A soybean flavor peptide for inhibiting acid stimulation of food, and preparation method and application thereof

Abstract

The present application relates to the field of food processing technology, and specifically discloses a soybean flavor peptide that inhibits the sour stimulation of food, and its preparation method and application. The present application uses defatted soybeans as the main raw material, inoculates Aspergillus oryzae for fermentation, and then adds a composite protease for directional enzymatic hydrolysis, wherein Aspergillus oryzae metabolizes to produce Aspergillus oryzae protease during fermentation, and with the additional addition of papain and neutral protease, the soybean protein is subjected to directional enzymatic hydrolysis to obtain a soybean flavor peptide product rich in small molecule flavor peptides; the soybean flavor peptide produced by the present application is tested for application in various types of vinegar and foods with sour taste as the main flavor, such as lemon chicken feet, and it has a significant inhibitory effect on the sour stimulation of the product and the burning sensation of the sour taste on the esophagus, which can make the sour taste of the product tend to be soft and mellow, and improve the comfort of the sour taste in the mouth.

Description

Technical Field

[0001] The present application relates to the field of food processing technology, and in particular to a soybean flavor peptide capable of inhibiting the acid stimulation of food, and a preparation method and application thereof. Background Art

[0002] As one of the five basic flavors, sourness occupies an important position in the food industry. In addition to condiments such as vinegar that are produced and sold specifically to provide sourness, many local delicacies and snack foods also use sourness as their main selling point and characteristic flavor. Taking vinegar as an example, domestic vinegar has many subdivided categories based on the raw materials used, origin, production method, product use and other characteristics. The sourness is mainly provided by substances such as acetic acid produced during the fermentation of grain raw materials. However, due to problems such as improper control of production technology and raw material selection in some vinegar products, the products contain too much acetic acid and other substances, or artificial synthetic acidulants are added for cost control and other reasons, which may cause the vinegar to have a harsh sour taste, strong irritation in the mouth, and too heavy sour taste, which will affect the product quality and application performance.

[0003] In addition to vinegar, some snack foods also have sourness as their main characteristic flavor. For example, lemon chicken feet are mainly made from chicken feet and lemon juice, and are deeply loved by consumers for their refreshing sweet and sour flavor. However, this type of food is also limited by cost, raw materials, technology and other reasons. Some products have too strong sour taste, and the characteristic flavor is too sour for some consumers, thus affecting the consumer's eating experience. For this type of condiments, dishes or snack foods with sourness as the main flavor, the industry currently has a way to reduce the sour stimulation and increase the sourness. On the one hand, reduce the addition of sour substances such as vinegar and fruit juice, and on the other hand, increase other flavor substances such as white sugar, salt, soy sauce, etc. to balance the overall flavor of the food and reduce the prominence of the sour taste.

[0004] On the one hand, the above method may increase the overall production cost of the product, on the other hand, the effect of suppressing the sour and astringent stimulation cannot be guaranteed, and it may also destroy the overall taste and flavor of the product itself, resulting in a decline in product quality. Summary of the invention

[0005] The purpose of the present application is to overcome the deficiencies of the above-mentioned prior art and to provide a soybean flavor peptide that inhibits the acid stimulation of food and a preparation method and application thereof.

[0006] To achieve the above purpose, the technical solution adopted by this application is:

[0007] The present application provides a method for preparing soybean flavor peptides, comprising the following steps:

[0008] S1. Fully mixing the steamed soybeans / defatted soybeans and Aspergillus oryzae, and fermenting them to obtain a fermented product;

[0009] S2, adding water to the fermented product, stirring and shearing, to obtain a slurry;

[0010] S3, mixing the ground material and the composite protease for enzymolysis to obtain an enzymolysis solution, inactivating the enzyme, centrifuging the inactivated enzymolysis solution, filtering the supernatant, and concentrating it into a solid to obtain soybean flavor peptides;

[0011] The composite protease comprises papain and neutral protease.

[0012] The present application uses soybeans / defatted soybeans as raw materials, and produces soybean flavor peptides through processes such as Aspergillus oryzae fermentation, blending, composite protease hydrolysis, and concentration. After Aspergillus oryzae is inoculated into soybeans / defatted soybeans, a large amount of Aspergillus oryzae protease is produced during the fermentation period, which, combined with the additionally added high-temperature neutral protease and papain, allows the protein in the soybeans to be fully enzymatically hydrolyzed into soybean flavor peptides of a specific molecular weight. The present application uses Aspergillus oryzae protease produced by the fermentation metabolism of Aspergillus oryzae, combined with papain and high-temperature neutral protease, to hydrolyze soybean protein to obtain small molecule peptides that have a flavoring effect, can significantly inhibit the strong acid stimulation in food and condiments, and soften the sour taste.

[0013] Among them, the present application adds papain and high-temperature neutral protease to the fermented material after fermentation is completed to deeply hydrolyze the soybean protein, the total nitrogen content of the product reaches more than 60%, the desalted dry basis peptide content reaches more than 35%, and the peptide molecule distribution is mainly 200 to 1000 Daltons, accounting for more than 40%.

[0014] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, the neutral protease includes a high-temperature neutral protease.

[0015] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, the mass ratio of papain to neutral protease is 1:(2-5).

[0016] The composite protease in the above mass ratio range can be used in this application to perform directional enzymatic hydrolysis on soybean protein to obtain a soybean flavor peptide product rich in small molecule flavor peptides. The peptide molecule distribution of the product is mainly 200-1000 Daltons, accounting for more than 40%; the total nitrogen content is more than 60%, and the desalted dry base peptide content is more than 35%. The above soybean flavor peptide product can significantly inhibit the strong acid stimulation in food and condiments, making the sour taste soft.

