Application of aroma-producing yeast in fen-flavor liquor

Abstract

The invention discloses application of two Wickerhamomyces anomalus strains in ester extraction and aroma enhancement in the fermentation process of fen-flavor liquor. The two Wickerhamomyces anomalus strains are preserved in the China General Microbiological Culture Collection Center, the name of one Wickerhamomyces anomalus strain is SAU-F4, the preservation number of the Wickerhamomyces anomalus strain is CGMCC No.23919, the name of the other Wickerhamomyces anomalus strain is SAU-D13-Y15, and the preservation number of the other Wickerhamomyces anomalus strain is CGMCC No.27799. According to detection, the two Wickerhamomyces anomalus strains have good fermentation capacity in the fen-flavor liquor, the content of volatile flavor substances such as esters, alcohols and acids in the fen-flavor liquor intensified and fermented in a mixed bacteria inoculation mode is remarkably increased, and the Wickerhamomyces anomalus strains are rich in fragrance, comfortable and soft and clean in taste.

Description

Technical Field

[0001] The invention belongs to the technical field of microorganisms, and particularly relates to the application of two strains of high-ester abnormal Wickham yeast separated from liquor Daqu in extracting ester and enhancing aroma in light-flavor liquor. Background Art

[0002] As one of the six major distilled spirits in the world, liquor occupies a vast market in China and has very important economic value. The main aroma substances in liquor include esters, acids, aldehydes, alcohols and other aroma and flavor substances. The content and proportion of aroma substances in liquors of different aroma types vary greatly, which is one of the main factors affecting the flavor of liquor. Light-fragrance liquor is made from grains such as sorghum and barley. It is processed through a series of processes such as saccharification, fermentation, distillation, storage, aging and blending. It is colorless and transparent, with pure fragrance and elegant and coordinated complex aroma. It tastes refreshing, soft, sweet and has a long aftertaste. The ester substances that play an important role in light-fragrance liquor include ethyl acetate and ethyl lactate. The ratio between them is one of the important factors determining the aroma quality of light-fragrance liquor.

[0003] Ester production through microbial fermentation is an important source of ester substances in the production process of liquor. Aroma yeast is also called ester-producing yeast, which mainly belongs to film-forming yeast or Candida. Wickerhamomyces anomalus ) is an important aroma yeast that can produce aroma components mainly composed of esters. It promotes the synthesis of esters in the process of liquor brewing, especially important esters in liquor such as ethyl hexanoate and ethyl acetate. It is widely used in the brewing of liquor, rice wine and fruit wine. The enhanced fermentation of aroma yeast has the advantages of low cost, good effect and ester production. It is widely used in fermented foods, especially in the production of fermented foods such as liquor, soy sauce and vinegar, playing an important role in the formation of aroma and flavor.

[0004] Therefore, the development and utilization of aroma yeast has received widespread attention. The use of two or more microorganisms to mix and ferment liquor can improve the nutritional and flavor properties of the fermentation liquid as much as possible by utilizing the synergistic effect between strains, significantly increase the types and content of volatile substances, and make the aroma and taste of liquor richer. Therefore, screening out high-quality aroma yeasts, applying two or more aroma yeasts to liquor fermentation, and improving the problems of thin aroma and poor typicality of liquor fermented with commercial brewing yeast are of great significance to the quality of liquor and the development of the industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 To enhance the total acid and total ester content of light-fragrant liquor fermented by strains SAU-F4 and SAU-D13-Y15.

[0007] Figure 2The content of volatile flavor substances in the light-fragrant liquor fermented by strains SAU-F4 and SAU-D13-Y15. Summary of the invention

[0008] The purpose of the present invention is to provide an application method of two aroma yeasts with good fermentation performance in light-fragrance liquor.

[0009] Another object of the present invention is to provide a light-fragrance liquor with a high content of ester compounds and a preparation method thereof, which has a soft taste and a prominent flavor.

[0010] To achieve the above purpose, the technical solution provided by the present invention is as follows:

[0011] Two strains of abnormal Wickham yeast were prepared into an aroma-producing yeast intensifying agent, which was mixed and inoculated into liquor grains, and the finished light-fragrant liquor was obtained through saccharification, fermentation and distillation.

[0012] Furthermore, the abnormal Wickham yeast ( Wickerhamomyces anomalus ), named SAU-F4, was deposited in the China General Microbiological Culture Collection Center (CGMCC) on November 15, 2021, at No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, with the deposit number CGMCC No. 23919; Abnormal Wickham yeast ( Wickerhamomyces anomalus ), named SAU-D13-Y15, was deposited in the China General Microbiological Culture Collection Center (CGMCC) on July 5, 2023, at No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, with the deposit number CGMCC No.27799.

[0013] Unless otherwise specified, S. anomalisatus SAU-F4 CGMCC No. 23919 is referred to herein as SAU-F4, and S. anomalisatus SAU-D13-Y15 CGMCC No. 27799 is referred to herein as SAU-D13-Y15.

