High histidine-containing rice fermentation liquor, preparation method and application thereof

Abstract

The present application relates to a kind of high histidine rice fermentation liquor and its preparation method and application. Wherein, the rice fermentation liquor is prepared by rice culture medium first through enzymolysis, then sequentially through yeast fermentation, lactic acid bacteria fermentation;After enzymolysis, the content of histidine in the rice fermentation liquor after fermentation is significantly improved, and contains a variety of flavor substances.In addition, the rice fermentation liquor of the present application can be prepared into various forms of rice fermented food, used in medicine, health food or infant food field, has great economic value.

Description

Technical Field

[0001] This invention relates to the field of bio-fermentation technology, and in particular to a rice fermentation broth with high histidine content, its preparation method, and its application. Background Technology

[0002] Histidine is an α-amino acid with the chemical formula C6H9N3O2 and a molecular weight of 155. It was first isolated in 1896 by the German physicist Ebrich Kossel. Because adults can synthesize histidine from common intermediate metabolites, L-histidine was initially considered a non-essential amino acid. However, further research revealed that infants' histidine synthesis levels are insufficient to meet their growth needs. In 2007, the WHO / FAO / UNU used various methods, including nitrogen balance and stable isotope studies, to investigate the requirements of essential amino acids, proposing the Estimated Average Requirement (EAR) of essential amino acids for humans. The histidine requirement is described in the table below:

[0003] Table 1 Estimated average histidine requirement for different age groups

[0004] Age / years 0.5～ 1～ 3～ 11～ 15～ 18～ Histidine average requirement (mg / (kg·d)) 22 15 12 12 11 10

[0005] As shown in the table above, infants aged 0-3 years have a significantly higher requirement for histidine than adults over three years old. Histidine is an essential amino acid for infants, but they cannot synthesize it themselves. Therefore, to ensure normal bodily function, a certain amount of histidine must be obtained daily from food. Furthermore, histidine is also an essential amino acid for patients with chronic uremia. Adding a small amount of histidine to their diet increases the rate at which the amino acid binds into hemoglobin, which can alleviate symptoms of renal anemia. Therefore, it is necessary to obtain a certain amount of histidine from food.

[0006] Rice is one of the world's three major staple foods, rich in nutrients. It contains approximately 75% carbohydrates (mainly starch), 7%–8% protein (primarily rice gluten, rice gum, and globulin), and 1.3%–1.8% fat, as well as small amounts of B vitamins and amino acids. Although rice is nutritionally rich, its flavor is monotonous and lacks distinctive characteristics; moreover, its histidine content is low, making it difficult to achieve health benefits and therapeutic effects. Therefore, improving the flavor while simultaneously increasing the histidine content during rice fermentation has significant economic value and application prospects. Summary of the Invention

[0007] The technical problem solved by this invention is that rice has a relatively simple flavor and a low histidine content, making it difficult to achieve health benefits and therapeutic effects. To address these issues, the purpose of this invention is to provide a high-histidine rice fermentation liquid, its preparation method, and its applications. The preparation method of this invention can significantly increase the histidine content while improving the flavor, and it can be prepared into various forms of rice fermentation products suitable for infants and young children, as well as patients with histidine deficiency.

[0008] Specifically, the present invention proposes the following technical solution:

[0009] On one hand, the present invention provides a rice fermentation broth with high histidine content, wherein the rice fermentation broth is obtained by first enzymatically hydrolyzing rice culture medium, and then successively fermenting it with yeast and lactic acid bacteria; wherein the mass percentage of histidine in the rice fermentation broth is above 0.09%.

[0010] In some embodiments, the mass percentage of histidine in the rice fermentation broth is 0.09% to 0.3%.

[0011] On the other hand, the present invention provides a method for preparing rice fermentation broth with high histidine content, characterized by comprising the following steps:

[0012] (1) Grind the rice into powder and sieve it to prepare rice culture medium;

[0013] (2) Add the first enzyme to the rice culture medium for the first enzymatic hydrolysis, then add the second enzyme for the second enzymatic hydrolysis, and finally obtain the enzymatic hydrolysate by enzyme inactivation treatment;

[0014] (3) Add yeast to the enzymatic hydrolysate obtained in step (2) to carry out the first fermentation step;

[0015] (4) Add carbon and nitrogen sources to the fermentation broth obtained in step (3), prepare culture medium, and then sterilize it;

[0016] (5) Inoculate lactic acid bacteria into the culture medium obtained in step (4) and carry out the second fermentation;

[0017] (6) Sterilize the fermentation liquid obtained in step (5) to obtain rice fermentation liquid.

[0018] In some implementations, in step (1), the rice is selected from one or more of glutinous rice, japonica rice, indica rice, white rice, red rice, purple rice, and black rice.

[0019] In some implementations, the rice has a mesh size of 80 to 200 mesh.

[0020] In some implementations, in step (1), the rice culture medium has a mass-volume percentage of 1% to 60%.

[0021] In some implementations, in step (1), the rice culture medium has a mass-volume percentage of 10% to 20%.

[0022] In some embodiments, in step (2), the first enzyme is selected from one or more of amylase, saccharifying enzyme and cellulase; preferably α-thermal amylase.

[0023] In some embodiments, in step (2), the mass-volume percentage of the first enzyme is 0.05% to 1% based on the volume of the rice culture medium obtained in step (1); preferably, the mass-volume percentage of the first enzyme is 0.1% to 0.4%.

[0024] In some implementations, in step (2), the enzymatic hydrolysis temperature of the first enzyme is 55–95°C; and / or the enzymatic hydrolysis time is 20–40 min.

[0025] In some embodiments, in step (2), the second enzyme is a protease; preferably papain;

[0026] In some embodiments, in step (2), the mass-volume percentage of the second enzyme is 0.01% to 1% based on the volume of the rice culture medium obtained in step (1); preferably, the mass-volume percentage of the second enzyme is 0.1% to 1%.