[0017] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, in step S1, the step of steaming soybeans / defatted soybeans comprises:

[0018] Add 98-99% soybeans / defatted soybeans in a mass ratio of 1.5-2.0 times drinking water at 85-90°C, soak for 25-30 minutes, drain the water and place in a high-pressure cooking pot, cook for 15-25 minutes at a temperature of 110-120°C and a pressure of 110-130KPa, take out, drain the water and cool to room temperature to obtain the cooked soybeans / defatted soybeans.

[0019] In some specific embodiments, defatted soybeans must meet the following requirements: moisture ≤ 12.0%; crude protein (wet basis) ≥ 46.0%; crude fat (dry basis) ≤ 2.0%; ash (dry basis) ≤ 6.5%; soybeans must meet the following requirements: moisture ≤ 12.0%; crude protein (wet basis) ≥ 38.0%; ash (dry basis) ≤ 6.5%; crude fat (dry basis) ≤ 18.0%; other hygiene and safety indicators must meet the relevant requirements of GB / T13382.

[0020] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, in the step S1, the mass ratio of the steamed soybeans / defatted soybeans to Aspergillus oryzae is 1:(0.00015-0.00025).

[0021] The present invention uses soybeans / defatted soybeans as raw materials, inoculates Aspergillus oryzae for fermentation, and uses Aspergillus oryzae protease as one of the enzyme sources for later hydrolysis. In addition, the Aspergillus oryzae protease produced by Aspergillus oryzae fermentation metabolism can be used to prepare soybean flavor peptides with a specific molecular weight that can inhibit the sour and astringent taste of food.

[0022] In some specific embodiments, the fermentation time is 38 to 42 hours.

[0023] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, in step S1, the fermentation step includes:

[0024] The soybeans / defatted soybeans are fully stirred at 16-17h, 23-24h, and 28-29h after the start of fermentation. The temperature of the soybeans / defatted soybeans is maintained at 32-35°C from the start of fermentation to the first stirring, 27-32°C from the first stirring to the second stirring, 27-32°C from the second stirring to the third stirring, and 26-29°C from the third stirring to the completion of fermentation.

[0025] In some specific embodiments, the soybean / defatted soybean layer is not more than 3 cm in height during the fermentation process.

[0026] In some specific embodiments, during the soybean / defatted soybean fermentation process, all materials should be stirred as evenly as possible to avoid excessively high temperatures in some areas of the materials that affect the fermentation effect.

[0027] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, in step S2, the weight ratio of the fermentation product to water is 1:(2-2.5).

[0028] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, in step S2, the water temperature is 55-65° C., and the stirring time is 5-8 min;

[0029] The shearing speed is 12000-15000 r / min, and the shearing time is 5-10 min.

[0030] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, in step S3, the inoculation amount of the composite protease is 1.5-2.0%.

[0031] As a preferred embodiment of the method for preparing soybean flavor peptides described in the present application, in step S3, the centrifugal speed is 8000-11000 r / min, the centrifugal temperature is 24-25° C., and the centrifugal time is 10-20 min;

[0032] The concentration temperature is 58 to 65°C, the concentration pressure is -0.1 to -0.08 MPa, and the concentration time is 10 to 20 minutes.

[0033] In some specific embodiments, the present application uses a circulating water vacuum pump to evacuate to a vacuum degree of -0.1 to -0.08 MPa to accelerate the concentration rate.

[0034] In some specific embodiments, in step S3, the pH of the enzymatic hydrolysis solution is 6.5-7.0.

[0035] In step S3, the enzymatic hydrolysis conditions are as follows: the ground material and the composite protease are mixed and placed in a water bath shaker at 58-62° C. for heating and shaking for 9-11 hours.

[0036] In some specific embodiments, the enzymatic hydrolysis solution needs to be continuously shaken during the enzymatic hydrolysis process.

[0037] In some specific embodiments, the enzyme inactivation condition is: placing the enzymatic solution in a boiling water bath to inactivate the enzyme for 15 to 20 minutes.

[0038] The present application also provides a soybean flavor peptide prepared by the preparation method of the above soybean flavor peptide, in which small molecule peptides with a molecular weight of 200 to 1000 Da account for more than 40%.

[0039] The present application also provides the use of the soybean flavor peptide in inhibiting the acid stimulation of food.

[0040] Small molecule peptides with a molecular weight of 200 to 1000 Da have the effect of inhibiting the sour taste in food, and the higher the concentration of this molecular weight peptide segment, the more obvious the effect of inhibiting acidity.

[0041] It has been found through experiments that the soybean flavor peptides obtained by the method of the present application through the directed enzymatic hydrolysis of soybean protein have a molecular weight in the range of 200 to 1000 Da and a content of more than 40%, which has the effect of inhibiting the sour taste, and mainly has a significant inhibitory effect on the sour stimulation, sour astringency and sour burning sensation in food. Compared with the method of reducing the use of sour materials or adding other flavor substances to inhibit the sour stimulation and sour astringency, the soybean flavor peptides produced by the present application have less effect on the original characteristic flavors of products such as vinegar and lemon chicken feet, and significantly inhibit the sour stimulation of the product, and can significantly improve the sour and soft feeling of the product.