[0014] The aroma yeast enhancing agent comprising SAU-F4 and SAU-D13-Y15 of the present invention can be mixed with bran koji powder and inoculated into steamed grains, the inoculation amount is 0.01-0.05%, and then mixed with lees, piled into a rectangle with a height of 30 cm, saccharified and piled for 1 day, and fermented in a pool at 20-30° C. for 5 days. After fermentation is completed, distillation is repeated to obtain wine, forming a cycle, and finally a finished light-fragrant liquor is obtained.

[0015] The application of aroma yeast in light-flavor liquor, the total ester of liquor was detected after distillation, and the physical and chemical indicators were used to evaluate the effect of strains SAU-F4 and SAU-D13-Y15 on the ester and aroma enhancement of light-flavor liquor. The total acid and total ester content of the experimental group with strains SAU-F4 and SAU-D13-Y15 increased significantly, the total amount of acid esters increased by 21.46%, the content of volatile flavor substances increased by 15.22%, of which the ethyl acetate content increased by 14.54%, and the ethyl lactate content increased by 37.81%. After sensory identification, the light-flavor liquor fermented with SAU-F4 and SAU-D13-Y15 had a soft taste and a refreshing aroma. DETAILED DESCRIPTION

[0017] The experimental methods described in the following examples are conventional methods unless otherwise specified; the reagents and biological materials described are commercially available unless otherwise specified.

[0018] In the following examples, the percentages are by mass unless otherwise specified.

[0019] The following examples further illustrate the specific implementation of the present invention, but are not limited to these examples.

[0020] Example 1 The strains SAU-F4 and SAU-D13-Y15 were applied to the solid-state fermentation of light-fragrance liquor, and the steps were as follows:

[0021] (1) Ingredients and saccharification accumulation The weight of a cellar wine mash is 1250 kg, containing 26% grain mash (40% sorghum, 15% rice, 20% glutinous rice, 16% wheat, 9% corn), 6% bran and 0.12% bran powder, and the rest of the ingredients are the remaining grains from the previous round of wine distillation. After the steamed grain mash is spread out and cooled, the prepared SAU-F4 and SAU-D13-Y15 mixed fungus powder and bran powder (experimental group) are evenly sprinkled on it. No fungus powder is added to the control group. After fully mixing, it is mixed with the wine dregs and piled into a rectangle with a height of 30 cm. The temperature at the center of the material is not lower than 25℃. The saccharification is piled for 24 hours. After saccharification, obvious hyphae should be seen on the surface of the material.

[0022] (2) Fermentation in cellar After saccharification and accumulation, the mash is transferred to the cellar, and the moisture content of the mash is controlled to 55% by adding bran shells. The temperature of the mash is 25℃, the surface is covered with plastic film, and the surroundings are compacted with sandbags. The fermentation time is 5 days, and the entire brewing cycle is 6 days (1 day saccharification and 5 days fermentation). After fermentation, the wine is distilled in a steamer barrel, and the alcohol content of the original wine after distillation is controlled to be 61%-63%.

[0023] Example 2 Determination of total acid and total esters in Fen-flavor liquor fermented by strains SAU-F4 and SAU-D13-Y15 Index determination method: The determination of total acid and total ester shall refer to the acid-base titration method and saponification reflux method in GB / T 10345-2022.

[0024] Index measurement results: As shown in Table 2, the alcohol content of the original liquor distilled from the experimental group and the control group was 67%vol, and the following data was converted to 45%vol alcohol content. According to the relevant grading standards in GB / T 10781.2-2022 "Quality Requirements for Liquor Part 2: Light-Fragrance Liquor", the physical and chemical indicators in the original liquor were tested. The total acid content of the liquor in the experimental group was 0.70 g / L, which was 48.93% higher than that of the control group, and greater than 0.50 g / L to meet the special grade standard; the total ester content was 1.79 g / L, which was 13.29% higher than that of the control group, and greater than the special grade standard of 1.10 g / L; the total amount of acid esters increased by 21.46% compared with the control group. In summary, SAU-F4 and SAU-D13-Y15 can effectively improve the aroma quality of light-fragrance liquor by applying them to the enhanced fermentation of light-fragrance liquor.

[0025] Table 1 Total acid and total ester content of light-flavor liquor Index (g / L) Experimental Group Control group Total acid 0.7 0.47 Total esters 1.79 1.58 Total Acid Acids 2.49 2.05

[0026] Example 3 Determination of Volatile Flavor Substances in Liquor Headspace solid phase micro extraction (SPME) conditions: add 4 mL of liquor sample to the headspace bottle, add 1.3 g of sodium chloride, add 0.1 mg / mL of methyl heptanoate as an internal standard, equilibrate at 43°C for 30 min, and adsorb in the headspace at 43°C for 40 min. Then take out the extraction head and insert it into the gas chromatography injection port at 230°C for thermal desorption for 5 min.