[0027] In some embodiments, in step (2), the mass-volume percentage of the second enzyme is 0.1% to 0.4%; or the mass-volume percentage of the second enzyme is 0.6% to 1%.

[0028] In some embodiments, in step (2), the enzymatic hydrolysis temperature of the second enzyme is 50-90°C, preferably 50-60°C; and / or the enzymatic hydrolysis time is 20-40 min.

[0029] In some embodiments, in step (3), the yeast mass-volume percentage is 0.01% to 4.5% based on the volume of the rice hydrolysate obtained in step (2); preferably, the yeast mass-volume percentage is 0.01% to 3%; more preferably, the yeast mass-volume percentage is 0.01% to 1%.

[0030] In some implementations, in step (3), the yeast is selected from one or more of Kluyveromyces, Saccharomyces cerevisiae, Pichia pastoris, Candida albicans, or Saccharomyces clausti.

[0031] In some embodiments, in step (3), the yeast is selected from Saccharomyces cerevisiae A3.12, Cyberlindnera fabianii C1.8, and / or Saccharomycopsis fibuligera d6.16.

[0032] In some embodiments, in step (3), the mass-volume percentage of *Saccharomyces cerevisiae* A3.12 is 0.01% to 1%, and / or the mass-volume percentage of *Cyberlindnera fabianii* C1.8 is 0.01% to 1%, and / or the mass-volume percentage of *Saccharomycopsis fibuligera* d6.16 is 0.01% to 1%, based on the volume of the rice hydrolysate obtained in step (2).

[0033] In some embodiments, in step (3), the mass-volume percentage of *Saccharomyces cerevisiae* A3.12 is 0.01% to 0.4% based on the volume of the rice hydrolysate obtained in step (2), and / or the mass-volume percentage of *Cyberlindnera fabianii* C1.8 is 0.01% to 0.4%, and / or the mass-volume percentage of *Saccharomycopsis fibuligera* d6.16 is 0.01% to 0.4%.

[0034] In some implementations, in step (3), the temperature of the first fermentation step is 28–40°C; and / or the fermentation time is 12–48 h.

[0035] In some implementations, in step (4), the carbon source is 1% to 5% of the total mass of the fermentation broth obtained in step (3).

[0036] In some implementations, in step (4), the carbon source is selected from one or more of glucose, fructose, sucrose and maltose, preferably glucose.

[0037] In some embodiments, in step (4), the mass fraction of the nitrogen source is 0.1% to 3% based on the mass of the fermentation broth obtained in step (3), preferably, the mass fraction of the nitrogen source is 0.1% to 1%.

[0038] In some implementations, in step (4), the nitrogen source is selected from one or more of hydrolyzed soybean protein, milk powder and yeast extract, preferably zinc-rich yeast extract.

[0039] In some embodiments, in step (5), the mass-volume percentage of lactic acid bacteria is 0.01% to 1% based on the volume of the culture medium obtained in step (4); preferably, the mass-volume percentage of lactic acid bacteria is 0.01% to 0.4%; more preferably, the mass-volume percentage of lactic acid bacteria is 0.1% to 0.4%.

[0040] In some implementations, in step (5), the lactic acid bacteria are selected from one or more of Pediococcus pentosaceus, Lactobacillus plantarum, Bifidobacterium longum, Bifidobacterium breve, Lactobacillus casei, Lactobacillus breve, Lactobacillus rhamnosus, and Lactobacillus acidophilus; preferably, the lactic acid bacteria are selected from Lactobacillus plantarum; more preferably, the lactic acid bacteria are selected from Lactobacillus plantarum RPC5.

[0041] In some implementations, the fermentation temperature in step (5) is 28–40°C, and / or the fermentation time is 12–48 h.

[0042] In some embodiments, the rice fermentation broth with high histidine content is prepared by the preparation method.

[0043] In some implementations, the rice fermentation liquid is used in the food industry.

[0044] In some embodiments, the rice fermentation broth with high histidine content is used in the preparation of pharmaceuticals, health foods, or infant foods.

[0045] In some implementations, the rice fermentation liquid is used in baked goods, puffed foods, fermented foods, or beverages.

[0046] In another aspect, the present invention provides a rice fermentation product comprising the rice fermentation liquid.

[0047] In some embodiments, the rice fermentation product exists in the form of liquid, paste, powder, flakes, or freeze-dried powder.

[0048] In some embodiments, the rice fermented product contains rice fermentation liquid and sugar substances.

[0049] In some embodiments, the mass-volume percentage of the sugars is 5% to 40%, preferably 5% to 30%, based on the volume of the rice fermentation liquid.

[0050] In some embodiments, the sugar is selected from one or more of glucose, sucrose, fructose, maltose, α-cyclodextrin, β-cyclodextrin, resistant dextrin, maltodextrin, xylitol, erythritol and galactose.

[0051] In some implementations, the fermented rice product is used in food.

[0052] In some implementations, the rice fermented product is used in baked goods, puffed foods, fermented foods, or beverages.

[0053] In some implementations, the fermented rice product is used in the preparation of pharmaceuticals, health foods, or infant foods.

[0054] Beneficial effects of the present invention

[0055] (1) The percentage of histidine in the rice fermentation liquid prepared by the method of the present invention is above 0.09%, and can reach up to 0.15%, and its histidine content is significantly improved.

[0056] (2) The rice fermentation liquid obtained by the preparation method of the present invention contains a variety of flavor substances, resulting in a rice fermentation liquid with a unique flavor, which improves the defect of rice having a single flavor.

[0057] (3) The rice fermentation liquid in this invention can be prepared into various forms of rice fermented food, which can be used to prepare medicine, health food or infant food.

