Method for improving flavor of yellow rice wine and yellow rice wine

Abstract

The application provides a method for improving the flavor of yellow rice wine and the yellow rice wine, and the method comprises the following steps: subjecting distiller's grains to heat treatment by using microwaves; mixing the heat-treated distiller's grains with a compound protease and lactic acid bacteria to perform fermentation treatment, thereby preparing a flavor enhancement liquid; the compound protease comprises protease 1 and protease 2; mixing the flavor enhancement liquid with yellow rice wine fermentation liquid, thereby preparing a mixed wine body; the mass ratio of the yellow rice wine fermentation liquid to the flavor enhancement liquid is 8:2-9:1; mixing the mixed wine body with protease 2 and then performing ultrasonic intermittent treatment, so as to accelerate the generation of yellow rice wine flavor substances; the addition amount of protease 2 is 0.01 g / L-0.015 g / L, based on the volume of the mixed wine body; the process parameters of the ultrasonic intermittent treatment comprise: the ultrasonic power is 60 W-80 W, the ultrasonic treatment is performed once every 12 h-24 h, and the ultrasonic time is 10 min-15 min each time. The method for improving the flavor of yellow rice wine shortens the storage time.

Description

Technical Field

[0001] This application relates to the field of rice wine preparation technology, and in particular to methods for improving the flavor of rice wine and rice wine itself. Background Technology

[0002] Freshly brewed rice wine contains unstable molecules with disordered molecular arrangement, making it unsuitable for immediate sale. Furthermore, it typically has a slight off-flavor, a rough, harsh, and less mellow taste, and a weak aroma that is prone to change. Rice wine needs to be stored for a period of time to allow its molecules to undergo a series of complex chemical and physical changes, such as oxidation, esterification, aldehyde removal, and association, in order to achieve a rich aroma, smooth taste, and mellow flavor, while also harmonizing its various components and increasing the content of flavor compounds. However, the traditional process of storing alcoholic beverages relies solely on natural temperature for energy, making it a very slow process. Summary of the Invention

[0003] Based on this, this application provides a method and a type of rice wine for enhancing the flavor of rice wine, so as to significantly enhance the flavor of rice wine while shortening the time required to enhance the flavor of rice wine.

[0004] The first aspect of this application provides a method for enhancing the flavor of rice wine, comprising the following steps:

[0005] Microwave heat treatment is used to treat the distiller's grains;

[0006] The heat-treated lees are mixed with a complex protease and lactic acid bacteria and then fermented to prepare a flavor-enhancing liquid; the complex protease includes protease 1 and protease 2, protease 1 includes a neutral protease and protease 2 includes an acidic protease.

[0007] The flavor-enhancing liquid is mixed with the rice wine fermentation liquid to prepare a mixed wine; the mass ratio of the rice wine fermentation liquid to the flavor-enhancing liquid is 8:2-9:1.

[0008] The mixed wine and the protease 2 were mixed and subjected to intermittent ultrasonic treatment to accelerate the generation of flavor substances in the rice wine. The amount of protease 2 added was 0.01g / L-0.015g / L based on the volume of the mixed wine. The process parameters of the intermittent ultrasonic treatment included: ultrasonic power of 60W-80W, ultrasonic treatment once every 12h-24h, and ultrasonic treatment time of 10min-15min each time.

[0009] In some embodiments, the power of the microwave is 600W-800W.

[0010] In some embodiments, the heat treatment time is 10-15 minutes.

[0011] In some embodiments, the mass of the complex protease is 10 ppm to 15 ppm of the mass of the heat-treated distiller's grains.

[0012] In some embodiments, the mass ratio of protease 1 to protease 2 in the complex protease is 1:1.

[0013] In some embodiments, the mass of the lactic acid bacteria is 1‰-1.5‰ of the mass of the heat-treated distiller's grains.

[0014] In some embodiments, the fermentation treatment is carried out at a temperature of 30°C-37°C for a duration of 48h-72h.

[0015] In some embodiments, the temperature of the intermittent ultrasonic treatment is 20°C-30°C.

[0016] In some embodiments, the duration of intermittent ultrasonic treatment is 7 days.

[0017] In some embodiments, the raw materials for preparing the rice wine fermentation liquid include one or more of rice and wheat.

