Screening method of special glutinous rice for wine brewing

Abstract

The invention discloses a screening method of special sticky rice for wine brewing. The screening method comprises the following steps: step 1, detecting chain length distribution of starch of different varieties of sticky rice; obtaining a white spirit sample corresponding to each variety of glutinous rice; step 2, detecting flavor substances in the liquor sample corresponding to each variety of glutinous rice, and respectively carrying out sensory evaluation; and step 3, carrying out correlation analysis on the chain length distribution of the glutinous rice starch of each variety, the flavor substance of the white spirit sample and the sensory evaluation to obtain the optimal glutinous rice variety and the chain length distribution of the starch in the glutinous rice variety. According to the method, the influence of the fine structure of the glutinous rice starch on the Luzhou-flavor liquor is illuminated by measuring the fine structure of the glutinous rice starch, the importance of the glutinous rice in brewing is determined, and a certain theoretical basis is provided for selecting glutinous rice varieties for producing the Luzhou-flavor liquor and breeding the special glutinous rice for brewing.

Description

Technical Field

[0001] The invention relates to the field of wine-making methods, and in particular to a method for screening glutinous rice specially used for wine-making. Background Art

[0002] Glutinous rice is one of the brewing raw materials of Chinese Luzhou-flavor liquor, which is mainly composed of starch (70%-80%) and protein (6%-8%). Starch is not only the most important carbon source used by microorganisms in liquor fermentation, but also the source of esters, alcohols and acids. Therefore, determining the screening method of glutinous rice for brewing can select glutinous rice varieties that are more suitable for brewing Luzhou-flavor liquor, and has guiding significance for the selection and breeding of glutinous rice for brewing.

[0003] In glutinous rice starch, the content of amylopectin accounts for more than 99% of the total starch content, and it contains only a very small amount of amylose. Amylopectin has a highly branched structure, which is connected by a large number of shorter branches. Therefore, the chain length distribution of amylopectin can reflect the fine structure of starch, which largely determines the cooking characteristics of starch, affects the saccharification of starch during fermentation, and then affects the synthesis of flavor substances, which will ultimately affect the quality of liquor. Therefore, it is necessary to provide a method for using the fine structure of glutinous rice starch for glutinous rice screening for winemaking, so as to solve the problem that the screening process of glutinous rice for winemaking in the prior art is complicated and it is difficult to obtain the optimal glutinous rice variety. Summary of the invention

[0004] The invention provides a method for screening glutinous rice for brewing, so as to solve the problems in the prior art that the screening process of glutinous rice for brewing is complicated and it is difficult to obtain the optimal result.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for screening glutinous rice for brewing wine comprises the following steps:

[0007] Step 1, detecting the chain length distribution of starch of different varieties of glutinous rice; and using different varieties of glutinous rice to conduct a five-grain fermentation experiment to obtain liquor samples corresponding to each variety of glutinous rice;

[0008] Step 2, detecting flavor substances in the liquor samples corresponding to each variety of glutinous rice in step 1, and evaluating the sensory properties of the liquor samples corresponding to each variety of glutinous rice;

[0009] Step 3: Perform a spearman correlation analysis based on the chain length distribution of glutinous rice starch of each variety obtained in step 1, the flavor substances of the liquor samples corresponding to each variety of glutinous rice obtained in step 2, and the sensory evaluation of the liquor samples corresponding to each variety of glutinous rice, and select glutinous rice with a suitable starch chain length based on the correlation analysis results.

[0010] In a further step 1, starch is obtained from different varieties of glutinous rice respectively, and then debranching treatment is performed respectively, and then the products obtained by the debranching treatment are analyzed using an ion chromatography system, thereby obtaining the chain length distribution of starch of each variety of glutinous rice.

[0011] In the further step 1, each variety of glutinous rice is made into a slurry, and then the precipitate is taken after screening, and then NaOH solution is added to the precipitate, stirred, and centrifuged to remove the upper yellow impurities, and then the product with the upper yellow impurities removed is washed, dried, and ground to obtain the glutinous rice starch of this variety.