[0058] Information on strain preservation

[0059] The Saccharomyces cerevisiae A3.12 used in this invention was deposited at the China Center for Type Culture Collection (CCTCC) on December 11, 2017, with accession number CCTCC NO: M 2017781. The deposit address is: Wuhan University, Wuhan, China, postal code: 430072; telephone: (027)-68754052. This strain has been published in the invention patent with patent application number CN201910662175.1 and publication number CN112245457A.

[0060] The Pichia pastoris C1.8 strain used in this invention was deposited at the China Center for Type Culture Collection (CCTCC) on December 11, 2017, with accession number CCTCCNO: M 2017780. The deposit address is: Wuhan University, Wuhan, China, postal code: 430072; telephone: (027)-68754052. This strain has been published in the invention patent with patent application number CN201910662175.1 and publication number CN112245457A.

[0061] The *Saccharomycopsis fibuligera* d6.16 used in this invention was deposited on July 19, 2019, at the China Center for Type Culture Collection (CCTCC), accession number CCTCC NO: M2019570, address: Wuhan University, Wuhan, China, postcode: 430072; telephone: (027)-68754052; this strain has been published in the invention patent application with patent application number CN202010713499.6 and publication number CN113966832A.

[0062] The Lactobacillus plantarum RPC5 used in this invention was deposited at the China Center for Type Culture Collection on July 19, 2019, with accession number CCTCC NO: M2019566, deposit address: Wuhan University, Wuhan, China, postal code: 430072; telephone: (027)-68754052; this strain has been published in the invention patent with patent application number CN202010713499.6 and publication number CN113966832A. Detailed Implementation

[0063] As described above, the purpose of this invention is to provide a rice fermentation broth with high histidine content, its preparation method, and its application.

[0064] In one specific embodiment of the present invention, a method for preparing rice fermentation broth with high histidine content is provided, comprising the following steps:

[0065] (1) Preparation of rice culture medium

[0066] The rice is ground into powder and sieved, and then prepared into a rice culture medium with a mass-volume percentage of 1% to 60% (for example, preparing a rice culture medium with a mass-volume percentage of 60% means that each 100 mL of rice culture medium contains 60 g of rice, i.e., the unit is g / mL).

[0067] (2) Enzymatic hydrolysis

[0068] Based on the volume of the rice culture medium obtained in step (1), add 0.05% to 1% by weight of an enzyme (e.g., 1% by weight of an enzyme means 1g of enzyme per 100mL of rice culture medium, i.e., g / mL). The enzyme is selected from one or more of amylase, saccharifying enzyme, and cellulase. Enzymatic hydrolysis is performed at 55–95°C for 20–40 minutes. Then, based on the volume of the rice culture medium obtained in step (1), add 0.01% to 1% by weight of a protease (e.g., 1% by weight of a protease means 1g of protease per 100mL of rice culture medium, i.e., g / mL). Enzymatic hydrolysis is performed at 50–60°C for 20–40 minutes. Finally, sterilization is performed at 100°C for 30 minutes.

[0069] (3) First fermentation

[0070] Based on the volume of the rice hydrolysate obtained in step (2), add 0.01% to 4.5% yeast by mass volume (for example, 1% yeast by mass volume means 1g of yeast per 100mL of rice hydrolysate, i.e., the unit is g / mL). The yeast is selected from one or more of Kluyveromyces, Saccharomyces cerevisiae, Pichia pastoris and Saccharomyces cerevisiae, and is cultured statically at a temperature of 28 to 40℃ for 12 to 48 hours.

[0071] (4) Preparation of culture medium and sterilization

[0072] Based on the total mass of the fermentation stock obtained in step (3), add 1-5% carbon source and 0.1-3% nitrogen source by mass and volume, and then sterilize at 100°C for 30 minutes. The carbon source is selected from one or more of glucose, fructose, sucrose, maltose, and hydrolyzed starch; the nitrogen source is selected from one or more of hydrolyzed soy protein, milk powder, and yeast extract.

[0073] (5) Second fermentation

[0074] The culture medium prepared in step (4) is inoculated with 0.01% to 1% lactic acid bacteria by mass volume (for example, 1% lactic acid bacteria by mass volume means that 100 mL of prepared culture medium contains 1 g of lactic acid bacteria, i.e., the unit is g / mL). The lactic acid bacteria are selected from one or more of Lactobacillus pentosus, Lactobacillus casei, Bifidobacterium longum, Bifidobacterium breve, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus breve and Lactobacillus reuteri, and are statically cultured at a temperature of 28 to 40°C for 12 to 48 hours.

[0075] (6) Sterilization

[0076] The rice slurry from step (5) that has undergone a second fermentation is treated at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid, and its nutritional components, flavor substances and histidine content are measured.

[0077] (7) Prepare fermented products of different forms from the rice fermentation liquid obtained in step (6).

[0078] Liquid fermented product: Based on the volume of rice fermentation liquid obtained in step (6), add or do not add sugar substances with a mass-volume percentage of 10% to 30% (for example, 10% sucrose means that 10g of sucrose is contained in every 100ml of rice fermentation liquid), wherein the sugar substances are selected from sucrose, glucose, fructose or maltose, and then sterilize at 100℃ for 30min to obtain liquid rice fermented product.

[0079] Paste fermented product: Based on the volume of rice fermentation liquid obtained in step (6), add 5% to 20% by mass volume of sugar, wherein the sugar is selected from one or more of sucrose, glucose, fructose and maltose, and concentrate under vacuum to control the moisture content to below 15% to obtain paste rice fermented product.

[0080] Powdered fermented products: Based on the volume of rice fermentation liquid obtained in step (6), add 1% to 20% by mass volume of dextrin, wherein the dextrin is selected from one or more of α-cyclodextrin, β-cyclodextrin, resistant dextrin and maltodextrin, and then spray powder. The spray powder process is as follows: the air inlet temperature is 150 to 160°C and the air outlet temperature is controlled above 90°C to obtain powdered rice fermented products.