[0018] The second aspect of this application provides a type of rice wine, which is obtained by treating the rice wine fermentation liquid using the method for enhancing the flavor of rice wine as described in the first aspect of this application.

[0019] The aforementioned method for enhancing the flavor of Shaoxing wine involves using microwaves to heat-treat the fermenting lees, disrupting the protein structure and releasing more functional sites. This, combined with various enzyme preparations and fermentation, produces a flavor-enhancing liquid. Adding a specific amount of this flavor-enhancing liquid to the Shaoxing wine fermentation liquid increases the content of flavor substrates. Furthermore, combining this with intermittent ultrasonic treatment of the mixed wine using specific process parameters generates even more flavor compounds, making it suitable for applications in the food fermentation industry. During the intermittent ultrasonic treatment, a specific amount of protease is also added. Combined with the ultrasonic action, this accelerates the decomposition of large protein molecules introduced from the lees and remaining in the wine, improving the appearance and increasing the product's value. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application and to more completely understand this application and its beneficial effects, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A process flow diagram for improving the flavor of Shaoxing wine is provided as one embodiment.

[0022] Figure 2 The results show the determination of volatile components and content of the rice wine products prepared in Example 2 and Comparative Example 1. Detailed Implementation

[0023] To facilitate understanding of this application, a more complete description of the application will be provided below with reference to relevant embodiments. Preferred embodiments of the application are given below. However, the application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0025] As used herein, the terms "and / or," "or / and," and "and / or" encompass any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. It should be noted that when at least three items are connected using at least two conjunctions selected from "and / or," "or / and," and "and / or," it should be understood that, in this application, the technical solution undoubtedly includes solutions connected by "logical AND," and also undoubtedly includes solutions connected by "logical OR."

[0026] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0027] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0028] This document only specifically discloses some numerical ranges. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, just as any upper limit can be combined with any other upper limit to form an unspecified range. Furthermore, each individually disclosed point or single value can itself serve as a lower or upper limit and be combined with any other point or single value or with other lower or upper limits to form an unspecified range.

[0029] Unless otherwise specified, the temperature parameters in this application may be either constant temperature processing or processing within a certain temperature range. The constant temperature processing allows temperature fluctuations within the precision range controlled by the instrument, such as ±5°C, ±4°C, ±3°C, ±2°C, or ±1°C.

[0030] In this document, the term "suitable" as used in phrases such as "suitable combination," "suitable method," and "any suitable method" refers to the ability to implement the technical solution of this application, solve the technical problem of this application, and achieve the expected technical effect of this application.

[0031] In this application, terms such as "further," "even further," and "particularly" are used to describe purposes and indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0032] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0033] In the description of the application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0034] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions. Unless otherwise specified, all technical features and optional technical features of this application can be combined to form new technical solutions.

[0035] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, but sequentially is preferred.

[0036] Freshly brewed rice wine needs to be stored for a period of time to develop its rich aroma, smooth taste, and mellow flavor, allowing its various components to harmonize and increasing the content of flavor compounds. However, the traditional storage process for alcoholic beverages relies solely on natural temperature for energy, making it a very slow process.

[0037] In addition, non-biological sediments are prone to form in rice wine during storage. Protein is one of the main causes of sedimentation in rice wine. The instability of protein colloidal solutions, the association between proteins and polyphenols, and the oxidation of proteins by dissolved oxygen all affect the stability of the wine and lead to sedimentation.

[0038] Based on the above problems, this application uses microwave-treated lees to prepare flavor-enhancing liquid, mixes the flavor-enhancing liquid with rice wine fermentation liquid, adds protease and combines it with intermittent ultrasonic treatment, which effectively improves the flavor of rice wine and enhances the stability of rice wine.