[0012] In the further step 2, a dual-channel gas chromatograph is used to determine the flavor substances in the liquor samples corresponding to each variety of glutinous rice.

[0013] In a further step 2, the sensory evaluation of the liquor samples corresponding to each variety of glutinous rice is performed by manual scoring.

[0014] The present invention clarifies the influence of the fine structure of glutinous rice starch on Luzhou-flavor liquor by measuring the fine structure of glutinous rice starch, and establishes the importance of glutinous rice in brewing, providing a certain theoretical basis for selecting glutinous rice varieties for Luzhou-flavor liquor production and breeding glutinous rice for brewing. Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The present invention provides a more accurate method for screening glutinous rice for brewing.

[0016] 2. The screening method of the present invention reduces the complicated and numerous screening and testing work in the past.

[0017] 3. The present invention will help to improve the quality of liquor products.

[0018] 4. Provide a certain theoretical basis for the selection of varieties for the future production of Luzhou-flavor liquor and the breeding of glutinous rice for brewing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 1 is a chain length distribution diagram of five kinds of glutinous rice starch in the embodiments of the present invention.

[0020] Figure 2 It is a chromatogram of liquor samples obtained by fermenting five kinds of glutinous rice in the embodiments of the present invention.

[0021] Figure 3 1 is a graph showing the correlation analysis results between the chain length distributions of five glutinous rice starches and flavor substances in the embodiments of the present invention. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the solutions of the present invention, the following will describe the implementation methods of the present invention in detail in conjunction with the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve corresponding technical effects can be fully understood and implemented accordingly. The embodiments of the present invention and the various features in the embodiments can be combined with each other without conflict, and the technical solutions formed are all within the protection scope of the present invention.

[0023] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "include" and "have" in the specification and claims of the present invention and the above drawings and any modifications thereof are intended to cover non-exclusive inclusions.

[0025] This embodiment discloses a method for screening glutinous rice for brewing wine, and takes five varieties of glutinous rice, namely, Wanken Glutinous Rice No. 1, Wanken Glutinous Rice No. 2, Wanken Glutinous Rice No. 3, Special Glutinous Rice No. 2072, and Huaiyuan Yuan Glutinous Rice, as examples for explanation, including the following steps:

[0026] Step 1, obtaining starch from five varieties of glutinous rice, namely, Wankennuo No. 1, Wankennuo No. 2, Wankennuo No. 3, Tenuo 2072, and Huaiyuan Yuannuo, and detecting the chain length distribution of the starch of each variety of glutinous rice; and using these five varieties of glutinous rice to conduct a five-grain fermentation experiment to obtain liquor samples corresponding to each variety of glutinous rice.

[0027] Specifically in this embodiment, the starch acquisition process of each variety of glutinous rice is as follows:

[0028] After soaking each variety of glutinous rice in distilled water overnight, put it into a wall breaking machine to make a slurry, pass the slurry through an 80-mesh sieve, and then centrifuge to remove the supernatant and take the precipitate. Then, add a 0.20% NaOH solution to the precipitate at a solid-liquid ratio of 1:5, then stir it magnetically at 25°C for 4 hours, and then centrifuge it at 3000r / min for 20 minutes, and then remove the upper yellow impurities in the product. Finally, the product with the upper yellow impurities removed is repeatedly washed with water until neutral, and then placed in an oven at 40°C for drying, and then ground and passed through a 100-mesh sieve to obtain the starch of this variety of glutinous rice.

