and glycine.

6. The method according to claim 5, characterized in that The ratio of the sorbitol-glycine system to the gas in the environment is 10% to 40% v / v.

7. A method for storing a product containing a sorbitol-glycine system, characterized in that: The method comprises the following steps: sealing and storing the product containing the sorbitol-glycine system in a packaging environment with an oxygen concentration of 25% to 35% v / v; the sorbitol-glycine system refers to a mixed system containing sorbitol and glycine.

8. The method according to claim 7, characterized in that The ratio of the sorbitol-glycine system to the gas in the packaging environment is 10% to 40% v / v.

9. The method according to claim 7, characterized in that: The products include but are not limited to food, daily chemicals, and medical supplies; preferably, the daily chemicals include but are not limited to toothpaste, cosmetics, and skin care products.

10. Application of the method according to claims 1 to 9 in the fields of food, daily chemicals, chemical industry and medicine.

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