阅读说明：本技术 一种利用红薯生产γ-氨基丁酸的方法 (Method for producing gamma-aminobutyric acid from sweet potatoes ) 是由 江世文 王红梅 于 2020-12-18 设计创作，主要内容包括：本发明公开了一种利用红薯生产γ-氨基丁酸的方法,包括以下步骤：(1)将新鲜红薯进行初加工提取湿红薯粉；(2)在湿红薯粉中加入相当于红薯粉重量0.5％～1.5％的α-淀粉酶,加热到35～45℃,糊化45～90分钟,用碳酸钾中和至pH为4.0～5.5,得到红薯稀浆糖液；(3)在红薯稀浆糖液中加入培养基组分,混合均匀,调节pH至6.0～6.8,得到发酵培养基；(4)接种乳酸乳球菌,在30～45℃下发酵培养48～120小时；(5)过滤去渣脱色,滤液经提纯浓缩干燥,制得γ-氨基丁酸。本发明利用红薯作为发酵培养基的主要原材料,降低了生产成本,制得的γ-氨基丁酸安全可靠,可广泛应用于食品与医药行业。(The invention discloses a method for producing gamma-aminobutyric acid by sweet potatoes, which comprises the following steps: (1) carrying out primary processing on fresh sweet potatoes to extract wet sweet potato powder; (2) adding alpha-amylase which is 0.5-1.5% of the weight of the sweet potato powder into the wet sweet potato powder, heating to 35-45 ℃, gelatinizing for 45-90 minutes, and neutralizing with potassium carbonate until the pH value is 4.0-5.5 to obtain sweet potato slurry sugar liquor; (3) adding the culture medium components into the sweet potato slurry sugar liquor, uniformly mixing, and adjusting the pH to 6.0-6.8 to obtain a fermentation culture medium; (4) inoculating lactococcus lactis, and fermenting and culturing at 30-45 ℃ for 48-120 hours; (5) filtering, removing residue, decolorizing, purifying, concentrating, and drying the filtrate to obtain gamma-aminobutyric acid. The invention uses sweet potato as the main raw material of the fermentation medium, reduces the production cost, and the prepared gamma-aminobutyric acid is safe and reliable and can be widely applied to the food and medicine industries.)

1. A method for producing gamma-aminobutyric acid by sweet potatoes is characterized by comprising the following steps:

(1) carrying out primary processing on fresh sweet potatoes to extract wet sweet potato powder;

(2) adding alpha-amylase which is 0.5-1.5% of the weight of the sweet potato powder into the wet sweet potato powder, heating to 35-45 ℃, gelatinizing for 45-90 minutes, and neutralizing with potassium carbonate until the pH value is 4.0-5.5 to obtain sweet potato slurry sugar liquor;

(3) adding culture medium components into the sweet potato slurry sugar solution, wherein the components are calculated by dry substances according to the following mass percent: 2.0-8.0% of sweet potato thin pulp sugar liquor, 0.2-5.0% of yeast production waste liquid, 0.1-0.5% of monopotassium phosphate, 0.05-0.4% of magnesium sulfate heptahydrate, 0.05-0.4% of ammonium citrate, 0.01-0.05% of sodium chloride, 0.01-0.05% of ammonium acetate, 0.001-0.006% of ferrous sulfate, 0.001-0.009% of manganese sulfate, 0.001-0.008% of pyridoxal phosphate, 0.05-0.2% of coconut oil oleic acid defoaming agent, 0.02-0.25% of tween 80 and the balance of deionized water, uniformly mixing, and adjusting the pH to 6.0-6.8 to obtain a fermentation culture medium;

(4) inoculating lactococcus lactis, and fermenting and culturing at 30-45 ℃ for 48-120 hours;

(5) filtering, removing residue, decolorizing, purifying, concentrating, and drying the filtrate to obtain gamma-aminobutyric acid.