[0039] One or more embodiments of this application provide a method for enhancing the flavor of Shaoxing wine, comprising the following steps: heat-treating the lees with microwaves; mixing the heat-treated lees with a complex protease and lactic acid bacteria and then fermenting the mixture to prepare a flavor-enhancing liquid; the complex protease includes protease 1 and protease 2, protease 1 including a neutral protease and protease 2 including an acidic protease; mixing the flavor-enhancing liquid with the Shaoxing wine fermentation liquid to prepare a mixed wine; the mass ratio of the Shaoxing wine fermentation liquid to the flavor-enhancing liquid is 8:2-9:1; mixing the mixed wine with protease 2 and then subjecting it to intermittent ultrasonic treatment to accelerate the generation of Shaoxing wine flavor substances; the amount of protease 2 added is 0.01g / L-0.015g / L based on the volume of the mixed wine; the process parameters for the intermittent ultrasonic treatment include: ultrasonic power of 60W-80W, ultrasonic treatment once every 12h-24h, and each ultrasonic treatment lasting 10min-15min.

[0040] It should be noted that microwave heat treatment of the lees produces a uniform golden-brown color with a caramelized aroma, disrupts the protein structure, provides more action sites, and improves utilization. The flavor-enhancing liquid contains more flavor substrates, promoting the formation of flavor compounds during the storage of rice wine. Intermittent low-frequency ultrasonic treatment of the mixed wine accelerates the formation of flavor compounds. Adding protease to the mixed wine further breaks down the large protein molecules introduced from the lees and present in the wine itself, reducing the turbidity of the rice wine product. The final result is rice wine with excellent flavor and clarity.

[0041] Understandably, the method for enhancing the flavor of Shaoxing wine provided in this application involves heat-treating the lees with microwaves to disrupt the protein structure, releasing more action sites in the proteins, and combining this with various enzyme preparations and fermentation to produce a flavor-enhancing liquid. Adding a specific amount of the flavor-enhancing liquid to the Shaoxing wine fermentation liquid increases the content of flavor substrates in the wine. Combining this with intermittent ultrasonic treatment of the mixed wine with specific process parameters generates even more flavor compounds, making it suitable for applications in the food fermentation industry. Furthermore, a specific amount of protease is added during the intermittent ultrasonic treatment; combined with ultrasound, this accelerates the decomposition of large protein molecules introduced from the lees and remaining in the wine, improving the appearance of the Shaoxing wine and increasing its value.

[0042] The rice wine treated with this method exhibits a 24% increase in total ester content and a 79.6% increase in ethyl lactate content. It also boasts a superior overall flavor profile and a richer, more complex aroma, with a significant increase in floral and fruity flavor compounds and a more pronounced nutty aroma. Furthermore, the turbidity of the rice wine product is reduced by 65%.

[0043] As an example, the mass ratio of rice wine fermentation liquid to flavor-enhancing liquid can be, but is not limited to, 8:2, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1, 8:1, 8.5:1, 9:1, or any range between two of the above mass ratios. When the mass ratio of rice wine fermentation liquid to flavor-enhancing liquid is within the above ranges, the flavor substrate of the rice wine fermentation liquid can be significantly increased, with minimal impact on the sensory and physicochemical properties of the rice wine.

[0044] The amount of protease 2 added, based on the volume of the mixed wine, can be, but is not limited to, 0.01 g / L, 0.011 g / L, 0.012 g / L, 0.013 g / L, 0.014 g / L, 0.015 g / L, or any range between two of the above amounts. When the amount of protease 2 added is within the above range, the turbidity of the rice wine product can be significantly reduced, avoiding the influence of the flavor-enhancing liquid on the product's appearance.

[0045] The ultrasonic power during intermittent ultrasonic processing can be, but is not limited to, 60W, 61W, 62W, 63W, 64W, 65W, 66W, 67W, 68W, 69W, 70W, 71W, 72W, 73W, 74W, 75W, 76W, 77W, 78W, 79W, 80W, or any range between two of the above ultrasonic powers.

[0046] The interval between each ultrasonic intermittent treatment can be, but is not limited to, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h, 24h, or any two of the above times.

[0047] The duration of each ultrasonic intermittent treatment can be, but is not limited to, 10 min, 11 min, 12 min, 13 min, 14 min, 15 min, or any range between two of the above times.

[0048] When the ultrasonic power, the time interval between each treatment, and the time of each ultrasonic treatment are within the above range, the esterification reaction rate of rice wine during storage can be accelerated, the generation of flavor substances can be promoted, and the sensory flavor will not deteriorate due to excessive ultrasonic time.

