CN107815375A - Citrinin content and the method for preparing wine of rice fermented with red yeast in a kind of reduction red yeast rice - Google Patents

Abstract

The invention discloses a method for reducing the citrinin content in red yeast rice and preparing red yeast rice wine. The method for reducing the citrinin content in red koji comprises the following steps: compounding the soy-flavored koji, the light-flavored high-temperature koji, the light-flavored medium-temperature koji, and the Luzhou-flavored koji to obtain the pretreated koji compound koji; Compounding the above-mentioned distiller's koji without ultrasonic crushing treatment to obtain the original distiller's koji compound koji; then compounding the two to obtain the final distiller's koji mixture; adding evening primrose flower powder to water after steam explosion treatment, and adding laccase for enzymatic solution treatment to obtain the pretreated evening primrose liquid; inoculate the activated Monascus seed liquid into the culture liquid, and ferment for 2-2.5d; then add the final mixed distiller's yeast and pretreated evening primrose liquid, and ferment for 5-6d, Monascus fermented liquid with reduced citrinin content was obtained. The fermented liquid is filtered and blended with the fragrance-type base wine to obtain red yeast rice wine. The invention reduces the citrinin content in the red yeast rice by controlling the metabolism of the monascus fungus.

Description

A method for reducing citrinin content in red yeast rice and preparing red yeast rice wine

technical field

The invention belongs to the field of brewing engineering, in particular to a method for reducing the citrinin content in red yeast rice and preparing red yeast rice wine.

Background technique

Monascus pigment is a natural pigment produced during the growth and metabolism of Monascus. It is widely used in food coloring in my country because of its bright red color, strong tinting strength, good stability, and natural taste. Monascus pigment also has a variety of biological activities, such as the obvious inhibitory effect on some conditions-induced carcinogenic effects. In 1995, French scholar BLANC P J confirmed that Monascus purpureus (Monascus purpureus) CBS 109.07 and (Monascus ruber van Tieghem) also produced Monascidin A during pigment metabolism, and confirmed that the substance was a mycotoxin-citrinin, which caused people to Concerns about the safety of Monascus pigment. Citrinin, also known as citrinin, was first discovered to be produced by Penicillium in the 1930s, and it was highly valued as an antibiotic. Later, it was found to be nephrotoxic, and the possibility of using it as a therapeutic antibiotic was ruled out, and it was identified as a fungus. toxin. The target organ of citrinin is the kidney. Ingestion of citrinin can cause nephrotoxicity in various experimental animals, which is characterized by enlarged kidneys and eventually renal failure. Studies have also found that citrinin has teratogenic effects, damages liver metabolism, is carcinogenic and mutagenic, and may inhibit the central nervous system.

The European Union (EU) issued Regulation No. 212/2014, which amended (EC) No 1881/2006 and supplemented the maximum limit of food contaminant citrinin in Monascus fermented rice food supplements The value is 2mg/kg, and this limit value will be further reviewed based on the risk assessment of citrinin in other foods and the toxicity of citrinin. Monascus pigment has not been approved as a food additive in the European Union and the United States for a long time, largely because the problem of citrinin content cannot be effectively controlled.

my country's red yeast rice has a long history of production and application, and the scale is constantly expanding. However, because citrinin cannot be effectively controlled in red yeast rice products, there are potential safety problems in red yeast rice products, and it has caused great damage to the export trade of red yeast rice in my country. Big restrictions. Therefore, seeking to reduce the method of citrinin content in the red yeast rice product becomes the key to solving the above problems.

Contents of the invention

The purpose of the invention is to overcome the problems in the prior art and provide a method for reducing the content of citrinin in red yeast rice. The object of the present invention is also to provide a kind of method for preparing red yeast rice wine.

The object of the present invention is achieved through the following technical solutions:

A method for reducing citrinin content in red yeast rice, comprising the steps of:

(1) Preparation of distiller's yeast

The sauce-flavored koji, light-flavored high-temperature koji, light-flavored medium-temperature koji, and Luzhou-flavored koji that have been processed by ultrasonic crushing are compounded at a mass ratio of 0.7-1:1-1.2:4-5:2-2.5 to obtain a pre- Dealing with distiller's koji complexes.

The sauce-flavored koji, the light-flavored high-temperature koji, the light-flavored medium-temperature koji, and the strong-flavored koji are compounded according to the mass ratio of 1-1.2:2-2.3:3.5-4:1-1.2 to obtain the original koji compound koji.

The pretreated koji compound koji is compounded with the original koji compound koji at a mass ratio of 7-9:1 to obtain the final koji mixed koji.

(2) Pretreatment of evening primrose flowers

The evening primrose flower is ultrasonically crushed into powder, and the evening primrose flower powder is subjected to steam explosion treatment and added to water with a mass 3-4 times its mass, and laccase is added for enzymolysis treatment to obtain a pretreated evening primrose flower liquid.