[0042] Compared with the prior art, this application has the following beneficial effects:

[0043] The present application provides a soybean flavor peptide that inhibits the sour stimulation of food, and its preparation method and application. The present application uses soybean / defatted soybean as the main raw material, inoculates Aspergillus oryzae for fermentation, and adds a composite protease for directional enzymatic hydrolysis, wherein Aspergillus oryzae is metabolized during fermentation to produce Aspergillus oryzae protease, and the soybean protein is subjected to directional enzymatic hydrolysis with additional papain and neutral protease to obtain a soybean flavor peptide product rich in small molecule flavor peptides; the desalted dry protein content of the soybean flavor peptide produced by the present application is above 60%, and the desalted dry peptide content is ≥35%, wherein the distribution of peptide molecules is mainly 200 to 1000 Daltons, accounting for more than 40%. The soybean flavor peptide produced by the present application has been tested for application in various types of vinegar and foods with sour taste as the main flavor, such as lemon chicken feet. It has a significant inhibitory effect on the sour stimulation of the product and the burning sensation of the sour taste on the esophagus, and can make the sour taste of the product tend to be soft and mellow, and improve the comfort of the sour taste in the mouth. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a sensory score result diagram of adding 0.05% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to white vinegar;

[0045] Figure 2 This is a sensory score result diagram of adding 0.1% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to white vinegar;

[0046] Figure 3 It is a sensory score result diagram of adding 0.05% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 into aged vinegar;

[0047] Figure 4 This is a sensory score result diagram of adding 0.1% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to aged vinegar;

[0048] Figure 5 It is a sensory score result diagram of adding 0.05% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to rice vinegar;

[0049] Figure 6 It is a sensory score result diagram of adding 0.1% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 into rice vinegar;

[0050] Figure 7 This is a sensory score result diagram of adding 0.3% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to lemon chicken feet;

[0051] Figure 8 This is a sensory score result diagram of adding 0.5% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to lemon chicken feet;

[0052] Fig. 9 The results are as follows: the peptide content (desalted dry basis) and the proportion of 200-1000 Da molecular weight peptide segments of the products of Examples 1-4 and Comparative Examples 1-8. DETAILED DESCRIPTION

[0053] In order to better illustrate the purpose, technical solutions and advantages of the present application, the present application will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0054] In the following examples and comparative examples, the experimental methods used are conventional methods unless otherwise specified, and the materials, reagents, etc. used are all commercially available unless otherwise specified, and the components and raw materials used in each parallel experiment are of the same type.

[0055] The defatted soybeans in the following examples and comparative examples are low-temperature edible defatted soybeans.

[0056] Defatted soybeans must meet the following requirements: moisture ≤ 12.0%; crude protein (wet basis) ≥ 46.0%; crude fat (dry basis) ≤ 2.0%; ash (dry basis) ≤ 6.5%; other hygiene and safety indicators must comply with the relevant requirements of GB / T13382.

[0057] The high temperature neutral protease used in the following examples and comparative examples is a commercially available neutral protease with an enzyme activity unit of 50,000-400,000 μ / g.

[0058] Example 1: A soybean flavor peptide for inhibiting the acid stimulation of food and a preparation method thereof

[0059] This embodiment provides a method for preparing soybean flavor peptide, comprising the following steps:

[0060] 1. Soak defatted soybeans in 90℃ drinking water 1.5 times their mass for 25 minutes, drain the water and put them into a high pressure cooker, cook at 110℃ and 120KPa for 15 minutes, take out, drain the water and let cool to room temperature;

[0061] 2. Weigh the defatted soybeans after cooking at a ratio of defatted soybeans to Aspergillus oryzae koji = 1:0.00015 and add koji (0.015% of the total mass of defatted soybeans), and stir well;

[0062] 3. Add Aspergillus oryzae and spread the defatted soybeans evenly in the fermentation equipment, keep the average thickness not more than 3 cm, put them into the fermentation cabinet, control the temperature at 32°C to start fermentation, and the total fermentation time is 38 hours; take out the fermentation equipment 16 hours after the start of fermentation, stir the fermented material evenly, put it into the fermentation cabinet and continue to ferment at 27°C for 7 hours, take it out and stir it for the second time; then continue to ferment at 27°C for 5 hours, take it out and stir it for the third time, and then ferment at 26°C until the end;

[0063] 4. After fermentation is completed, add 60°C drinking water 2.5 times the total mass of the fermented material, transfer to a clean conical flask and stir for 5 minutes, then use a high-speed shearing machine at a speed of 12000r / min for 5 minutes until the material becomes a uniform slurry to obtain a ground slurry;

[0064] 5. Use 1 mol / L hydrochloric acid solution to adjust the pH of the milled slurry to 6.0, add composite protease (papain: high temperature neutral protease = 1:2) at 1.5% of the raw material mass, shake well and perform enzymolysis at 58°C in a water bath shaker for 9 hours;

[0065] 6. After the enzymatic hydrolysis is completed, take it out and immediately bathe it in boiling water for 15 minutes to inactivate the enzyme;

[0066] 7. Place the enzymatic hydrolysate in a centrifuge and centrifuge at 10,000 r / min and 24°C for 15 minutes. Then take the supernatant and filter it through a 200-mesh filter cloth. Then place it in a vacuum rotary evaporator and concentrate it in a water bath at 60°C and -0.08MPa vacuum to a solid content of 35%, which is the finished product.

[0067] In this embodiment, the defatted soybeans used have a protein content of 47%, a moisture content of 11%, an ash content of 5.8%, and a crude fat content of 1.1%.