2. The method for producing gamma-aminobutyric acid from sweet potatoes as claimed in claim 1, wherein the step (1) is to perform preliminary processing on fresh sweet potatoes sequentially through the following steps: cleaning, crushing, grinding into thick liquid, stirring, filtering, removing sand and collecting.

3. The method for producing gamma-aminobutyric acid from sweet potatoes according to claim 1, wherein the alpha-amylase added to the wet sweet potato powder in the step (2) is 1.0% of the weight of the sweet potato powder.

4. The method for producing gamma-aminobutyric acid from sweet potatoes as claimed in claim 1, wherein the heating temperature in the step (2) is 40-42 ℃, and the gelatinization time is 60 minutes.

5. The method for producing gamma-aminobutyric acid from sweet potatoes according to claim 1, wherein the step (2) is performed by neutralizing with potassium carbonate until the pH value is 4.6-4.8.

6. The method for producing gamma-aminobutyric acid from sweet potatoes according to claim 1, wherein the mass percentage of each component in the step (3) is as follows on a dry matter basis: 3.5% of sweet potato thin pulp sugar liquor, 2.0% of yeast production waste liquid, 0.25% of potassium dihydrogen phosphate, 0.2% of magnesium sulfate heptahydrate, 0.15% of ammonium citrate, 0.03% of sodium chloride, 0.03% of ammonium acetate, 0.002% of ferrous sulfate, 0.002% of manganese sulfate, 0.002% of pyridoxal phosphate, 0.15% of coconut oil oleic acid defoaming agent, 0.1% of tween 80 and the balance of deionized water.

7. The method for producing gamma-aminobutyric acid from sweet potatoes according to claim 1, wherein the step (3) is performed by adjusting pH to 6.3.

8. The method for producing gamma-aminobutyric acid from sweet potatoes according to claim 1, wherein the fermentation and culture process of the step (4) is as follows: fermenting and culturing for 72 hours at 35-36 ℃.

Technical Field

The invention belongs to the technical field of preparation of gamma-aminobutyric acid, and particularly relates to a method for producing gamma-aminobutyric acid by sweet potatoes.

Background

Gamma-aminobutyric acid (GABA) also known as 4-aminobutyric acid (GABA), and its molecular formula is NH₂CH₂CH₂CH₂COOH, molecular weight 103.1. Is a non-protein amino acid naturally existing in various biological cells and body fluids, is not a hormone, and is widely applied to the fields of medicines, foods, fertilizers, feeds and the like. At present, the methodAmong the natural biostimulants registered in the united states, the active ingredient contains GABA, which is currently recognized as a plant anti-adversity stimulant.

The GABA synthesis method comprises a chemical synthesis method and a biological fermentation method, the chemical synthesis method needs strong corrosive solvents such as strong acid or strong alkali, the reaction condition is severe, the toxicity of raw materials is high, the production cost is high, for example, a product with the content of the y-aminobutyric acid of 20% is prepared, the production cost is about 5 ten thousand yuan/ton, but the method cannot be used in the fields of food, medicine and the like because harmful residues exist in organic synthesis and the like, and only can be used as a chemical raw material. In actual industrial production, GABA is mainly produced by a biological fermentation method.

The biological fermentation method comprises the traditional microbial fermentation method and the microbial conversion method, wherein the GABA is produced in the early stage mainly by a direct fermentation method, escherichia coli, lactobacillus plantarum and the like are taken as production bacteria, the L-glutamic acid in fermentation liquor is converted into the GABA by utilizing the action of glutamate decarboxylase in bacteria, and the GABA is prepared by separating and purifying the fermentation liquor. The traditional fermentation method has expensive culture medium, needs expensive raw materials such as peptone, glucose, L-sodium glutamate and refined milk powder, and has high production cost all the time.

Disclosure of Invention

Aiming at the defects or improvement requirements of the prior art, the invention aims at providing the preparation method of the gamma-aminobutyric acid, which has the advantages of high quality, low price, simple process, convenient operation, low production cost, less environmental pollution and safe eating.