[0049] In some implementations, the microwave power is 600W-800W; for example, it can be, but is not limited to, 600W, 610W, 620W, 630W, 640W, 650W, 660W, 670W, 680W, 690W, 700W, 710W, 720W, 730W, 740W, 750W, 760W, 770W, 780W, 790W, 800W, or any range between two of the above power values.

[0050] As one possible implementation, the heat treatment time is 10 min to 15 min; for example, it can be, but is not limited to, 10 min, 11 min, 12 min, 13 min, 14 min, 15 min, or any two of the above time ranges.

[0051] It should be noted that when the microwave power and heat treatment time used for heat treatment of the lees are within the above range, the residual protein structure in the lees can be effectively destroyed, making it easier to further process and utilize, enhancing the caramel flavor, and preventing overheating that produces a burnt taste.

[0052] In some embodiments, the mass of the complex protease is 10 ppm to 15 ppm of the mass of the heat-treated lees; for example, it can be, but is not limited to, 10 ppm, 11 ppm, 12 ppm, 13 ppm, 14 ppm, 15 ppm or any range between two of the above values.

[0053] In some embodiments, the mass ratio of protease 1 to protease 2 in the complex protease is 1:1. As one possible implementation, the mass of lactic acid bacteria is 1‰-1.5‰ of the mass of the heat-treated distiller's grains; for example, it can be, but is not limited to, 1‰, 1.1‰, 1.2‰, 1.3‰, 1.4‰, 1.5‰, or any range between any two of the above values.

[0054] It should be noted that when the mass of the complex protease, the mass ratio of protease 1 to protease 2 in the complex protease, and the amount of lactic acid bacteria are all within the above ranges, the proteins in the distiller's grains can be effectively degraded and various organic acids can be produced.

[0055] In some embodiments, the fermentation temperature is 30℃-37℃; for example, it can be, but is not limited to, 30℃, 31℃, 32℃, 33℃, 34℃, 35℃, 36℃, 37℃ or any range between two of the above temperatures.

[0056] As one possible implementation method, the fermentation time is 48h-72h; for example, it can be, but is not limited to, 48h, 50h, 52h, 54h, 56h, 58h, 60h, 62h, 64h, 66h, 68h, 70h, 72h, or any range between two of the above times.

[0057] In some embodiments, the temperature of the intermittent ultrasonic treatment is 20°C-30°C; for example, it can be, but is not limited to, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, or any range between two of the above temperatures. When the temperature of the intermittent ultrasonic treatment is within the above range, excessive loss of low-boiling-point, volatile aromatic substances can be reduced or even avoided.

[0058] In some optional implementations, ultrasonic treatment is performed using an alternating 40Hz / 60Hz frequency. This dual-frequency ultrasonic treatment of the rice wine results in a superior sensory flavor.

[0059] In some embodiments, the duration of intermittent ultrasonic treatment is 7 days. This reduces the degradation of sensory flavor caused by excessively long ultrasonic treatment times. As one possible implementation, the raw materials for preparing the rice wine fermentation liquid include one or more of rice and wheat.

[0060] In some alternative embodiments, the rice wine fermentation liquid can be obtained by fermenting rice using rice wine fermentation processes commonly used in the art.

[0061] As a non-limiting example, the method for preparing the rice wine fermentation liquid is the traditional rice steaming method.

[0062] As an example, such as Figure 1 As shown, the methods for enhancing the flavor of Shaoxing wine include the following steps:

[0063] S1. Microwave heat treatment is performed on the distiller's grains; the microwave power is 600W-800W.

[0064] S2. The heat-treated lees are mixed with a complex protease and lactic acid bacteria and then fermented to prepare a flavor-enhancing liquid. The complex protease includes protease 1 and protease 2, protease 1 including a neutral protease and protease 2 including an acidic protease. The mass ratio of protease 1 to protease 2 is 1:1. The mass of the lactic acid bacteria is 1‰-1.5‰ of the mass of the heat-treated lees.

[0065] S3. Rice is used to ferment and prepare rice wine fermentation liquid. After mixing the flavor enhancement liquid with the rice wine fermentation liquid, proteinase 2 is added and subjected to intermittent ultrasonic treatment. After the intermittent ultrasonic treatment is completed, the mixture is stored and clarified.