[0068] Example 2: A soybean flavor peptide for inhibiting the acid stimulation of food and a preparation method thereof

[0069] This embodiment provides a method for preparing soybean flavor peptide, comprising the following steps:

[0070] 1. Soak defatted soybeans in 90℃ drinking water 1.5 times their mass for 25 minutes, drain the water and put them into a high pressure cooker, cook at 110℃ and 120KPa for 15 minutes, take out, drain the water and let cool to room temperature;

[0071] 2. Weigh the defatted soybeans after cooking at a ratio of defatted soybeans to Aspergillus oryzae koji = 1:0.00015 and add koji (0.015% of the total mass of defatted soybeans), and stir well;

[0072] 3. Add Aspergillus oryzae and spread the defatted soybeans evenly in the fermentation equipment, keeping the average thickness no more than 3cm, put them into the fermentation cabinet, control the temperature at 32℃ to start fermentation, and the total fermentation time is 38h. Take out the fermentation equipment 16h after the start of fermentation, stir the fermented material thoroughly and evenly, then put it into the fermentation cabinet to continue fermenting at 27℃ for 7h, take it out for the second stirring; then continue to ferment at 27℃ for 5h, take it out for the third stirring, and then ferment at 26℃ until the end;

[0073] 4. After the fermentation is completed, add 60°C drinking water 2.5 times the total mass of the fermentation, transfer to a clean conical flask and stir for 5 minutes, then use a high-speed shearing machine at a speed of 12000r / min for 5 minutes until the material becomes a uniform slurry to obtain a ground slurry;

[0074] 5. Use 1 mol / L hydrochloric acid solution to adjust the pH of the milled slurry to 6.0, add composite protease (papain: high temperature neutral protease = 1:5) at 2.0% of the raw material mass, shake well and perform enzymolysis at 62°C in a water bath shaker for 11 hours;

[0075] 6. After the enzymatic hydrolysis is completed, take it out and immediately bathe it in boiling water for 15 minutes to inactivate the enzyme;

[0076] 7. Place the enzymatic hydrolysate in a centrifuge and centrifuge at 10,000 r / min and 24°C for 15 minutes. Then take the supernatant and filter it through a 200-mesh filter cloth. Then place it in a vacuum rotary evaporator and concentrate it in a water bath at 60°C and -0.08MPa vacuum to a solid content of 35%, which is the finished product.

[0077] In this embodiment, the defatted soybeans used have a protein content of 47%, a moisture content of 11%, an ash content of 5.8%, and a crude fat content of 1.1%.

[0078] Example 3: A soybean flavor peptide for inhibiting the acid stimulation of food and a preparation method thereof

[0079] This embodiment provides a method for preparing soybean flavor peptide, comprising the following steps:

[0080] 1. Soak defatted soybeans in 90℃ drinking water 1.5 times their mass for 25 minutes, drain the water and put them into a high pressure cooker, cook at 110℃ and 120KPa for 15 minutes, take out, drain the water and let cool to room temperature;

[0081] 2. Weigh the defatted soybeans after cooking at a ratio of defatted soybeans to Aspergillus oryzae koji = 1:0.00025 and add koji (0.025% of the total mass of defatted soybeans), and stir well;

[0082] 3. Add Aspergillus oryzae and spread the defatted soybeans evenly in the fermentation equipment, keeping the average thickness no more than 3cm, put them into the fermentation cabinet, control the temperature at 35℃ to start fermentation, and the total fermentation time is 42h. Take out the fermentation equipment 17h after the start of fermentation, stir the fermented material thoroughly and evenly, put it into the fermentation cabinet and continue to ferment at 31℃ for 7h, take it out and stir it for the second time; then continue to ferment at 31℃ for 5h, take it out and stir it for the third time, and then ferment at 29℃ until the end;

[0083] 4. After the fermentation is completed, add 60°C drinking water 2.5 times the total mass of the fermentation, transfer to a clean conical flask and stir for 5 minutes, then use a high-speed shearing machine at a speed of 12000r / min for 5 minutes until the material becomes a uniform slurry to obtain a ground slurry;

[0084] 5. Use 1 mol / L hydrochloric acid solution to adjust the pH of the milled slurry to 6.0, add composite protease (papain: high temperature neutral protease = 1:2) at 1.5% of the raw material mass, shake well and perform enzymolysis at 58°C in a water bath shaker for 9 hours;

[0085] 6. After the enzymatic hydrolysis is completed, take it out and immediately bathe it in boiling water for 15 minutes to inactivate the enzyme;

[0086] 7. Place the enzymatic hydrolysate in a centrifuge and centrifuge at 10,000 r / min and 24°C for 15 minutes. Then take the supernatant and filter it through a 200-mesh filter cloth. Then place it in a vacuum rotary evaporator and concentrate it in a water bath at 60°C and -0.08MPa vacuum to a solid content of 35%, which is the finished product.

[0087] In this embodiment, the defatted soybeans used have a protein content of 47%, a moisture content of 11%, an ash content of 5.8%, and a crude fat content of 1.1%.

[0088] Example 4: A soybean flavor peptide for inhibiting the acid stimulation of food and a preparation method thereof

[0089] This embodiment provides a method for preparing soybean flavor peptide, comprising the following steps:

[0090] 1. Soak defatted soybeans in 85℃ drinking water 2.0 times their mass for 30 minutes, drain the water and put them into a high pressure cooker, cook at 120℃ and 130KPa for 25 minutes, take them out, drain the water and let them cool to room temperature;

[0091] 2. Weigh the defatted soybeans after cooking at a ratio of defatted soybeans to Aspergillus oryzae koji = 1:0.00015 and add koji (0.015% of the total mass of defatted soybeans), and stir well;