[0029] In this embodiment, the chain length distribution detection process of starch of each variety of glutinous rice is as follows:

[0030] First, the starch of five varieties of glutinous rice was debranched. Then, the products obtained by debranching the starch of each variety of glutinous rice were analyzed using the Thermo ICS5000 ion chromatography system (ICS5000+, Thermo Fisher Scientific, USA). When using the ion chromatography system for analysis, Dionex TM CarboPac TM PA200 (250*4.0mm, 10um) liquid chromatography column, injection volume of 5μL; mobile phase A: 0.2M NaOH; phase B: 0.2M NaOH / 0.2MNaAC; column temperature of 30°C; flow rate of 0.4mL / min; elution gradient: 0minA / B (90:10V / V), 10minA / B (90:10V / V), 30min A / B (40:60V / V), 50minA / B (40:60V / V); 50.1minA / B (90:10V / V); 60minA / B (90:10V / V). Finally, in this embodiment, the chain length distribution test results of the starch of the five varieties of glutinous rice are as follows. Figure 1 As shown, according to Figure 1 The chain length distribution result table shown in Table 1 is obtained. Table 1 is as follows:

[0031] Table 1 Chain length distribution test results of five varieties of glutinous rice starch

[0032]

[0033] In this embodiment, a 35L fermentation tank was used to conduct a five-grain fermentation experiment on each variety of glutinous rice. The fermentation experiment of each variety of glutinous rice was carried out 3 times. The fermentation experiment process included the steps of crushing, moistening, steaming, cooling, spreading koji, fermentation and distillation, thereby obtaining the white wine sample corresponding to each variety of glutinous rice.

[0034] Step 2: Detect the flavor substances in the liquor samples corresponding to each variety of glutinous rice in step 1, and evaluate the sensory properties of the liquor samples corresponding to each variety of glutinous rice.

[0035] Specifically in this embodiment, a dual-channel gas chromatograph Agilent 7890B is used to determine the flavor components of the liquor samples corresponding to each variety of Noni. When the dual-channel gas chromatograph is measured, the chromatographic column is a capillary column DB-Wax UI60m×250μm×0.25μm. The heating program during the measurement is: the initial temperature is 32°C for 1min, raised to 60°C at 30°C / min and maintained for 1min, then raised to 100°C at 5°C / min and maintained for 1min, and then raised to 210°C at 4°C / min and maintained for 20min. The gas flow rate during the measurement is: hydrogen 30mL / min, air 400mL / min, tail gas 25mL / min. The injection mode during the measurement is: split injection. The split ratio during the measurement is: 45:1. The split flow rate during the measurement is: 45mL / min. The injection volume during the measurement is: 1μL. During the determination, internal standard 1 is tert-amyl alcohol, internal standard 2 is n-amyl acetate, and internal standard 3 is 2-ethylbutyric acid. In this embodiment, the peak area obtained by the determination is finally used to quantify the flavor substances in the liquor sample, and the content of each flavor substance component is calculated by the internal standard method. Finally, the flavor substances in the liquor samples corresponding to the five kinds of glutinous rice determined in this embodiment are as follows Figure 2 shown.

[0036] In this embodiment, 10 tasters with more than two years of experience in sensory analysis conducted sensory evaluation and scored five kinds of glutinous rice fermented liquor samples. The higher the score, the better the sensory evaluation. The evaluation results are shown in Table 2:

[0037] Table 2 Sensory evaluation of five kinds of glutinous rice liquor samples

[0038]

[0039]

[0040] Step 3: Combine the chain length distribution of glutinous rice starch of each variety obtained in step 1, the flavor substances of liquor samples corresponding to the five varieties of glutinous rice obtained in step 2, and the sensory evaluation of liquor samples corresponding to the five varieties of glutinous rice, and perform a spearman correlation analysis. The correlation analysis process is as follows:

[0041] The Spearman correlation coefficient was selected to calculate the correlation between starch chain length, main flavor substances and sensory evaluation results. The distribution test proposed by Fisher was used to confirm its significance. The correlation heat map was obtained using Origin software. The results are shown in the figure. Figure 2 , Figure 3 shown.