(3) fermentation

Inoculate the monascus seed liquid into the culture liquid, and ferment for 2-2.5 days; then add the final mixed distiller's yeast with a mass of 1-3% of the fermented mash and 0.3-0.5% of the pretreated evening primrose liquid, and ferment for 5-6 days to obtain Monascus fermentation broth with reduced citrinin content.

In step (2), the condition of steam explosion is preferably 1.5MPa holding pressure for 6-8min, blasting 3-5 times; the addition of laccase is preferably 1-3% of the evening primrose flower powder mass, and the condition of enzymolysis is preferably Insulate at 30-35°C for 2-4h.

The formula of the culture medium described in step (3) is preferably: malt powder 20-25g, peptone 1-2g, glucose 2-3g, MgSO ₄ 0.5g, 1000mL water, pH 5.8.

In step (3), the fermentation temperature is preferably 30-35° C., and the rotation speed is preferably 130-160 r/min.

A method for preparing red koji wine, comprising the following steps: blending the filtrate obtained by filtering the monascus fermented liquid obtained by the above method with a fragrance type base wine to obtain red koji wine. Preferably, the degree of the fragrance-type base wine is 60 degrees; the blending volume ratio of the filtrate obtained by filtering the Monascus fermented liquid and the fragrance-type base wine is 2:7.

The invention utilizes an innovative process to effectively control the metabolism of Monascus, reduce the citrinin content in Monascus, and prepare a slightly fragrant Flavored red yeast rice wine.

Detailed ways

The following examples are used to further illustrate the present invention, but should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

Example 1

1. Materials and equipment

Monascus: Monascus CCTCC AF93208. Sauce-flavored Daqu, Fen-flavored high-temperature Daqu, and Fen-flavored medium-temperature distiller’s koji: all were purchased from Liangshan Changjiu Biological Koji Co., Ltd. Luzhou-flavor koji: Ruihua Biological Koji Co., Ltd., Longmatan District, Luzhou City. Laccase: Shanghai Guchen Biotechnology Co., Ltd.

JXZD series ultrafine pulverizer: Anqiu Jingxin Powder Processing Equipment Co., Ltd. Ultrasonic Crusher LC-N-4.3: Ningbo Licheng Instrument Co., Ltd. Steam blasting machine QB-200: Hebi Zhengdao Heavy Machinery Factory.

2. Method

(1) Preparation of culture medium

Monascus seed culture solution: 10g sucrose, 3g peptone, 0.5g K ₂ HPO ₄ , 1000mL water, pH 5.8, sterilized at 121°C for 20min.

Monascus fermentation broth: malt powder 20g, peptone 1g, glucose 2g, MgSO ₄ 0.5g, 1000mL tap water, pH 5.8, sterilized at 121°C for 20min.

(2) Preparation of distiller's yeast

Maotai-flavored Daqu, Fen-flavored high-temperature Daqu, Fen-flavored medium-temperature distiller’s koji, and Luzhou-flavored distiller’s koji were ultrasonically crushed by an ultrasonic crusher for 20 minutes to obtain pretreated Maotai-flavored Daqu, Fen-flavored high-temperature Daqu, Fen-flavored medium-temperature distiller’s koji, and Luzhou-flavored koji Distiller's yeast.

Preparation of pretreated koji compound koji: Pretreated sauce-flavored koji, pretreated light-flavored high-temperature koji, pretreated light-flavored medium-temperature koji, and pretreated Luzhou-flavored koji in a mass ratio of 1:1:4:2. Match, obtain the pretreatment distiller's yeast compound song.

Preparation of original distiller's koji compound koji: the sauce-flavored koji, light-flavored high-temperature koji, light-flavored medium-temperature koji, and strong-flavored koji were compounded at a mass ratio of 1:2:4:1 to obtain the original jiujiu compounded koji.

Preparation of the final koji mixture: compound the pretreated koji compound koji with the original koji compound koji at a mass ratio of 9:1 to obtain the final koji mixture.

(3) Pretreatment of evening primrose flowers

The commercially available evening primrose flowers were ultrafinely pulverized with an ultrasonic crusher. Put the pulverized powder into a steam blasting machine, keep the pressure at 1.5MPa for 6 minutes, and blast 3 times. Add 0.1% of its mass laccase to the blasted evening primrose powder, add water with 3 times the mass of the blasted evening primrose powder, and keep warm at 35° C. for 2 hours to obtain pretreated evening primrose flower liquid.

(4) fermentation

Activation of Monascus: Add 5 mL of sterile water to the slant of Monascus CCTCC AF93208 test tube, stir it with an inoculation needle, transfer it into a 250 mL Erlenmeyer flask containing 50 mL of seed culture solution, and cultivate it at 35°C for 24 hours at 160 r/min to obtain Monascus seed liquid.