[0092] 3. Add Aspergillus oryzae and spread the defatted soybeans evenly in the fermentation equipment, keeping the average thickness no more than 3cm, put them into the fermentation cabinet, control the temperature at 32℃ to start fermentation, and the total fermentation time is 38h. Take out the fermentation equipment 17h after the start of fermentation, stir the fermented material thoroughly and evenly, then put it into the fermentation cabinet to continue fermenting at 27℃ for 7h, take it out and stir it for the second time; then continue to ferment at 27℃ for 5h, take it out and stir it for the third time, and then ferment at 26℃ until the end;

[0093] 4. After the fermentation is completed, add 60°C drinking water twice the total mass of the fermentation, transfer to a clean conical flask and stir for 8 minutes, then use a high-speed shearing machine at a speed of 15000r / min for 10 minutes until the material becomes a uniform slurry to obtain a ground slurry;

[0094] 5. Use 1 mol / L hydrochloric acid solution to adjust the pH of the milled slurry to 7.0, add composite protease (papain: high temperature neutral protease = 1:2) at 1.5% of the raw material mass, shake well and perform enzymolysis at 62°C in a water bath shaker for 11 hours;

[0095] 6. After the enzymatic hydrolysis is completed, take it out and immediately bathe it in boiling water for 20 minutes to inactivate the enzyme;

[0096] 7. Place the enzymatic hydrolysate in a centrifuge and centrifuge at 8000r / min and 25°C for 20min. Then take the supernatant and filter it through a 200-mesh filter cloth. Then place it in a vacuum rotary evaporator and concentrate it in a water bath at 62°C and -0.08MPa vacuum to a solid content of 38%, which is the finished product.

[0097] In this embodiment, the defatted soybeans used have a protein content of 47%, a moisture content of 11%, an ash content of 5.8%, and a crude fat content of 1.1%.

[0098] Comparative Example 1

[0099] This comparative example provides a method for preparing soybean flavor peptide, comprising the following steps:

[0100] 1. Soak defatted soybeans in 90℃ drinking water (1.5 times its mass) for 25 minutes, drain the water and put them into a high pressure cooker, cook them at 110℃ and 120KPa for 15 minutes, take them out, drain the water and let them cool to room temperature;

[0101] 2. Add 60℃ drinking water of 2.5 times the total mass of the defatted soybeans to a clean conical flask and stir for 5 minutes. Then use a high-speed shearing machine at a speed of 12000r / min for 5 minutes until the material becomes a uniform slurry to obtain a ground slurry;

[0102] 3. Adjust the pH of the milled slurry to 6.0 with 1 mol / L hydrochloric acid solution, add compound protease at 1.5% of the raw material mass, shake well and perform enzymolysis at 58°C in a water bath shaker for 9 hours;

[0103] 4. After the enzymatic hydrolysis is completed, take it out and immediately bathe it in boiling water for 15 minutes to inactivate the enzyme;

[0104] 5. Place the enzymatic hydrolysate in a centrifuge and centrifuge at 10,000 r / min and 24°C for 15 minutes. Then take the supernatant and filter it through a 200-mesh filter cloth. Then place it in a vacuum rotary evaporator and concentrate it in a water bath at 60°C and -0.08MPa vacuum to a solid content of 35%, which is the finished product.

[0105] In this comparative example, the defatted soybeans used had a protein content of 47%, a moisture content of 11%, an ash content of 5.8%, and a crude fat content of 1.1%.

[0106] Comparative Example 2

[0107] This comparative example provides a method for preparing soybean flavor peptide, comprising the following steps:

[0108] 1. Soak defatted soybeans in 90℃ drinking water 1.5 times their mass for 25 minutes, drain the water and put them into a high pressure cooker, cook at 110℃ and 120KPa for 15 minutes, take out, drain the water and let cool to room temperature;

[0109] 2. Weigh the defatted soybeans after cooking at a ratio of defatted soybeans to Aspergillus oryzae koji = 1:0.00015 and add koji, and stir thoroughly;

[0110] 3. Add Aspergillus oryzae and spread the defatted soybeans evenly in the fermentation equipment, keeping the average thickness no more than 3cm, put them into the fermentation cabinet, control the temperature at 32℃ to start fermentation, and the total fermentation time is 38h. Take out the fermentation equipment 16h after the start of fermentation, stir the fermented material thoroughly and evenly, then put it into the fermentation cabinet to continue fermenting at 27℃ for 7h, take it out for the second stirring; then continue to ferment at 27℃ for 5h, take it out for the third stirring, and then ferment at 26℃ until the end;

[0111] 4. After fermentation is completed, add 60°C drinking water 2.5 times the total mass of the fermented material, transfer to a clean conical flask and stir for 5 minutes, then use a high-speed shearing machine at a speed of 12000r / min for 5 minutes until the material becomes a uniform slurry to obtain a ground slurry;

[0112] 5. Place the ground slurry in a centrifuge and centrifuge at 10,000 r / min and 24°C for 15 minutes. Then take the supernatant and filter it through a 200-mesh filter cloth. Then place it in a vacuum rotary evaporator and concentrate it in a water bath at 60°C and -0.08MPa vacuum to a solid content of 35%, which is the finished product.

[0113] In this comparative example, the defatted soybeans used had a protein content of 47%, a moisture content of 11%, an ash content of 5.8%, and a crude fat content of 1.1%.

[0114] Comparative Example 3

[0115] The method is similar to that of Example 1, except that the defatted soybean processing step in step 1 of Comparative Example 3 is only for soaking without subsequent steaming, and the remaining steps are the same as those of Example 1.

[0116] In this comparative example, the defatted soybeans used had a protein content of 47%, a moisture content of 11%, an ash content of 5.8%, and a crude fat content of 1.1%.