[0081] Snowflake-shaped fermented products: Add a certain amount of rice flour to the rice fermentation liquid obtained in step (6), mix thoroughly so that the dry matter mass is controlled at 30% to 35%, and then dry it in a roller at 145°C. After drying, it is sorted by a swing granulator and then sieved to produce snowflake-shaped fermented rice products.

[0082] Freeze-dried fermented rice product: Based on the volume of rice fermentation liquid obtained in step (6), add 1% to 20% by mass volume of dextrin, wherein the dextrin is selected from one or more of α-cyclodextrin, β-cyclodextrin, resistant dextrin, and maltodextrin, freeze-dry to obtain freeze-dried rice fermented product powder.

[0083] (8) Preparation of finished product

[0084] The rice fermentation products in different forms in step (7) are prepared into various forms of food such as baked goods, puffed foods, fermented foods, and beverages.

[0085] Unless otherwise specified, the experimental methods in the following examples are generally performed under conventional conditions or as recommended by the manufacturer. Unless otherwise stated, the raw materials used in the following examples are all commercially available products. The sources of reagents and instruments used in the embodiments and comparative examples of this invention are shown in the table below:

[0086] Table 2. Reagents and instruments used in the examples.

[0087]

[0088]

[0089] The technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0090] Example 1

[0091] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0092] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% (w / v) of α-high-temperature amylase and hydrolyze at 90°C for 30 min. Then add 0.1% (w / v) of papain and hydrolyze at 55°C for 30 min. Sterilize the rice hydrolysate at 100°C for 30 min.

[0093] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, and 0.1% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0094] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0095] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0096] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content and flavor compounds in the rice fermentation liquid are then tested.

[0097] The histidine content in this invention was determined according to the method for detecting multiple free amino acids in Q / YB.J19.132-2020. The histidine content in the rice fermentation liquid obtained by step (6) was 0.15wt%, that is, 0.15g of histidine was contained in every 100g of rice fermentation liquid.

[0098] Flavor compounds in rice fermentation broth were analyzed using gas chromatography-mass spectrometry, as shown in the table below:

[0099] Table 3. Flavor composition analysis of rice fermentation liquid

[0100]

[0101] As can be seen from Table 3, rice culture medium can be enzymatically hydrolyzed and fermented to obtain rice fermentation liquid with rich flavor substances.

[0102] Example 2

[0103] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0104] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% (w / v) of α-high-temperature amylase and hydrolyze at 90°C for 30 min. Then add 0.1% (w / v) of papain and hydrolyze at 55°C for 30 min. Sterilize the rice hydrolysate at 100°C for 30 min.

[0105] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12 and 0.1% by weight of Pichia pastoris C1.8, and culture at 36°C for 24 hours.

[0106] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0107] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0108] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid obtained in step (6) is 0.12 wt%, that is, 0.12 g of histidine is contained in every 100 g of rice fermentation liquid.

[0109] Example 3

[0110] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0111] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% (w / v) of α-high-temperature amylase and hydrolyze at 90°C for 30 min. Then add 0.1% (w / v) of papain and hydrolyze at 55°C for 30 min. Sterilize the rice hydrolysate at 100°C for 30 min.

[0112] (3) Based on the volume of rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12 and incubate at 36°C for 24 hours.

[0113] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0114] (5) Then, 0.1% by weight of Lactobacillus plantarum RPC5 was inoculated and cultured at 37°C for 24 h.

[0115] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is found to be 0.14%, that is, 0.14g of histidine is contained in every 100g of rice fermentation liquid.

[0116] Example 4

[0117] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0118] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% α-high-temperature amylase by weight and volume, and hydrolyze at 90℃ for 30 min. Then add 0.1% papain by weight and volume, and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min.

[0119] (3) Based on the volume of rice hydrolysate obtained in step (2), add 1% by weight of Saccharomyces cerevisiae A3.12, 1% by weight of Pichia pastoris C1.8, and 1% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0120] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0121] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0122] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is 0.11%, that is, 0.11g of histidine is contained in every 100g of rice fermentation liquid.

[0123] Example 5

[0124] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0125] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% α-high-temperature amylase by weight and volume, and hydrolyze at 90℃ for 30 min. Then add 0.1% papain by weight and volume, and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min.

[0126] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.01% by weight of Saccharomyces cerevisiae A3.12, 0.01% by weight of Pichia pastoris C1.8, and 0.01% by weight of Saccharomycopsis fibuligerad6.16, and incubate at 36°C for 24 h.

[0127] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0128] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0129] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is found to be 0.13 wt%, that is, 0.13 g of histidine is contained in every 100 g of rice fermentation liquid.

[0130] Example 6

[0131] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0132] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% α-high-temperature amylase by weight and volume, and hydrolyze at 90℃ for 30 min. Then add 0.1% papain by weight and volume, and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min.

[0133] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, and 0.1% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0134] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage. Then sterilize at 100℃ for 30 min.

[0135] (5) Then inoculate with 1% by weight of Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0136] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is found to be 0.12 wt%, that is, 0.12 g of histidine is contained in every 100 g of rice fermentation liquid.

[0137] Example 7

[0138] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0139] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% α-high-temperature amylase by weight and volume, and hydrolyze at 90℃ for 30 min. Then add 0.1% papain by weight and volume, and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min.

[0140] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, and 0.1% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0141] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage. Then sterilize at 100℃ for 30 min.

[0142] (5) Then inoculate with 0.01% by weight of Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0143] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is found to be 0.12%, that is, 0.12g of histidine is contained in every 100g of rice fermentation liquid.

[0144] Example 8

[0145] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0146] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.05% α-high-temperature amylase at a mass-volume percentage, hydrolyze at 90℃ for 30 min, then add 0.1% papain at a mass-volume percentage, and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min.