Liquid Fermentation of Monascus: Take 2mL of Monascus seed liquid into a 250mL Erlenmeyer flask containing 50mL of fermentation medium, ferment for 2 days at 35°C and 160r/min, then add the final mixed koji with 1% of the mass of fermented mash, add fermentation The pretreated evening primrose flower liquid with a mash mass of 0.3% was fermented at 35° C. and 160 r/min for 6 days to obtain a Monascus fermented liquid.

(4) Determination of color value and citrinin content of Monascus fermented liquid

1) Determination of color value of pigment

Method for measuring the color value of alcohol-soluble pigments: Monascus fermented liquid is centrifuged at 5000r/min for 10 minutes, the supernatant is taken, diluted with 70% ethanol to a certain number of times, and then filtered in a water bath at 60°C for 1 hour; the filtrate is then diluted with 70% ethanol to a certain number of times , respectively measure OD ₅₀₅ , OD ₄₆₅ , and OD ₄₁₀ , and calculate the color values of the alcohol-soluble red, orange, and yellow pigments according to color value=OD×dilution factor/volume of the obtained fermentation broth.

Method for measuring the color value of water-soluble pigments: Monascus fermented liquid was centrifuged at 5000r/min for 10 minutes, the supernatant was taken, diluted with distilled water to a certain number of times, and then filtered in a water bath at 60°C for 1 hour; the filtrate was diluted with distilled water to a certain number of times, and the OD was measured respectively ₅₀₅ , OD ₄₆₅ , OD ₄₁₀ , according to color value=OD×dilution factor/volume of fermented broth obtained, calculate the color value of water-soluble red, orange and yellow pigments.

The total color value is the sum of the color value of the alcohol-soluble pigment and the color value of the water-soluble pigment.

2) Determination of citrinin content

Take 10mL of Monascus fermented liquid and centrifuge at 5000r/min for 10min, add 20mL of 70% ethanol solution to the supernatant and mix evenly, filter it with a 0.22μm microporous membrane and perform high performance liquid chromatography according to the national standard GB/T 5009.222-2008 detection.

The measurement results are: the color value of Monascus fermented liquid is 2.97U/mL, and the content of citrinin is 0.0165mg/mL.

(5) Preparation of red yeast rice wine

Monascus fermented liquid was first centrifuged at 5000r/min for 15min, then filtered with filter paper, and the filtrate was blended with Fen-flavor base wine (Sichuan Baishiyuan Liquor Industry Co., Ltd., 60 degrees) in a volume ratio of 2:7 to obtain reddish color and taste. Fen-flavored health-care red yeast rice wine that is soft and full, with a slightly strong aroma.

Comparative test 1

Referring to Example 1, after 2 days of fermentation, the final mixed koji was not added to the fermented mash, and other operations were the same as in Example 1. The measured pigment concentration in the Monascus fermented liquid was 2.82U/mL, and the citrinin content was 0.0173mg/mL .

Comparative test 2

With reference to Example 1, after 2 days of fermentation, the final mixed distiller's koji added in the fermented mash was changed to add the same amount of original distiller's koji compound koji, and other operations were the same as in Example 1, and the pigment concentration in the Monascus fermented liquid measured was 2.10 U/s. mL, citrinin content is 0.0166mg/mL.

Comparative test 3

With reference to Example 1, after fermentation 2d, the final mixed distiller's yeast that adds in the fermented mash changes the distiller's yeast that adds following different situations into:

Add 0.9% of the pretreated Maotai-flavored Daqu and 0.1% of the Maotai-flavored Daqu by the mass of the fermented mash;

Add 0.9% of the pretreated fragrance-type high-temperature Daqu and 0.1% of the fragrance-type high-temperature Daqu by the mass of the fermented mash;

Adding 0.9% of the pretreated fragrance-type medium-temperature Daqu and 0.1% of the fragrance-type medium-temperature Daqu by the mass of the fermented mash;

Add 0.9% pre-treated Luzhou-flavor Daqu and 0.1% Luzhou-flavor Daqu by the mass of fermented mash.

Other operations are the same as in Example 1, and the corresponding pigment concentration and citrinin content in the Monascus fermented liquid of measurement are: pigment concentration is 2.12U/mL, and citrinin content is 0.0179mg/mL; Pigment concentration is 2.10U/mL, The citrinin content was 0.0176mg/mL; the pigment concentration was 2.69U/mL, and the citrinin content was 0.0168mg/mL; the pigment concentration was 1.98U/mL, and the citrinin content was 0.0191mg/mL.