[0117] Comparative Example 4

[0118] The method is similar to that of Example 1, except that, in Comparative Example 4, 0.0075% of the total mass of defatted soybeans was replaced by 0.015% of Aspergillus oryzae by 0.0075% of the total mass of defatted soybeans by Lactobacillus plantarum and 0.075% of the total mass of defatted soybeans by Streptococcus thermophilus, and the culture conditions were anaerobic environment at 40° C. for 48 h, and the remaining steps were the same as those of Example 1.

[0119] Comparative Example 5

[0120] The method is similar to that of Example 1, except that acidic protease is used in place of composite protease in Comparative Example 5, the pH of the slurry is adjusted to 3.5 with 1 mol / L hydrochloric acid solution before adding the protease, the enzymolysis temperature is 45°C, and the remaining steps are the same as those of Example 1.

[0121] Comparative Example 6

[0122] The method is similar to that of Example 1, except that papain is used in place of the composite protease in Comparative Example 6, and the remaining steps are the same as those of Example 1.

[0123] Comparative Example 7

[0124] The method is similar to that of Example 1, except that the composite protease in Comparative Example 7 is papain and acid protease, the mass ratio of papain to acid protease is 2:1, and the remaining steps are the same as those of Example 1.

[0125] Comparative Example 8

[0126] The method is similar to that of Example 1, except that the composite protease in Comparative Example 8 is papain and high-temperature neutral protease, the mass ratio of papain to high-temperature neutral protease is 1:2, and the remaining steps are the same as those of Example 1.

[0127] Test examples, sensory tests

[0128] The effects of the samples in the embodiments were tested by adding them to a white vinegar, an aged vinegar, a rice vinegar and a lemon claw snack food to test the sour stimulation, sour burning sensation, sour mellowness, mellowness and other aspects of the products, in order to verify the inhibitory effect of the soybean flavor peptide of the present application on the sour stimulation in food.

[0129] In test experiment 1, the white vinegar sample used is a commercially available product, and its ingredients are: water, edible alcohol, edible salt, edible acetic acid, sodium benzoate. The total acidity of the white vinegar sample is ≥10g / 100mL.

[0130] In test experiment 1, the aged vinegar used was a commercial product, and its ingredients were: water, sorghum, wheat bran, rice, wheat, barley, peas, and edible salt. The total acidity of the aged vinegar sample was ≥6g / 100mL.

[0131] In test experiment 1, the rice vinegar used was a commercial product, and its ingredients were: water, rice, and white sugar. The total acidity of the rice vinegar sample was ≥5g / 100mL.

[0132] In the second test, the lemon chicken feet used is a commercial product, and its ingredients are: chicken feet, water, chili, garlic, white sugar, vinegar, salt, soybean oil, chili oil, Sichuan pepper oil, chicken seasoning, lemon, monosodium glutamate, white wine, citric acid, sodium diacetate, sodium dehydroacetate, sodium D-isoascorbate, potassium sorbate, nisin, sodium tripolyphosphate, edible flavors and spices. Among them, the total acid of the vinegar used is ≥5g / 100mL, and the amount of lemon juice added is ≥5%.

[0133] Effect test experiment 1:

[0134] The soybean flavor peptide examples (Examples 1-4) and comparative examples (Comparative Examples 1-8) described in this application were added to the white vinegar, aged vinegar, and rice vinegar samples at 0.05% and 0.1% respectively. After stirring evenly, a sensory test was performed to score the samples from five dimensions: sour stimulation, sour burning, sour cotton softness, sour mellowness, and overall preference. The scores were 1 to 7 points. The higher the score, the more obvious the description (such as 1 point for no, 4 points for, and 7 points for very obvious). A total of 17 people participated in the test, and the following score is the average score of the samples.

[0135] The application results of the white vinegar sample and the product of Example 1 are shown in Table 1.

[0136] Table 1

[0137]

[0138] The application results of the white vinegar sample and the product of Example 2 are shown in Table 2.

[0139] Table 2

[0140]

[0141] The application results of the white vinegar sample and the product of Example 3 are shown in Table 3.

[0142] Table 3

[0143]

[0144] The application results of the white vinegar sample and the product of Example 4 are shown in Table 4.

[0145] Table 4

[0146]

[0147] The application results of the white vinegar sample and the product of Comparative Example 1 are shown in Table 5.

[0148] Table 5

[0149]

[0150] The application results of the white vinegar sample and the product of Comparative Example 2 are shown in Table 6.

[0151] Table 6

[0152]

[0153] The product application results of the white vinegar sample and Comparative Example 3 are shown in Table 7.

[0154] Table 7

[0155]

[0156] The product application results of the white vinegar sample and Comparative Example 4 are shown in Table 8.

[0157] Table 8

[0158]

[0159] The application results of the white vinegar sample and the product of Comparative Example 5 are shown in Table 9.

[0160] Table 9

[0161]

[0162] The application results of the white vinegar sample and the product of Comparative Example 6 are shown in Table 10.

[0163] Table 10

[0164]

[0165] The application results of the white vinegar sample and the product of Comparative Example 7 are shown in Table 11.

[0166] Table 11

[0167]

[0168] The product application results of the white vinegar sample and Comparative Example 8 are shown in Table 12.

[0169] Table 12

[0170]

[0171] The product application results of aged vinegar and Example 1 are shown in Table 13.

[0172] Table 13

[0173]

[0174] The product application results of aged vinegar and Example 2 are shown in Table 14.

[0175] Table 14

[0176]

[0177] The product application results of aged vinegar and Example 3 are shown in Table 15.

[0178] Table 15

[0179]

[0180] The product application results of aged vinegar and Example 4 are shown in Table 16.