[0147] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, and 0.1% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0148] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0149] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0150] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is found to be 0.09%, that is, 0.09g of histidine is contained in every 100g of rice fermentation liquid.

[0151] Example 9

[0152] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0153] (2) Based on the volume of the rice culture medium obtained in step (1), add 1% (w / v) of α-high-temperature amylase, hydrolyze at 90°C for 30 min, and then add 0.1% (w / v) of papain, hydrolyze at 55°C for 30 min. Sterilize the rice hydrolysate at 100°C for 30 min.

[0154] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, and 0.1% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0155] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0156] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0157] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is 0.11 wt%, that is, 0.11 g of histidine is contained in every 100 g of rice fermentation liquid.

[0158] Example 10

[0159] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0160] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% (w / v) of α-high-temperature amylase, hydrolyze at 90℃ for 30 min, then add 0.01% (w / v) of papain, and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min.

[0161] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, and 0.1% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0162] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0163] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0164] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is 0.11 wt%, that is, 0.11 g of histidine is contained in every 100 g of rice fermentation liquid.

[0165] Example 11

[0166] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0167] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% α-high-temperature amylase at a mass-volume percentage, hydrolyze at 90℃ for 30 min, then add 1% papain at a mass-volume percentage, and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min.

[0168] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, and 0.1% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0169] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0170] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0171] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is found to be 0.14%, that is, 0.14g of histidine is contained in every 100g of rice fermentation liquid.

[0172] Example 12

[0173] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0174] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.5% by weight of saccharifying enzyme, hydrolyze at 60°C for 30 min, and then add 0.5% by weight of papain, hydrolyze at 55°C for 30 min. Sterilize the rice hydrolysate at 100°C for 30 min.

[0175] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 0.5% by weight of Saccharomyces cerevisiae A3.12, 0.5% by weight of Pichia pastoris C1.8, and 0.5% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0176] (4) Based on the total mass of the fermentation stock obtained in step (3), add 3% glucose and 3% zinc-enriched yeast extract by mass percentage. Then sterilize at 100℃ for 30 minutes.

[0177] (5) Then inoculate with 0.5% Lactobacillus plantarum RPC5 and culture at 37°C for 48 h.

[0178] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the obtained rice fermentation liquid is 0.10%, that is, 0.10g of histidine is contained in every 100g of rice fermentation liquid.

[0179] Example 13

[0180] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0181] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% α-high-temperature amylase by weight and volume, and hydrolyze at 90℃ for 30 min. Then add 0.1% papain by weight and volume, and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min.

[0182] (3) Based on the volume of the rice hydrolysate obtained in step (2), add 1.5% by weight of Saccharomyces cerevisiae A3.12, 1.5% by weight of Pichia pastoris C1.8, and 1.5% by weight of Saccharomycopsis fibuligera d6.16, and incubate at 36°C for 24 h.

[0183] (4) Based on the total mass of the fermentation stock obtained in step (3), add 1% glucose and 0.2% zinc-enriched yeast extract by mass percentage, and then sterilize at 100℃ for 30 minutes.

[0184] (5) Then inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 h.

[0185] (6) The rice slurry from step (5) that has undergone a second fermentation is sterilized at a temperature above 90°C for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is found to be 0.09%, that is, 0.09g of histidine is contained in every 100g of rice fermentation liquid.

[0186] Comparative Example 1

[0187] (1) Grind glutinous rice into powder and sieve it. Prepare rice culture medium with a mass-volume percentage of 20%.

[0188] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% (w / v) of α-high-temperature amylase and hydrolyze at 90℃ for 30 min. Then add 0.1% (w / v) of papain and hydrolyze at 55℃ for 30 min. Sterilize the rice hydrolysate at 100℃ for 30 min. The histidine content in the rice hydrolysate was found to be 0.039%, meaning that 0.039 g of histidine was present in every 100 g of rice fermentation liquid. Analysis of the flavor compounds in the rice fermentation liquid using gas chromatography-mass spectrometry revealed that only the unfermented rice emulsion, which underwent enzymatic hydrolysis, did not contain any flavor compounds.

[0189] Comparative Example 2

[0190] (1) Grind the glutinous rice flour and sieve it, then prepare a rice culture medium with a mass volume percentage of 20%.

[0191] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% α-high temperature amylase at a mass-volume percentage, the enzymatic hydrolysis temperature is 90℃ and the time is 30min, and then add 0.1% papain at a mass-volume percentage, and enzymatically hydrolyze at a temperature of 55℃ for 30min.

[0192] (3) Based on the weight of the rice hydrolysate obtained in step (2), add 1% glucose and 0.2% zinc-rich yeast extract, and sterilize at 100°C for 30 minutes.

[0193] (4) Based on the volume of the rice culture medium obtained in step (3), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, 0.1% by weight of Saccharomycopsis fibuligera d6.16, and 0.1% by weight of Lactobacillus plantarum RPC5, and culture at 36°C for 24 h.

[0194] (5) The fermentation liquid obtained in step (4) is sterilized at a temperature above 90℃ for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid is 0.062%, that is, 0.062g of histidine is contained in every 100g of rice fermentation liquid.

[0195] Comparative Example 3

[0196] (1) Grind the glutinous rice flour and sieve it, then prepare a rice culture medium with a mass volume percentage of 20%.

[0197] (2) Based on the volume of the rice culture medium obtained in step (1), add 0.1% α-high temperature amylase at a mass-volume percentage, with a hydrolysis temperature of 90℃ and a hydrolysis time of 30 min. Then add 0.1% papain at a mass-volume percentage, with a hydrolysis temperature of 55℃ and a hydrolysis time of 30 min.

[0198] (3) Based on the weight of the rice hydrolysate obtained in step (2), add 1% glucose and 0.2% zinc-enriched yeast extract. Then sterilize at 100°C for 30 minutes.