[0027] Gas chromatography conditions: Agilent VF-Waxms column (60 m×0.25 mm, 0.5 um), helium (He) flow rate 1 mL / min; temperature program: splitless injection; initial temperature 40°C, hold for 3 min, increase to 60°C at 2°C / min, hold for 1 min, then increase to 120°C at 4°C / min, hold for 1 min, then increase to 230°C at 6°C / min, hold for 3 min; injection port temperature 230°C;

[0028] Mass spectrometry conditions: electron ionization (EI) source, interface temperature 230°C, ion source temperature 200°C, electron energy 70 eV, mass spectrometry scanning range 40.00-800.00 m / z, solvent delay time 2 min.

[0029] The results are shown in Table 2. A total of 46 volatile flavor substances were detected in the light-flavor liquor inoculated with SAU-F4 and SAU-D13-Y15 for enhanced fermentation, and the total volatile flavor substance content reached 5.6456 g / L, which was 15.22% higher than that of the control group. Among them, there were 17 ester substances in the experimental group, with a total content of 1.1794 g / L, which was 13.68% higher than that of the control group. In addition, the contents of ethyl acetate and ethyl lactate in the experimental group were 0.9991 g / L and 0.0667 g / L, respectively, which were 14.54% and 37.81% higher than those of the control group. A total of 11 alcohol volatile flavor substances were detected in the light-flavor liquor inoculated with SAU-F4 and SAU-D13-Y15, with a total content of 2.6514 g / L. Compared with the control group, the total content of alcohol volatile flavor substances increased by 14.31%, and the content of acid volatile flavor substances was 46.91% higher than that of the control group. In summary, the contents of ester, alcohol and acid volatile flavor substances in the light-flavor liquor inoculated with SAU-F4 and SAU-D13-Y15 for enhanced fermentation were higher than those in the light-flavor liquor in the control group, indicating that mixed inoculation of SAU-F4 and SAU-D13-Y15 can significantly increase the content of volatile flavor substances in light-flavor liquor.

[0030] Table 2 Types and contents of volatile flavor substances in light-fragrance liquor

[0031] Example 4 Sensory Indexes of Liquor A panel of 20 people (10 women and 10 men, aged between 20 and 40) who had undergone sensory training were selected to evaluate the sensory quality of the wine samples. Mouthwash was provided between the evaluations of different samples to avoid the residual effect of the aftertaste. The panelists gave sensory quality scores for the light-flavor liquor, including scores for color, aroma, flavor, and acidity.

[0032] The sensory scoring results showed that the light-fragrance liquor fermented by mixed bacteria inoculation of SAU-F4 and SAU-D13-Y15 scored higher than the control group and commercially available light-fragrance liquor in terms of aroma and taste indicators, and the total sensory evaluation score was higher than that of the control group and commercially available light-fragrance liquor. In summary, the light-fragrance liquor fermented by mixed bacteria inoculation of SAU-F4 and SAU-D13-Y15 has a comfortable aroma and a refreshing taste, and is easily favored by consumers.

[0033] Table 3 Sensory score table of light-fragrance liquor

Claims

1. Application of two strains of abnormal Wickham yeast in light-fragrance liquor. The two strains of yeast are used to prepare an aroma-generating yeast enhanced bacterial agent, which is inoculated into the white wine lees. After saccharification, fermentation and distillation, a light-fragrance liquor with sweet and refreshing taste, long aftertaste and obvious light fragrance style is obtained.

2. The two strains of abnormal Wickham yeast according to claim 1, wherein one strain of abnormal Wickham yeast ( Wickerhamomyces anomalus )SAU-F4, characterized by It was deposited in the China General Microbiological Culture Collection Center on November 15, 2021, with the deposit number CGMCC No.23919; an abnormal Wickham yeast ( Wickerhamomyces anomalus ) SAU-D13-Y15, characterized in that it was deposited in the China General Microbiological Culture Collection Center on July 5, 2023, with the deposit number CGMCC No.27799.

3. The aroma-producing yeast enhancing agent according to claim 1, characterized in that: The invention comprises the two strains of abnormal Wickham yeast according to claim 2, wherein the ratio of the two strains of abnormal Wickham yeast in the microbial agent is 1:1, and the concentration is 10 9 ~10 10 CFU / g.

4. A light-fragrance liquor, characterized in that: The invention is prepared by enhanced fermentation of the two strains of abnormal Wickham yeast as claimed in claim 2.

5. A method for preparing a light-fragrance liquor, characterized in that: The method comprises the following steps: (a) inoculating the aroma yeast fortifying agent as claimed in claim 3 and bran koji powder into the steamed mash, wherein the mash comprises 40% sorghum, 15% glutinous rice, 20% glutinous rice, 16% wheat and 9% corn, and the inoculation amount of the aroma yeast fortifying agent is 0.01-0.05% (m / m), and then mixing the mixture with the remaining lees from the previous round of distillation; (b) piling the evenly mixed lees into a rectangle with a height of 30 cm, saccharifying and piling for 1 day, and fermenting in a pool for 5 days at a fermentation temperature of 20-30°C; (c) after the fermentation is completed, repeatedly distilling and extracting the liquor to form a cycle, and finally obtaining a finished light-fragrant liquor.

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