[0181] Table 16

[0182]

[0183] The product application results of aged vinegar and comparative example 1 are shown in Table 17.

[0184] Table 17

[0185]

[0186] The product application results of aged vinegar and comparative example 2 are shown in Table 18.

[0187] Table 18

[0188]

[0189] The product application results of aged vinegar and comparative example 3 are shown in Table 19.

[0190] Table 19

[0191]

[0192] The product application results of aged vinegar and comparative example 4 are shown in Table 20.

[0193] Table 20

[0194]

[0195] The product application results of aged vinegar and comparative example 5 are shown in Table 21.

[0196] Table 21

[0197]

[0198] The product application results of aged vinegar and comparative example 6 are shown in Table 22.

[0199] Table 22

[0200]

[0201] The product application results of aged vinegar and comparative example 7 are shown in Table 23.

[0202] Table 23

[0203]

[0204] The product application results of aged vinegar and comparative example 8 are shown in Table 24.

[0205] Table 24

[0206]

[0207] The product application results of rice vinegar and Example 1 are shown in Table 25.

[0208] Table 25

[0209]

[0210] The product application results of rice vinegar and Example 2 are shown in Table 26.

[0211] Table 26

[0212]

[0213] The product application results of rice vinegar and Example 3 are shown in Table 27.

[0214] Table 27

[0215]

[0216] The product application results of rice vinegar and Example 4 are shown in Table 28.

[0217] Table 28

[0218]

[0219] The product application results of rice vinegar and Comparative Example 1 are shown in Table 29.

[0220] Table 29

[0221]

[0222] The product application results of rice vinegar and Comparative Example 2 are shown in Table 30.

[0223] Table 30

[0224]

[0225] The product application results of rice vinegar and Comparative Example 3 are shown in Table 31.

[0226] Table 31

[0227]

[0228] The product application results of rice vinegar and Comparative Example 4 are shown in Table 32.

[0229] Table 32

[0230]

[0231] The product application results of rice vinegar and Comparative Example 5 are shown in Table 33.

[0232] Table 33

[0233]

[0234] The product application results of rice vinegar and Comparative Example 6 are shown in Table 34.

[0235] Table 34

[0236]

[0237] The product application results of rice vinegar and Comparative Example 7 are shown in Table 35.

[0238] Table 35

[0239]

[0240] The product application results of rice vinegar and Comparative Example 8 are shown in Table 36.

[0241] Table 36

[0242]

[0243] Effect test experiment 2:

[0244] The application of the lemon chicken feet and the products of Examples 1 to 4 and Comparative Examples 1 to 8 is as follows:

[0245] Experimental materials: chicken feet, water, soy sauce, chili, garlic, green onion, white sugar, vinegar (white vinegar), table salt, soybean oil, chili oil, Sichuan pepper oil, chicken seasoning, lemon, MSG, citric acid, sodium D-isoascorbate, potassium sorbate, and edible flavors and spices.

[0246] Thaw the purchased frozen chicken feet, clean them, cut the nails and cut them into appropriate sizes. Add cold water to the pot, add appropriate amount of ginger slices, scallion segments, salt, and cooking wine, and blanch for 5 minutes. Take out the chicken feet, drain the water and let cool to room temperature. According to the formula ratio, add chili grains, garlic grains, vinegar, lemon juice and other seasonings and food additives to prepare the seasoning sauce. To marinate 500g chicken feet, you need about: 50g soy sauce, 10g chili grains, 20g garlic, 20g white sugar, 5g salt, 3g chicken seasoning, 2g soybean oil, 2g chili oil, 1g pepper oil, 1g MSG, and food additives according to the limit standard and actual needs. The amount of vinegar added is 5g / 100g finished product, and the amount of lemon juice added is 6% finished product. The soybean flavor peptide samples produced in Examples 1 to 4 and Comparative Examples 1 to 8 were added to the seasoning juice in proportion, and the treated chicken feet were added. After stirring evenly, the mixture was refrigerated and marinated at 4° C. for 12 hours, and the chicken feet were taken out for sensory testing:

[0247] The application results of lemon chicken feet and the product of Example 1 are shown in Table 37.

[0248] Table 37

[0249]

[0250] The application results of lemon chicken feet and the product of Example 2 are shown in Table 38.

[0251] Table 38

[0252]

[0253] The application results of lemon chicken feet and the product of Example 3 are shown in Table 39.

[0254] Table 39

[0255]

[0256] The application results of lemon chicken feet and the products of Example 4 are shown in Table 40.

[0257] Table 40

[0258]

[0259]

[0260] The application results of lemon chicken feet and the product of comparative example 1 are shown in Table 41.

[0261] Table 41

[0262]

[0263] The application results of lemon chicken feet and the product of comparative example 2 are shown in Table 42.

[0264] Table 42

[0265]

[0266] The product application results of lemon chicken feet and comparative example 3 are shown in Table 43.

[0267] Table 43

[0268]

[0269] The product application results of lemon chicken feet and comparative example 4 are shown in Table 44.

[0270] Table 44

[0271]

[0272] The product application results of lemon chicken feet and comparative example 5 are shown in Table 45.

[0273] Table 45

[0274]

[0275] The product application results of lemon chicken feet and comparative example 6 are shown in Table 46.

[0276] Table 46

[0277]

[0278] The product application results of lemon chicken feet and comparative example 7 are shown in Table 47.

[0279] Table 47

[0280]

[0281] The product application results of lemon chicken feet and comparative example 8 are shown in Table 48.

[0282] Table 48

[0283]

[0284] The effect of adding 0.05% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to white vinegar is as follows: Figure 1 shown.