[0066] One or more embodiments of this application provide a type of rice wine, which is obtained by treating the rice wine fermentation liquid using the above-described method for enhancing the flavor of rice wine.

[0067] The technical solutions of this application will be described in detail below with reference to specific embodiments. It should be understood that these embodiments are only for illustrating this application and are not intended to limit the scope of this application. For experimental methods in the following embodiments where specific conditions are not specified, please refer to the guidelines given in this application first, or follow experimental manuals or conventional conditions in the field, or follow the conditions recommended by the manufacturer, or refer to experimental methods known in the field.

[0068] In the specific embodiments described below, the measurement parameters involving raw material components may have slight deviations within the weighing accuracy range unless otherwise specified. Temperature and time parameters are subject to acceptable deviations due to instrument testing accuracy or operational precision.

[0069] It should be noted that the preparation method of the rice wine fermentation liquid in the following embodiments and comparative examples is the traditional rice steaming method.

[0070] In the following examples and comparative examples, "natural conditions" refers to the natural ambient temperature, which is 25°C.

[0071] In the following examples and comparative examples, protease 1 refers to a neutral protease and protease 2 refers to an acidic protease.

[0072] I. Preparation of Shaoxing Wine

[0073] Example 1

[0074] Step 1: Heat-treat the fermented rice wine lees in a microwave at 600W for 15 minutes. Add 10 ppm of protease 1, 10 ppm of protease 2, and 1‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 30℃ for 72 hours. After incubation, filter to obtain a clear liquid, and then place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0075] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 9:1 to obtain a mixed wine.

[0076] Step 3: Add 0.01 g / L of protease 2 to the mixed wine by volume.

[0077] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0078] Example 2

[0079] Step 1: Heat-treat the fermented rice wine lees in a microwave at 800W for 10 minutes. Add 15 ppm of protease 1, 15 ppm of protease 2, and 1.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid, and then place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0080] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 8:2 to obtain a mixed wine.

[0081] Step 3: Add 0.015 g / L of protease 2 to the mixed wine by volume.

[0082] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0083] Example 3

[0084] Step 1: Heat-treat the fermented rice wine lees in a microwave at 600W for 15 minutes. Add 10 ppm of protease 1, 10 ppm of protease 2, and 1‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 30℃ for 72 hours. After incubation, filter to obtain a clear liquid, and then place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0085] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 9:1 to obtain a mixed wine.

[0086] Step 3: Add 0.01 g / L of protease 2 to the mixed wine by volume.

[0087] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 80W, alternating between 40 / 60HZ for 10 minutes, ultrasonic temperature of 30℃, and ultrasonic treatment once every 12 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0088] Comparative Example 1

[0089] The rice wine fermentation liquid is stored under natural conditions for 6 months to obtain the rice wine product.

[0090] Comparative Example 2

[0091] Step 1: Heat-treat the fermented rice wine lees in a microwave at 400W for 20 minutes. Add 5 ppm of protease 1, 5 ppm of protease 2, and 0.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 30℃ for 72 hours. After incubation, filter to obtain a clear liquid and place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0092] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 7:3 to obtain a mixed wine.

[0093] Step 3: Add 0.03 g / L of protease 2 to the mixed wine by volume.

[0094] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0095] Comparative Example 3

[0096] The preparation method of Comparative Example 3 is similar to that of Example 2, except that the process parameters for the intermittent ultrasonic treatment in step 4 of Comparative Example 3 are different. Comparative Example 3 is detailed below:

[0097] Step 1: Heat-treat the fermented rice wine lees in a microwave at 800W for 10 minutes. Add 15 ppm of protease 1, 15 ppm of protease 2, and 1.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid, and then place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0098] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 8:2 to obtain a mixed wine.

[0099] Step 3: Add 0.015 g / L of protease 2 to the mixed wine by volume.