[0042] from Figure 2It can be seen that the glutinous rice variety with the best sensory evaluation is Wankennuo No. 2, the DP (25–36) of the glutinous rice starch of this variety is 11.98, and the DP (≥36) is 12.49. Figure 3 It can be seen that through phase relationship analysis, it can be determined that since the proportion of DP (25–36) and DP (≥36) is positively correlated with sensory evaluation, glutinous rice (Wanken Glutinous Rice No. 2) with a higher proportion of starch chain length in these two intervals is more suitable for brewing.

[0043] In addition, from Figure 3 It can also be seen that the proportion of DP (6–12) is positively correlated with the content of ethyl acetate and ethyl butyrate. Therefore, if it is necessary to produce liquor with high ethyl acetate and ethyl butyrate content, glutinous rice varieties (Huaiyuan Yuannuo) with a high proportion of starch DP (6–12) can be selected.

[0044] Therefore, this embodiment finally analyzes the influence of starch chain length distribution on the content of flavor substances by performing spearman correlation analysis. The appropriate content of flavor substances can improve the sensory evaluation of liquor. According to the correlation analysis results, by selecting glutinous rice with a suitable starch chain length, the required content of flavor substances can be increased, thereby improving the quality of liquor.

[0045] The above embodiment describes a method for screening glutinous rice for winemaking. It can be seen from the above embodiment that the chain length of glutinous rice starch can affect the generation of flavor substances in liquor. When selecting glutinous rice varieties, it is only necessary to select varieties with corresponding starch chain lengths to obtain liquor products with the desired flavor after fermentation, thereby achieving the need to improve the quality of liquor.

[0046] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. The embodiments described in the present invention are merely descriptions of the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention. The various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction, and such combinations should also be regarded as the contents disclosed in the present disclosure as long as they do not violate the concept of the present invention. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0047] The present invention is not limited to the specific details of the above-mentioned embodiments. Within the technical concept of the present invention and without departing from the design concept of the present invention, various modifications and improvements made to the technical solution of the present invention by technical personnel in this field should fall within the protection scope of the present invention. The technical contents for which protection is sought in the present invention have been fully recorded in the claims.

Claims

1. A method for screening glutinous rice for brewing wine, characterized in that: The following steps are involved: Step 1, detecting the chain length distribution of starch of different varieties of glutinous rice; and using different varieties of glutinous rice to conduct a five-grain fermentation experiment to obtain liquor samples corresponding to each variety of glutinous rice; Step 2, detecting flavor substances in the liquor samples corresponding to each variety of glutinous rice in step 1, and evaluating the sensory properties of the liquor samples corresponding to each variety of glutinous rice; Step 3: Perform a spearman correlation analysis based on the chain length distribution of glutinous rice starch of each variety obtained in step 1, the flavor substances of the liquor samples corresponding to each variety of glutinous rice obtained in step 2, and the sensory evaluation of the liquor samples corresponding to each variety of glutinous rice, and select glutinous rice with a suitable starch chain length based on the correlation analysis results.

2. The method for screening glutinous rice for brewing wine according to claim 1, characterized in that: In step 1, starch is obtained from different varieties of glutinous rice, and then debranching treatment is performed respectively. Then, the products obtained by the debranching treatment are analyzed using an ion chromatography system, thereby obtaining the chain length distribution of starch of each variety of glutinous rice.

3. The method for screening glutinous rice for brewing wine according to claim 2, characterized in that: In step 1, each variety of glutinous rice is made into slurry, and then precipitated after sieving, and then NaOH solution is added to the precipitate, stirred, and centrifuged to remove upper yellow impurities, and then the product with the upper yellow impurities removed is washed, dried, and ground to obtain the variety of glutinous rice starch.

4. The method for screening glutinous rice for brewing wine according to claim 1, characterized in that: In step 2, a dual-channel gas chromatograph is used to determine the flavor substances in the liquor samples corresponding to each variety of glutinous rice.

5. The method for screening glutinous rice for brewing wine according to claim 1, characterized in that: In step 2, the sensory evaluation of the liquor samples corresponding to each variety of glutinous rice is performed by manual scoring.

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