In order to realize the aim, the invention provides a method for producing gamma-aminobutyric acid by sweet potatoes, which comprises the following steps:

(1) carrying out primary processing on fresh sweet potatoes to extract wet sweet potato powder;

(2) adding alpha-amylase which is 0.5-1.5% of the weight of the sweet potato powder into the wet sweet potato powder, heating to 35-45 ℃, gelatinizing for 45-90 minutes, and neutralizing with potassium carbonate until the pH value is 4.0-5.5 to obtain sweet potato slurry sugar liquor;

(3) adding culture medium components into the sweet potato slurry sugar solution, wherein the components are calculated by dry substances according to the following mass percent: 2.0-8.0% of sweet potato thin pulp sugar liquor, 0.2-5.0% of yeast production waste liquid, 0.1-0.5% of monopotassium phosphate, 0.05-0.4% of magnesium sulfate heptahydrate, 0.05-0.4% of ammonium citrate, 0.01-0.05% of sodium chloride, 0.01-0.05% of ammonium acetate, 0.001-0.006% of ferrous sulfate, 0.001-0.009% of manganese sulfate, 0.001-0.008% of pyridoxal phosphate, 0.05-0.2% of coconut oil oleic acid defoaming agent, 0.02-0.25% of tween 80 and the balance of deionized water, uniformly mixing, and adjusting the pH to 6.0-6.8 to obtain a fermentation culture medium;

(4) inoculating lactococcus lactis, and fermenting and culturing at 30-45 ℃ for 48-120 hours;

(5) filtering, removing residue, decolorizing, purifying, concentrating, and drying the filtrate to obtain gamma-aminobutyric acid.

Further, the fresh sweet potatoes are subjected to primary processing in the step (1) and sequentially subjected to the following steps: cleaning, crushing, grinding into thick liquid, stirring, filtering, removing sand and collecting.

Further, the alpha-amylase added into the wet sweet potato powder in the step (2) is equivalent to 1.0 percent of the weight of the sweet potato powder.

Further, the heating temperature in the step (2) is 40-42 ℃, and the gelatinization time is 60 minutes.

Further, neutralizing the solution obtained in the step (2) with potassium carbonate until the pH value is 4.6-4.8.

Further, the components in the step (3) comprise the following components in percentage by mass on a dry basis: 3.5% of sweet potato thin pulp sugar liquor, 2.0% of yeast production waste liquid, 0.25% of potassium dihydrogen phosphate, 0.2% of magnesium sulfate heptahydrate, 0.15% of ammonium citrate, 0.03% of sodium chloride, 0.03% of ammonium acetate, 0.002% of ferrous sulfate, 0.002% of manganese sulfate, 0.002% of pyridoxal phosphate, 0.15% of coconut oil oleic acid defoaming agent, 0.1% of tween 80 and the balance of deionized water.

Further, the pH is adjusted to 6.3 in the step (3).

Further, the fermentation culture process in the step (4) is as follows: fermenting and culturing for 72 hours at 35-36 ℃.

The waste liquid produced by the yeast is the waste liquid discharged after being separated by a separator in the molasses fermentation process in the yeast manufacturing industry, more than 5 million tons of waste liquid are produced in one production line year, and the waste liquid belongs to the environmental protection treatment problem, can be obtained freely, is rich in active saccharomycetes and fulvic acid, and has the solid organic matter content of more than 50 percent.

Lactococcus lactis (Lactococcus lactis) used in the invention is a known common commodity sold in the market, and the strain is deposited in the food science research laboratory of south China university with the deposit number of SYFS 1.009.