[0100] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 100W, alternating between 40 / 60HZ for 30 minutes, ultrasonic temperature of 30℃, and ultrasonic treatment once every 6 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0101] Comparative Example 4

[0102] The preparation method of Comparative Example 4 is similar to that of Example 2, except that: in Comparative Example 4, protease 2 was not added to the mixed wine, and the mixed wine was directly subjected to intermittent ultrasonic treatment. The details of Comparative Example 4 are as follows:

[0103] Step 1: Heat-treat the fermented rice wine lees in a microwave at 800W for 10 minutes. Add 15 ppm of protease 1, 15 ppm of protease 2, and 1.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid, and then place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0104] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 8:2 to obtain a mixed wine.

[0105] Step 3: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0106] Comparative Example 5

[0107] The preparation method of Comparative Example 5 is similar to that of Example 2, except that no flavor-enhancing liquid was added to the rice wine fermentation liquid in Comparative Example 5. Comparative Example 5 is detailed below:

[0108] Step 1: Add 0.015 g / L of protease 2 to the rice wine fermentation liquid based on its volume.

[0109] Step 2: Intermittently treat the rice wine fermentation liquid with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0110] Comparative Example 6

[0111] The preparation method of Comparative Example 6 is similar to that of Example 2, except that the mixed wine was not subjected to intermittent ultrasonic treatment in Comparative Example 6. Comparative Example 6 is detailed below:

[0112] Step 1: Heat-treat the fermented rice wine lees in a microwave at 800W for 10 minutes. Add 15 ppm of protease 1, 15 ppm of protease 2, and 1.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid, and then place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0113] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 8:2 to obtain a mixed wine.

[0114] Step 3: Add 0.015 g / L of protease 2 to the mixed wine by volume. Then let it stand under natural conditions for 6 months to obtain the rice wine product.

[0115] Comparative Example 7

[0116] The preparation method of Comparative Example 7 is similar to that of Example 2, except that the amount of protease 2 added in step 3 of Comparative Example 7 is 0.03 g / L. The details of Comparative Example 7 are as follows:

[0117] Step 1: Heat-treat the fermented rice wine lees in a microwave at 800W for 10 minutes. Add 15 ppm of protease 1, 15 ppm of protease 2, and 1.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid, and then place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0118] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 8:2 to obtain a mixed wine.

[0119] Step 3: Add 0.03 g / L of protease 2 to the mixed wine by volume.

[0120] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0121] Comparative Example 8

[0122] The preparation method of Comparative Example 8 is similar to that of Example 2, except that in step 2 of Comparative Example 8, the rice wine fermentation liquid and the flavor enhancement liquid are mixed at a mass ratio of 7:3. The details of Comparative Example 8 are as follows:

[0123] Step 1: Heat-treat the fermented rice wine lees in a microwave at 800W for 10 minutes. Add 15 ppm of protease 1, 15 ppm of protease 2, and 1.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times their weight of water. Stir well and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid, and then place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0124] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 7:3 to obtain a mixed wine.

[0125] Step 3: Add 0.015 g / L of protease 2 to the mixed wine by volume.

[0126] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0127] Comparative Example 9

[0128] The preparation method of Comparative Example 9 is similar to that of Example 2, except that microwave heat treatment of the yellowed distiller's grains was not used in step 1 of Comparative Example 9. The details of Comparative Example 9 are as follows:

[0129] Step 1: Add 15 ppm of protease 1, 15 ppm of protease 2, and 1.5‰ of lactic acid bacteria powder by weight of the fermented rice wine lees to the fermented rice wine lees. Add 1.5 times the weight of water, stir well, and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid, and place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0130] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 8:2 to obtain a mixed wine.

[0131] Step 3: Add 0.015 g / L of protease 2 to the mixed wine by volume.

[0132] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0133] Comparative Example 10

[0134] The preparation method of Comparative Example 10 is similar to that of Example 2, except that in step 1 of Comparative Example 10, protease 1 is used instead of protease 2. Comparative Example 10 is detailed below:

[0135] Step 1: Heat-treat the fermented rice wine lees in a microwave at 800W for 10 minutes. Add 30 ppm of protease 1 and 1.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times the weight of water. Stir well and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid and place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0136] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 8:2 to obtain a mixed wine.

[0137] Step 3: Add 0.015 g / L of protease 2 to the mixed wine by volume.