[0285] The effect of adding 0.1% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to white vinegar is as follows: Figure 2 shown.

[0286] The effect of adding 0.05% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to the aged vinegar is as follows: Figure 3 shown.

[0287] The effect of adding 0.1% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to the aged vinegar is as follows: Figure 4 shown.

[0288] The effect of adding 0.05% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to rice vinegar is as follows: Figure 5 shown.

[0289] The effect of adding 0.1% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to rice vinegar is as follows: Figure 6 shown.

[0290] The effect of adding 0.3% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to lemon chicken feet is as follows: Figure 7 shown.

[0291] The effect of adding 0.5% of the products of Examples 1 to 4 and Comparative Examples 1 to 8 to lemon chicken feet is as follows: Figure 8 shown.

[0292] In addition, the peptide content (desalted dry basis) and the proportion of 200-1000 Da molecular weight peptide segments in the products of Examples 1-4 and Comparative Examples 1-8 are shown in Table 49.

[0293] Table 49

[0294] Group Desalted dry basis peptide content % 200~1000Da molecular weight peptide segment percentage Example 1 35.4 41.7 Example 2 37.3 43.5 Example 3 36.8 43.9 Example 4 34.8 41.1 Comparative Example 1 15.7 27.3 Comparative Example 2 23.6 31.2 Comparative Example 3 27.1 34.2 Comparative Example 4 26.6 30.5 Comparative Example 5 27.4 28.4 Comparative Example 6 26.9 27.5 Comparative Example 7 27.2 27.8 Comparative Example 8 29.0 30.5

[0295] The peptide content of the products of Examples 1 to 4 and Comparative Examples 1 to 8 (desalted dry basis) is 200 to 1000 Da molecular weight peptides accounted for Fig. 9 shown.

[0296] This application uses defatted soybeans as the main raw material, inoculates Aspergillus oryzae for fermentation, adds a composite protease for directed enzymatic hydrolysis, and uses spray drying as the powder making process. Its main function is that Aspergillus oryzae protease is metabolized during the fermentation of Aspergillus oryzae, and the soybean protein is directed enzymatically hydrolyzed under specific conditions with the addition of papain and neutral protease to obtain a soybean flavor peptide product rich in small molecule flavor peptides.

[0297] The soybean flavor peptide produced in the present application has a desalted dry protein content of more than 60%, and a desalted dry peptide content of ≥35%, wherein the peptide molecule distribution is mainly 200 to 1000 Daltons, accounting for more than 40%.

[0298] The soybean flavor peptide produced in this application is tested for application in various types of vinegar and foods with sour taste as the main flavor, such as lemon chicken feet. It has a significant inhibitory effect on the sour stimulation of the product and the burning sensation of the sour taste on the esophagus, making the sour taste of the product softer and more mellow, and improving the comfort of the sour taste in the mouth.

[0299] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application rather than to limit the scope of protection of the present application. Although the present application has been described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the present application can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present application.

Claims

1. A method for preparing soybean flavor peptide, characterized in that: The following steps are involved: S1. Fully mixing the steamed soybeans / defatted soybeans and Aspergillus oryzae, and fermenting them to obtain a fermented product; S2, adding water to the fermented product, stirring and shearing, to obtain a slurry; S3, mixing the ground material and the composite protease for enzymolysis to obtain an enzymolysis solution, inactivating the enzyme, centrifuging the inactivated enzymolysis solution, filtering the supernatant, and concentrating it into a solid to obtain soybean flavor peptides; The composite protease comprises papain and neutral protease.

2. The method for preparing soybean flavor peptide according to claim 1, characterized in that: The mass ratio of papain to neutral protease is 1:(2-5).

3. The method for preparing soybean flavor peptide according to claim 1, characterized in that: In the step S1, the mass ratio of the cooked soybeans / defatted soybeans to Aspergillus oryzae is 1:(0.00015-0.00025).

4. The method for preparing soybean flavor peptide according to claim 1, characterized in that: In step S1, the fermentation step includes: The soybeans / defatted soybeans are fully stirred at 16-17h, 23-24h, and 28-29h after the start of fermentation. The temperature of the soybeans / defatted soybeans is maintained at 32-35°C from the start of fermentation to the first stirring, 27-32°C from the first stirring to the second stirring, 27-32°C from the second stirring to the third stirring, and 26-29°C from the third stirring to the completion of fermentation.

5. The method for preparing soybean flavor peptide according to claim 1, characterized in that: In the step S2, the weight ratio of the fermented product to water is 1:(2-2.5).

6. The method for preparing soybean flavor peptide according to claim 1, characterized in that: In step S2, the water temperature is 55-65°C and the stirring time is 5-8 minutes; The shearing speed is 12000-15000 r / min, and the shearing time is 5-10 min.

7. The method for preparing soybean flavor peptide according to claim 1, characterized in that: In the step S3, the inoculation amount of the composite protease is 1.5-2.0%.

8. The method for preparing soybean flavor peptide according to claim 1, characterized in that: In step S3, the centrifugal speed is 8000-11000 r / min, the centrifugal temperature is 24-25° C., and the centrifugal time is 10-20 min; The concentration temperature is 58 to 65°C, the concentration pressure is -0.1 to -0.08 MPa, and the concentration time is 10 to 20 minutes.

9. The soybean flavor peptide prepared by the method for preparing soybean flavor peptide according to any one of claims 1 to 8, characterized in that: Among the soybean flavor peptides, small molecule peptides with a molecular weight of 200 to 1000 Da account for more than 40%.

10. Use of the soybean flavor peptide according to claim 9 in inhibiting the acid stimulation of food.

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