The invention has the beneficial effects that: the sweet potato is used as a main raw material of the fermentation medium, so that the production cost is reduced; the waste liquid in the yeast manufacturing industry is utilized, so that the comprehensive utilization of waste resources is realized, and the problem of environmental protection treatment is solved; the conversion rate is higher through the mixed fermentation of the active saccharomycetes and the lactococcus lactis in the yeast production waste liquid. The gamma-aminobutyric acid prepared by the method is safe and reliable, and can be widely applied to the food and medicine industries.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

A method for producing gamma-aminobutyric acid by sweet potatoes comprises the following steps:

(1) fresh sweet potatoes are sequentially subjected to the working procedures of cleaning, crushing, grinding, stirring, filtering, sand removing and collecting, and wet sweet potato powder is primarily processed and extracted. The preliminary processing adopts equipment comprising a squirrel-cage potato washing machine, an automatic feeding potato washing machine, a sweet potato crusher, a pulping separator, a starch slurry stirrer, a fine filter, a sand remover and a collecting tank.

(2) Adding alpha-amylase which is 0.5 percent of the weight of the sweet potato powder into the wet sweet potato powder, heating to 45 ℃, gelatinizing for 90 minutes, and neutralizing with potassium carbonate until the pH value is 4.0 to obtain sweet potato slurry sugar liquid.

(3) Adding culture medium components into the sweet potato slurry sugar solution, wherein the components are calculated by dry substances according to the following mass percent: 2.0% of sweet potato thin pulp sugar liquor, 0.2% of yeast production waste liquid, 0.1% of monopotassium phosphate, 0.05% of magnesium sulfate heptahydrate, 0.05% of ammonium citrate, 0.01% of sodium chloride, 0.01% of ammonium acetate, 0.001% of ferrous sulfate, 0.001% of manganese sulfate, 0.001% of pyridoxal phosphate, 0.05% of coconut oil oleic acid defoaming agent, 0.02% of tween 80 and the balance of deionized water, uniformly mixing, and adjusting the pH to 6.0 to obtain the fermentation medium.

(4) Lactococcus lactis (Lactococcus lactis) SYFS 1.009 was inoculated, and fermentation-cultured at 30 ℃ for 120 hours.

(5) Filtering, removing residue, decolorizing, purifying, concentrating, and drying the filtrate to obtain gamma-aminobutyric acid.

Example 2

A method for producing gamma-aminobutyric acid by sweet potatoes comprises the following steps:

(1) fresh sweet potatoes are sequentially subjected to the working procedures of cleaning, crushing, grinding, stirring, filtering, sand removing and collecting, and wet sweet potato powder is primarily processed and extracted. The preliminary processing adopts equipment comprising a squirrel-cage potato washing machine, an automatic feeding potato washing machine, a sweet potato crusher, a pulping separator, a starch slurry stirrer, a fine filter, a sand remover and a collecting tank.

(2) Adding alpha-amylase which is 1.5 percent of the weight of the sweet potato powder into the wet sweet potato powder, heating to 35 ℃, gelatinizing for 45 minutes, and neutralizing with potassium carbonate until the pH value is 5.5 to obtain sweet potato slurry sugar liquid.

(3) Adding culture medium components into the sweet potato slurry sugar solution, wherein the culture medium components comprise the following dry substances in percentage by mass: 8.0% of sweet potato thin pulp sugar liquor, 5.0% of yeast production waste liquid, 0.5% of potassium dihydrogen phosphate, 0.4% of magnesium sulfate heptahydrate, 0.4% of ammonium citrate, 0.05% of sodium chloride, 0.05% of ammonium acetate, 0.006% of ferrous sulfate, 0.009% of manganese sulfate, 0.008% of pyridoxal phosphate, 0.2% of coconut oil oleic acid defoaming agent, 0.25% of tween 80 and the balance of deionized water, uniformly mixing, and adjusting the pH to 6.8 to obtain the fermentation medium.

(4) Lactococcus lactis (Lactococcus lactis) SYFS 1.009 was inoculated, and fermentation-cultured at 45 ℃ for 48 hours.

(5) Filtering, removing residue, decolorizing, purifying, concentrating, and drying the filtrate to obtain gamma-aminobutyric acid.