[0138] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0139] Comparative Example 11

[0140] The preparation method of Comparative Example 11 is similar to that of Example 2, except that in step 1 of Comparative Example 11, protease 2 is used instead of protease 1. The details of Comparative Example 11 are as follows:

[0141] Step 1: Heat-treat the fermented rice wine lees in a microwave at 800W for 10 minutes. Add 30 ppm of protease 2 and 1.5‰ of lactic acid bacteria powder by weight of the rice wine lees, along with 1.5 times the weight of water. Stir well and incubate at 37℃ for 48 hours. After incubation, filter to obtain a clear liquid and place it in an 80℃ water bath for 30 minutes to prepare the flavor-enhancing liquid.

[0142] Step 2: Mix the rice wine fermentation liquid and flavor enhancement liquid at a mass ratio of 8:2 to obtain a mixed wine.

[0143] Step 3: Add 0.015 g / L of protease 2 to the mixed wine by volume.

[0144] Step 4: Intermittently treat the mixed wine with ultrasound. The process parameters include: ultrasonic power of 60W, alternating between 40 / 60HZ for 15 minutes, ultrasonic temperature of 20℃, and ultrasonic treatment once every 24 hours for 7 days. Then, let it stand under natural conditions for 1 month to obtain the rice wine product.

[0145] II. Physicochemical Analysis

[0146] 1. The physicochemical analysis of the rice wine products obtained in Examples 1-3 and Comparative Examples 1-11 was performed using the following methods:

[0147] (1) Total acid, amino acid nitrogen, total ester: GB / T 17946-2008 Geographical Indication Product Shaoxing Wine (Shaoxing Yellow Wine).

[0148] (2) Turbidity: GB / T 5750.4-2023 Standard Test Methods for Drinking Water - Part 4: Sensory Characteristics and Physical Indicators.

[0149] (3) Ethyl lactate and volatile components: HP-5 MS column (30m×0.25 mm×0.25 μm), injection port temperature 250℃, initial temperature 40℃, held for 3.5 min, then increased to 90℃ at a rate of 5℃ / min, then increased to 230℃ at a rate of 6℃ / min, held for 2 min. The carrier gas was helium (He), with a flow rate of 1 mL / min. Mass spectrometry conditions: ion source temperature 230℃, ionization mode using electron ionization, electron energy 70 eV, scan range 33~450 m / z.

[0150] The physicochemical analysis results of Examples 1-3 and Comparative Examples 1-11 are shown in Table 1.

[0151] Table 1

[0152]

[0153] Comparison of the results of Example 2 with those of Comparative Examples 1 and 5 shows that after adding flavor-enhancing liquid to the rice wine fermentation liquid, the contents of total esters, ethyl lactate, total acid and amino acid nitrogen all increased significantly, and the flavor components of rice wine increased significantly.

[0154] A comparison of the results of Example 2 with those of Comparative Examples 2 and 8 shows that, compared to Example 2, the total acid content in the comparative examples exceeds the national standard for rice wine. Although the ethyl lactate content increased in the comparative examples, the total ester content decreased; this may be due to the excessively high proportion of flavor-enhancing liquid added, which diluted the proportion of alcohol substrates in the esterification reaction, thus resulting in a decrease in the total ester content.

[0155] A comparison of the results of Example 2 with those of Comparative Examples 1 and 6 shows that the total ester content of the rice wine is higher after ultrasonic treatment compared to natural storage. A comparison of the results of Example 2 with those of Comparative Example 3 shows that the total ester content in Comparative Example 3 shows a decreasing trend; this may be because excessive ultrasonic treatment causes the reverse reaction rate of the esterification reaction to exceed the forward reaction rate, thus accelerating the decomposition of esters.

[0156] A comparison of the results from Example 2 and Comparative Example 4 shows that when the rice wine fermentation liquid and flavor-enhancing liquid are mixed and then subjected to intermittent ultrasonic treatment, the addition of protease further degrades the protein macromolecules, significantly reducing the turbidity of the rice wine product and avoiding the influence of lees on the product's appearance. A comparison of the results from Example 2 with Comparative Examples 2 and 7 shows that adding excessive amounts of protease limits the effect of improving the appearance of the rice wine and carries the risk of introducing new proteins into the rice wine.