[0199] (4) Then, inoculate with 0.1% Lactobacillus plantarum RPC5 and culture at 37°C for 24 hours; then sterilize the rice slurry after lactic acid bacteria fermentation at 100°C for 30 minutes.

[0200] (5) Based on the volume of the rice slurry obtained in step (4), add 0.1% by weight of Saccharomyces cerevisiae A3.12, 0.1% by weight of Pichia pastoris C1.8, and 0.1% by weight of Saccharomycopsis fibuligerad6.16, and incubate at 36°C for 24 hours.

[0201] (6) The fermentation liquid obtained in step (5) is sterilized at a temperature above 90℃ for 30 minutes to obtain rice fermentation liquid. The histidine content in the rice fermentation liquid was tested to be 0.089%, that is, 0.089g of histidine is contained in every 100g of rice fermentation liquid.

[0202] Application Example 1

[0203] Based on the volume of the rice fermentation liquid prepared in Example 1, 20% by mass / volume of sucrose was added, and then sterilized at 100°C for 30 minutes to obtain the liquid rice fermentation product.

[0204] Application Example 2

[0205] Based on the volume of the rice fermentation liquid prepared in Example 1, 20% by mass volume of sucrose was added, and the liquid was concentrated under vacuum to evaporate the water, controlling the moisture content to be below 15%, thus obtaining a paste-like rice fermentation product.

[0206] Application Example 3

[0207] Based on the volume of rice fermentation liquid prepared in Example 1, 10% by mass volume of maltodextrin was added and then sprayed with powder. The spraying process was as follows: the air inlet temperature was 150-160℃ and the air outlet temperature was controlled above 90℃ to obtain powdered rice fermentation products.

[0208] Application Example 4

[0209] Based on the volume of the rice fermentation liquid prepared in Example 1, add 5% by weight of rice flour (i.e., 5g of rice flour per 100ml of rice fermentation liquid) and dry it in a roller to obtain a snowflake-shaped rice fermentation product.

[0210] Application Example 5

[0211] Based on the volume of the rice fermentation liquid prepared in Example 1, 15%–30% sucrose by weight / volume was added to obtain a rice fermentation product as a slurry. 84.5 wt% indica rice flour, 15 wt% waxy potato starch, and 0.5 wt% edible salt were used as the total substrate ingredients. 12–15 kg of the above slurry was used per 100 kg of the mixed substrate for slurry preparation and shaping. The rice cake product was obtained through steaming, kneading, shaping, first drying, shrinking, moisture conditioning, puffing (at high temperature), and packaging processes.

[0212] Application Example 6

[0213] A premixed mixture of 350g low-gluten flour, 40g vegetable oil, 15g butter, 20g starch, and 6g active dry yeast was used. 120g of fermented rice from Example 1 was used for slurry preparation and dough preparation. The dough preparation time was 6 minutes, the fermentation time was 120 minutes, and the fermentation temperature was 38℃. The dough was sheeted using a sheeting machine and shaped using a mold. Cookies were then baked in an oven at 160℃ (top heat) and 140℃ (bottom heat) for 9 minutes, and packaged to obtain fermented soft cookie products.

[0214] Application Example 7

[0215] Using the rice fermentation broth prepared in Example 1 as the substrate, 10g of xylitol, 5g of erythritol, 1g of fructooligosaccharides, and 1g of galactooligosaccharides were added to every 100g of rice fermentation broth substrate; 5% by weight (meaning 5g of compound grain slurry per 100ml of rice fermentation broth) and 3% by weight (meaning 3g of compound vegetable slurry per 100ml of rice fermentation broth) were added; 0.5g of yeast extract, appropriate amounts of citric acid and malic acid were added for flavoring; and the mixture was packaged after UTH sterilization or pasteurization to obtain a rice fermented lactic acid bacteria beverage.

[0216] Application Example 8

[0217] Using 23g of rice fermented product (prepared in Example 1), 55g of fermented yogurt, 10g of trehalose, 10g of resistant dextrin, 1g of fructooligosaccharides, and 1g of galactooligosaccharides as substrates, all solid substances were pre-treated with rice fermentation broth and then thoroughly mixed with the fermented yogurt. The mixture was then processed using a colloid mill until no visible particles remained. The mixture was spread onto a mold and pre-frozen at -18℃ for 120 minutes. The fully frozen semi-finished product was then placed into a freeze-drying chamber, and the refrigeration and vacuum heating equipment were turned on. The freeze-drying process was carried out according to the set curve. After freeze-drying, the product had a moisture content of less than 3%. The product was then packaged to obtain the freeze-dried rice fermented yogurt product.

[0218] While the specific embodiments of the present invention have been described above, they are not intended to limit the scope of protection of the present invention. Based on the technical solutions of the present invention, various modifications or variations that can be made by those skilled in the art without creative effort are still within the scope of protection of the present invention.

Claims

1. A rice fermentation broth with high histidine content, characterized in that, The rice fermentation broth is obtained by first enzymatically hydrolyzing rice culture medium, and then successively fermenting it with yeast and lactic acid bacteria; wherein the mass percentage of histidine in the rice fermentation broth is above 0.09%; The preparation method of the high-histidine rice fermentation broth includes the following steps: (1) Grind the rice into powder and sieve it to prepare rice culture medium; (2) Add the first enzyme to the rice culture medium for the first enzymatic hydrolysis, then add the second enzyme for the second enzymatic hydrolysis, and finally obtain the enzymatic hydrolysate by enzyme inactivation treatment; the first enzyme is selected from one or two of amylase and saccharifying enzyme; the second enzyme is protease; (3) Add yeast to the enzymatic hydrolysate obtained in step (2) to carry out the first fermentation. The types and amounts of yeast added are as follows: based on the volume of rice enzymatic hydrolysate obtained in step (2), the mass-volume percentage of Saccharomyces cerevisiae A3.12 with preservation number CCTCC NO: M 2017781 is 0.01%-1%, the mass-volume percentage of Pichia pastoris C1.8 with preservation number CCTCC NO: M 2017780 is 0.01%-1%, and the mass-volume percentage of Saccharomyces cerevisiae d6.16 with preservation number CCTCC NO: M2019570 is 0.01%-1%. (4) Add carbon and nitrogen sources to the fermentation broth obtained in step (3) to prepare culture medium, and then sterilize it; (5) Inoculate lactic acid bacteria into the culture medium obtained in step (4) and carry out the second fermentation. The type and amount of lactic acid bacteria added are as follows: based on the volume of the culture medium obtained in step (4), the mass-volume percentage of Lactobacillus plantarum RPC5 with preservation number CCTCC NO: M2019566 is 0.01%-1%; (6) Sterilize the fermentation liquid obtained in step (5) to obtain rice fermentation liquid.