Example 3

A method for producing gamma-aminobutyric acid by sweet potatoes comprises the following steps:

(1) fresh sweet potatoes are sequentially subjected to the working procedures of cleaning, crushing, grinding, stirring, filtering, sand removing and collecting, and wet sweet potato powder is primarily processed and extracted. The preliminary processing adopts equipment comprising a squirrel-cage potato washing machine, an automatic feeding potato washing machine, a sweet potato crusher, a pulping separator, a starch slurry stirrer, a fine filter, a sand remover and a collecting tank.

(2) Adding alpha-amylase which is 1.0 percent of the weight of the sweet potato powder into the wet sweet potato powder, heating to 40 ℃, gelatinizing for 60 minutes, and neutralizing with potassium carbonate until the pH value is 4.6 to obtain sweet potato slurry sugar liquid.

(3) Adding culture medium components into the sweet potato slurry sugar solution, wherein the culture medium components comprise the following dry substances in percentage by mass: 3.5% of sweet potato thin pulp sugar liquor, 2.0% of yeast production waste liquid, 0.25% of potassium dihydrogen phosphate, 0.2% of magnesium sulfate heptahydrate, 0.15% of ammonium citrate, 0.03% of sodium chloride, 0.03% of ammonium acetate, 0.002% of ferrous sulfate, 0.002% of manganese sulfate, 0.002% of pyridoxal phosphate, 0.15% of coconut oil oleic acid defoaming agent, 0.1% of tween 80 and the balance of deionized water are uniformly mixed, and the pH value is adjusted to 6.3 to obtain the fermentation medium.

(4) Inoculating Lactococcus lactis SYFS 1.009, fermenting and culturing at 35 deg.C for 72 hr.

(5) Filtering, removing residue, decolorizing, purifying, concentrating, and drying the filtrate to obtain gamma-aminobutyric acid.

Example 4

A method for producing gamma-aminobutyric acid by sweet potatoes comprises the following steps:

(1) fresh sweet potatoes are sequentially subjected to the working procedures of cleaning, crushing, grinding, stirring, filtering, sand removing and collecting, and wet sweet potato powder is primarily processed and extracted. The preliminary processing adopts equipment comprising a squirrel-cage potato washing machine, an automatic feeding potato washing machine, a sweet potato crusher, a pulping separator, a starch slurry stirrer, a fine filter, a sand remover and a collecting tank.

(2) Adding alpha-amylase which is 1.0 percent of the weight of the sweet potato powder into the wet sweet potato powder, heating to 42 ℃, gelatinizing for 60 minutes, and neutralizing with potassium carbonate until the pH value is 4.8 to obtain sweet potato slurry sugar liquid.

(3) Adding culture medium components into the sweet potato slurry sugar solution, wherein the culture medium components comprise the following dry substances in percentage by mass: 3.5% of sweet potato thin pulp sugar liquor, 2.0% of yeast production waste liquid, 0.25% of potassium dihydrogen phosphate, 0.2% of magnesium sulfate heptahydrate, 0.15% of ammonium citrate, 0.03% of sodium chloride, 0.03% of ammonium acetate, 0.002% of ferrous sulfate, 0.002% of manganese sulfate, 0.002% of pyridoxal phosphate, 0.15% of coconut oil oleic acid defoaming agent, 0.1% of tween 80 and the balance of deionized water are uniformly mixed, and the pH value is adjusted to 6.3 to obtain the fermentation medium.

(4) Inoculating Lactococcus lactis SYFS 1.009, fermenting and culturing at 36 deg.C for 72 hr.

(5) Filtering, removing residue, decolorizing, purifying, concentrating, and drying the filtrate to obtain gamma-aminobutyric acid.

Through detection, the yield of the gamma-aminobutyric acid in the concentrated solution obtained by fermentation culture for 72 hours in the examples 3 and 4 can reach 335.0g/L, and the molar conversion rate of the sweet potato powder reaches 58.9%.

The above-mentioned embodiments only express the embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.