[0157] The comparison between the results of Example 2 and Comparative Example 9 shows that after heat treatment of the lees in Example 2, the contents of total esters, ethyl lactate, total acid and amino acid nitrogen in the rice wine all increased, and the flavor components of the rice wine increased significantly. This indicates that heat treatment of the lees by microwave destroys the protein structure, which is beneficial to proteolysis and lactic acid bacteria fermentation.

[0158] The comparison between the results of Example 2 and Comparative Examples 10-11 shows that the fermentation treatment using compound protease in Example 2 resulted in an increase in the total ester, ethyl lactate, total acid, and amino acid nitrogen content of the rice wine, and a significant increase in the flavor components of the rice wine. This indicates that the fermentation treatment using compound protease can effectively degrade proteins in the lees and produce more flavor substrates.

[0159] 2. The volatile components and contents of the rice wine products obtained in Example 2 and Comparative Example 1 were determined, and the results are as follows: Figure 2 As shown.

[0160] Depend on Figure 2 It can be seen that after ultrasonic treatment, the content of floral and fruity aroma components and nutty aroma components in rice wine with added flavor-enhancing liquid is significantly increased, and new flavor substances are generated, making the overall flavor of rice wine stronger and richer.

[0161] In summary, the method for enhancing the flavor of Shaoxing wine provided in this application utilizes Shaoxing wine lees to prepare a flavor-enhancing liquid, combined with ultrasonic treatment, which significantly increases the flavor compounds in the Shaoxing wine, resulting in a stronger and richer overall flavor. Furthermore, the addition of protease further breaks down large molecules in the wine, avoiding the impact of lees on the product's turbidity and improving the overall appearance of the Shaoxing wine. This process is simple to operate and meets production requirements.

[0162] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0163] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for enhancing the flavor of Shaoxing wine, characterized in that, Includes the following steps: Microwave heat treatment is used to treat the distiller's grains; The heat-treated lees are mixed with a complex protease and lactic acid bacteria and then fermented to prepare a flavor-enhancing liquid. The complex protease includes protease 1 and protease 2. Protease 1 includes a neutral protease and protease 2 includes an acidic protease. The flavor-enhancing liquid is mixed with the rice wine fermentation liquid to prepare a mixed wine, wherein the mass ratio of the rice wine fermentation liquid to the flavor-enhancing liquid is 8:2-9:

1. The mixed wine and the protease 2 were mixed and subjected to intermittent ultrasonic treatment to accelerate the generation of flavor substances in the rice wine. The amount of protease 2 added was 0.01g / L-0.015g / L based on the volume of the mixed wine. The process parameters of the intermittent ultrasonic treatment included: ultrasonic power of 60W-80W, ultrasonic treatment once every 12h-24h, and ultrasonic treatment time of 10min-15min each time.

2. The method for enhancing the flavor of rice wine as described in claim 1, characterized in that, The power of the microwave is 600W-800W.

3. The method for enhancing the flavor of rice wine as described in claim 1, characterized in that, The heat treatment time is 10-15 minutes.

4. The method for enhancing the flavor of rice wine as described in claim 1, characterized in that, The mass of the complex protease is 10 ppm-15 ppm of the mass of the heat-treated distiller's grains; and / or, The mass ratio of protease 1 to protease 2 in the complex protease is 1:

1.

5. The method for enhancing the flavor of rice wine as described in claim 1, characterized in that, The mass of the lactic acid bacteria is 1‰-1.5‰ of the mass of the heat-treated distiller's grains.

6. The method for enhancing the flavor of rice wine as described in claim 1, characterized in that, The fermentation treatment temperature is 30℃-37℃, and the time is 48h-72h.

7. The method for enhancing the flavor of rice wine as described in claim 1, characterized in that, The temperature for intermittent ultrasonic treatment is 20℃-30℃.

8. The method for enhancing the flavor of rice wine as described in claim 1, characterized in that, The duration of the intermittent ultrasonic treatment was 7 days.

9. The method for enhancing the flavor of rice wine as described in any one of claims 1 to 8, characterized in that, The raw materials for preparing the rice wine fermentation liquid include one or more of rice and wheat.

10. A type of rice wine, characterized in that, The rice wine fermentation liquid is obtained by treating it with the method for enhancing the flavor of rice wine as described in any one of claims 1 to 9.

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