2. The high-histidine rice fermentation broth according to claim 1, wherein, The mass percentage of histidine in the rice fermentation broth is 0.09% - 0.3%.

3. A method for preparing high-histidine rice fermentation broth as described in claim 1 or 2, characterized in that, Includes the following steps: (1) Grind the rice into powder and sieve it to prepare rice culture medium; (2) Add the first enzyme to the rice culture medium for the first enzymatic hydrolysis, then add the second enzyme for the second enzymatic hydrolysis, and finally obtain the enzymatic hydrolysate by enzyme inactivation treatment; the first enzyme is selected from one or two of amylase and saccharifying enzyme; the second enzyme is protease; (3) Add yeast to the enzymatic hydrolysate obtained in step (2) to carry out the first fermentation. The types and amounts of yeast added are as follows: based on the volume of rice enzymatic hydrolysate obtained in step (2), the mass-volume percentage of brewer's yeast A3.12 is 0.01%-1%, the mass-volume percentage of Pichia pastoris C1.8 is 0.01%-1%, and the mass-volume percentage of saccharomyces d6.16 is 0.01%-1%. (4) Add carbon and nitrogen sources to the fermentation broth obtained in step (3) to prepare culture medium, and then sterilize it; (5) Inoculate lactic acid bacteria into the culture medium obtained in step (4) and carry out the second fermentation. The type and amount of lactic acid bacteria added are as follows: based on the volume of the culture medium obtained in step (4), the mass-volume percentage of Lactobacillus plantarum RPC5 is 0.01%-1%; (6) Sterilize the fermentation liquid obtained in step (5) to obtain rice fermentation liquid.

4. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (1), the rice is selected from one or more of the following: glutinous rice, japonica rice, indica rice, white rice, red rice, purple rice, and black rice.

5. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (1), the rice has a mesh size of 80-200.

6. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (1), the mass-volume percentage of the rice culture medium is 1%-60%.

7. The method for preparing high-histidine rice fermentation broth according to claim 4, wherein, In step (1), the mass-volume percentage of the rice culture medium is 10%-20%.

8. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (2), the mass-volume percentage of the first enzyme is 0.05%-1% based on the volume of the rice culture medium obtained in step (1).

9. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (2), the mass-volume percentage of the first enzyme is 0.1%-0.4% based on the volume of the rice culture medium obtained in step (1).

10. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (2), the first enzyme is α -High-temperature amylase.

11. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (2), the enzymatic hydrolysis temperature of the first enzyme is 55-95℃; and / or the enzymatic hydrolysis time is 20-40 min.

12. The method for preparing high-histidine rice fermentation broth according to claim 4, wherein, In step (2), the enzymatic hydrolysis temperature of the first enzyme is 55-95℃; and / or the enzymatic hydrolysis time is 20-40 min.

13. The method for preparing high-histidine rice fermentation broth according to claim 6, wherein, In step (2), the enzymatic hydrolysis temperature of the first enzyme is 55-95℃; and / or the enzymatic hydrolysis time is 20-40 min.

14. The method for preparing high-histidine rice fermentation broth according to claim 8, wherein, In step (2), the enzymatic hydrolysis temperature of the first enzyme is 55-95℃; and / or the enzymatic hydrolysis time is 20-40 min.

15. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (2), the mass-volume percentage of the second enzyme is 0.01%-1% based on the volume of the rice culture medium obtained in step (1).

16. The method for preparing high-histidine rice fermentation broth according to claim 4, wherein, In step (2), the mass-volume percentage of the second enzyme is 0.01%-1% based on the volume of the rice culture medium obtained in step (1).

17. The method for preparing high-histidine rice fermentation broth according to claim 6, wherein, In step (2), the mass-volume percentage of the second enzyme is 0.01%-1% based on the volume of the rice culture medium obtained in step (1).

18. The method for preparing high-histidine rice fermentation broth according to claim 8, wherein, In step (2), the mass-volume percentage of the second enzyme is 0.01%-1% based on the volume of the rice culture medium obtained in step (1).

19. The method for preparing high-histidine rice fermentation broth according to claim 11, wherein, In step (2), the mass-volume percentage of the second enzyme is 0.01%-1% based on the volume of the rice culture medium obtained in step (1).

20. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (2), the mass-volume percentage of the second enzyme is 0.1%-1% based on the volume of the rice culture medium obtained in step (1).

21. The method for preparing high-histidine rice fermentation broth according to claim 12, wherein, In step (2), the second enzyme is papain.

22. The method for preparing high-histidine rice fermentation broth according to claim 15, wherein, In step (2), the second enzyme is papain.

23. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (2), the enzymatic hydrolysis temperature of the second enzyme is 50-90℃; and / or the enzymatic hydrolysis time is 20-40 min.

24. The method for preparing high-histidine rice fermentation broth according to claim 8, wherein, In step (2), the enzymatic hydrolysis temperature of the second enzyme is 50-90℃; and / or the enzymatic hydrolysis time is 20-40 min.