Comparative test 4

Referring to Example 1, after 2 days of fermentation, no pretreated evening primrose flower liquid was added to the fermented mash, and other operations were the same as in Example 1. The measured pigment concentration in the Monascus fermented liquid was 2.92 U/mL, and the citrinin content was 0.021 mg/mL.

Comparative test 5

Referring to Example 1, ferment 2d, add the same amount of ultrafine pulverized evening primrose flower liquid (without steam explosion treatment and laccase treatment) in the fermented mash, other operations are the same as in Example 1, in the Monascus fermented liquid measured The pigment concentration is 2.91U/mL, and the citrinin content is 0.019mg/mL.

Comparative test 6

With reference to Example 1, ferment for 2 days, do not add the final mixed distiller's yeast and pretreated evening primrose flower liquid, continue to ferment for 6 days, and other operations are the same as Example 1, the measured pigment concentration in the Monascus fermented liquid is 2.81U/mL, citrinin The content is 0.022mg/mL.

Comparative test 7

Referring to Example 1, after 2 days of fermentation, add the final mixed distiller's yeast and pre-treated evening primrose flower liquid into the fermented mash to add yeast liquid with a mass of 1.6% of the fermented mash, and other operations are the same as in Example 1. The pigment concentration in the medium is 3.11U/mL, and the citrinin content is 0.0171mg/mL.

Among them, the yeast liquid was obtained by the following treatment: 50 μL of Saccharomyces cerevisiae ATCC 36859 seed liquid was inserted into 5 mL of YEPD (peptone 20g/L, yeast extract 10g/L, glucose 20g/L, pH 6.0, sterilized at 121°C for 20min) Incubate in a large test tube at 30°C for 8 hours at 160r/min.

Comparative experiment 8

With reference to Example 1, the evening primrose flower powder is not treated with laccase, but is treated with cellulase, and other operations are the same as in Example 1. The measured pigment concentration in the Monascus fermented liquid is 2.91U/mL, and the citrinin content is 0.0179mg /mL.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (8)

1. a method for reducing citrinin content in red yeast rice, is characterized in that: comprise the steps: (1) Preparation of distiller's yeast The sauce-flavored koji, light-flavored high-temperature koji, light-flavored medium-temperature koji, and Luzhou-flavored koji that have been processed by ultrasonic crushing are compounded at a mass ratio of 0.7-1:1-1.2:4-5:2-2.5 to obtain a pre- Dealing with distiller's koji complexes; Compounding the sauce-flavored Daqu, the light-flavored high-temperature Daqu, the faint-flavored medium-temperature liquor, and the Luzhou-flavored liquor according to the mass ratio of 1-1.2:2-2.3:3.5-4:1-1.2 to obtain the original liquor koji compound song; Compounding the pretreated distiller's koji compound koji with the original distiller's koji compound koji in a mass ratio of 7-9:1 to obtain the final distiller's koji mixture; (2) Pretreatment of evening primrose flowers The evening primrose flower is ultrasonically crushed into powder, and the evening primrose flower powder is steam-exploded and added to water with a mass 3-4 times its mass, and laccase is added for enzymatic hydrolysis to obtain the pretreated evening primrose flower liquid; (3) fermentation Inoculate the monascus seed liquid into the culture liquid, and ferment for 2-2.5 days; then add the final mixed distiller's yeast with a mass of 1-3% of the fermented mash and 0.3-0.5% of the pretreated evening primrose liquid, and ferment for 5-6 days to obtain Monascus fermentation broth with reduced citrinin content. 2. the method for reducing citrinin content in red yeast rice according to claim 1, is characterized in that: in step (2), the condition of steam explosion is 1.5MPa holding pressure 6-8min, blasting 3-5 times. 3. the method for reducing citrinin content in red yeast rice according to claim 1, is characterized in that: in step (2), the add-on of laccase is 1-3% of evening primrose flower powder quality, and enzymolysis The condition is 30-35°C for 2-4h. 4. the method for reducing citrinin content in red yeast rice according to claim 1, is characterized in that: the formula of the nutrient solution described in step (3) is: malt powder 20-25g, peptone 1-2g, glucose 2-3g, MgSO ₄ 0.5g, 1000mL water, pH5.8. 5. The method for reducing citrinin content in red yeast rice according to claim 1, characterized in that: in step (3), the fermentation temperature is 30-35°C. 6. A method for preparing red koji wine, characterized in that: comprising the steps of: filtering the Monascus fermented liquid obtained by the method according to any one of claims 1-5, and blending the gained filtrate with the fragrance type base wine , get red yeast rice wine. 7. The method for preparing red yeast rice wine according to claim 6, characterized in that: the degree of the fragrance type base wine is 60 degrees. 8. The method for preparing red koji wine according to claim 6 or 7, characterized in that: the blending volume ratio of the filtrate obtained by filtering the monascus fermented liquid and the fragrance type base wine is 2:7.