25. The method for preparing high-histidine rice fermentation broth according to claim 12, wherein, In step (2), the enzymatic hydrolysis temperature of the second enzyme is 50-90℃; and / or the enzymatic hydrolysis time is 20-40 min.

26. The method for preparing high-histidine rice fermentation broth according to claim 15, wherein, In step (2), the enzymatic hydrolysis temperature of the second enzyme is 50-90℃; and / or the enzymatic hydrolysis time is 20-40 min.

27. The method for preparing high-histidine rice fermentation broth according to claim 3, wherein, In step (2), the enzymatic hydrolysis temperature of the second enzyme is 50-60℃.

28. The method for preparing high-histidine rice fermentation broth according to any one of claims 4-17, wherein, The temperature of the first fermentation step in step (3) is 28-40℃; and / or the fermentation time is 12-48h.

29. The method for preparing high-histidine rice fermentation broth according to claim 18, wherein, The temperature of the first fermentation step in step (3) is 28-40℃; and / or the fermentation time is 12-48h.

30. The method for preparing high-histidine rice fermentation broth according to claim 19, wherein, The temperature of the first fermentation step in step (3) is 28-40℃; and / or the fermentation time is 12-48h.

31. The method for preparing high-histidine rice fermentation broth according to any one of claims 4-19, wherein, Based on the volume of rice hydrolysate obtained in step (2), the mass-volume percentage of Saccharomyces cerevisiae A3.12 is 0.01%-0.4%, the mass-volume percentage of Pichia pastoris C1.8 is 0.01%-0.4%, and the mass-volume percentage of Saccharomyces d6.16 is 0.01%-0.4%.

32. The method for preparing high-histidine rice fermentation broth according to claim 20, wherein, Based on the volume of rice hydrolysate obtained in step (2), the mass-volume percentage of Saccharomyces cerevisiae A3.12 is 0.01%-0.4%, the mass-volume percentage of Pichia pastoris C1.8 is 0.01%-0.4%, and the mass-volume percentage of Saccharomyces d6.16 is 0.01%-0.4%.

33. The method for preparing high-histidine rice fermentation broth according to any one of claims 4-19, wherein, In step (4), the carbon source mass percentage is 1%-5% based on the total mass of the fermentation broth obtained in step (3).

34. The method for preparing high-histidine rice fermentation broth according to claim 33, wherein, In step (4), the carbon source is selected from one or more of glucose, fructose, sucrose and maltose.

35. The method for preparing high-histidine rice fermentation broth according to claim 34, wherein, In step (4), the carbon source is glucose.

36. The method for preparing high-histidine rice fermentation broth according to any one of claims 4-19, wherein, In step (4), the mass fraction of the nitrogen source is 0.1%-3% based on the mass of the fermentation broth obtained in step (3).

37. The method for preparing high-histidine rice fermentation broth according to any one of claims 4-19, wherein, In step (4), the mass fraction of the nitrogen source is 0.1%-1% based on the mass of the fermentation broth obtained in step (3).

38. The method for preparing high-histidine rice fermentation broth according to claim 37, wherein, In step (4), the nitrogen source is selected from one or more of hydrolyzed soybean protein, milk powder and yeast extract.

39. The method for preparing high-histidine rice fermentation broth according to claim 37, wherein, In step (4), the nitrogen source is a zinc-rich yeast extract.

40. The method for preparing high-histidine rice fermentation broth according to any one of claims 4-19, wherein, The fermentation temperature in step (5) is 28-40℃, and / or the fermentation time is 12-48h.

41. The method for preparing high-histidine rice fermentation broth according to claim 20, wherein, The fermentation temperature in step (5) is 28-40℃, and / or the fermentation time is 12-48h.

42. The method for preparing high-histidine rice fermentation broth according to claim 28, wherein, The fermentation temperature in step (5) is 28-40℃, and / or the fermentation time is 12-48h.

43. The method for preparing high-histidine rice fermentation broth according to claim 33, wherein, The fermentation temperature in step (5) is 28-40℃, and / or the fermentation time is 12-48h.

44. The method for preparing high-histidine rice fermentation broth according to claim 40, wherein, In step (5), the volume percentage of the lactic acid bacteria is 0.01%-0.4% based on the volume of the culture medium obtained in step (4).

45. A rice fermentation broth with high histidine content, characterized in that, The high-histidine rice fermentation broth is prepared by the method described in any one of claims 4-44.

46. ​​A fermented rice product, characterized in that, The rice fermentation product comprises the high histidine-containing rice fermentation liquid according to any one of claims 1, 2 or 45.

47. The rice fermentation product according to claim 46, wherein, The fermented rice products are available in liquid, paste, powder, or flake form.

48. The rice fermentation product according to claim 47, wherein, The powder is freeze-dried powder.

49. The rice fermentation product according to claim 46, wherein, The rice fermented product contains rice fermentation liquid and sugar substances.

50. The rice fermentation product according to claim 49, wherein, The sugar content is 5%-40% by mass volume based on the volume of rice fermentation liquid.

51. The rice fermentation product according to claim 49, wherein, The sugars are selected from glucose, sucrose, fructose, maltose, galactose, etc. α -Cyclodextrin, β - One or more of cyclodextrin, resistant dextrin, maltodextrin, xylitol and erythritol.

52. The use of the high-histidine rice fermentation liquid of claim 1, 2 or 45 or the rice fermentation product of any one of claims 46-51 in the preparation of food.

53. The application in the preparation of food according to claim 52, wherein, The food mentioned is baked goods, puffed foods, or fermented foods.

54. The application in the preparation of food according to claim 52, wherein, The food mentioned is a beverage.

55. The use of the high-histidine rice fermentation liquid of claim 1, 2 or 45 or the rice fermentation product of any one of claims 46-51 in the preparation of health food or infant food.

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