Preparation method for brewing Xueqing pear wine through double-bacterium fermentation

Abstract

The invention belongs to the technical field of wine brewing, and particularly relates to a preparation method for brewing Xueqing pear wine through double-bacterium fermentation. The preparation method comprises the following steps: S1, removing kernels from ripe Xueqing pear fruits, cutting into small blocks, juicing, and filtering to obtain pear juice; s2, adding pectinase into the pear juice in the S1, performing enzymolysis at room temperature, and then adding white granulated sugar into the pear juice to adjust the sugar degree and the pH value; s3, carrying out SO2 color protection treatment, and adjusting the concentration of SO2 in the filtrate to obtain pear juice; the method comprises the following steps: sequentially adding non-saccharomyces cerevisiae NS-D and saccharomyces cerevisiae VL-2 into pear wine, activating, and inoculating to obtain fermentation liquor; s4, fermenting the fermentation liquid obtained in S3 to obtain a finished product of Xueqing pear wine, and adjusting the fermented Xueqing pear wine to obtain the Xueqing pear wine brewed by double-bacterium fermentation.

Description

Technical Field

[0001] The present invention belongs to the technical field of winemaking, and particularly relates to a preparation method for brewing Xueqing pear wine by double-strain fermentation. Background Art

[0002] Fruit wine is a special beverage made from fresh fruits. After pressing to extract juice, it is inoculated with Saccharomyces cerevisiae for alcoholic fermentation. As a typical healthy drink, fruit wine not only has a relatively low alcohol content but also is rich in various nutrients and has unique flavor characteristics.

[0003] Currently, the brewing of pear wine mostly follows the process paradigm of wine, fermenting with a single Saccharomyces cerevisiae, which has significant disadvantages, mainly reflected in flavor levels and biological stability. The metabolic pathway is single, which may lead to flat aroma in pear wine, lack of three-dimensional sense of fruity and aged aromas. Secondly, the environmental adaptability of a single strain is weak. When the components of pear juice (such as pH, sugar-acid ratio) fluctuate, it is easy to cause fermentation stagnation or abnormal metabolism, and the ability to resist contamination by miscellaneous bacteria is poor, which may produce off-flavor substances such as hydrogen sulfide. In addition, it cannot fully decompose specific carbohydrate substances in pear fruits, which may affect the clarity of the wine body and the smoothness of the taste. This fermentation method is difficult to display the unique flavor characteristics of different pear varieties and limits the flavor diversity of products. However, the mixed fermentation of Saccharomyces cerevisiae and non-Saccharomyces cerevisiae can significantly improve the quality and process stability of pear wine. First, the metabolic complementarity is enhanced: non-Saccharomyces cerevisiae can secrete extracellular enzymes to decompose polysaccharides and terpene glycosides in pear fruits, releasing precursors of floral and fruity aromas, while Saccharomyces cerevisiae dominates alcohol production. The two work together to expand the flavor dimension, forming richer esters, terpenes, and volatile phenols. Secondly, the biological barrier effect reduces the risk of contamination: non-Saccharomyces cerevisiae rapidly proliferates and consumes oxygen in the initial stage of fermentation, inhibiting the growth of miscellaneous bacteria. At the same time, substances such as antibacterial peptides produced by its metabolism can enhance the stress resistance of the system. In addition, the two strains reduce the accumulation of bad by-products such as hydrogen sulfide through metabolic division of labor, improving the purity of the wine body. Mixed fermentation can also adapt to a wider range of pH and sugar concentrations, improving the utilization rate of raw materials. The final product has a complex aroma structure, delicate taste, and the potential to express regional terroir, providing more possibilities for the flavor innovation of pear wine. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a preparation method for brewing Xueqing pear wine by double-strain fermentation, which can increase the acidity of Xueqing pear wine, improve the aroma of Xueqing pear wine, and enhance the biological stability of Xueqing pear wine. The brewed Xueqing pear wine has the unique flavor of pear wine, completely retains the elegant fruity aroma characteristics of Xueqing pears, the wine body presents an amber luster, is smooth and mellow in the mouth with a round acidity, and has a pure fruity aroma.

[0005] To solve the above technical problems, the present invention provides a preparation method for brewing Xueqing pear wine by double-strain fermentation, including the following steps:

[0006] S1: Cut the mature Xueqing pear fruits into small pieces after removing the pits, juice them and then filter to obtain pear juice;

[0007] S2: Add pectinase to the pear juice in S1, enzymatically hydrolyze it at room temperature, and then add granulated sugar to the pear juice to adjust the sugar content and pH;

[0008] S3: Conduct SO2 color protection treatment, adjust the concentration of SO2 in the filtrate to obtain pear juice; sequentially add non - Saccharomyces yeast NS - D to the pear wine, and then add Saccharomyces cerevisiae VL - 2, and then activate it. After activation, inoculate to obtain the fermentation broth;

[0009] S4: Ferment the fermentation broth obtained in S3 to obtain the finished Xueqing pear wine, and adjust the fermented Xueqing pear wine to obtain the Xueqing pear wine brewed by double - strain fermentation.

[0010] Further, the addition amount of the pectinase described in S2 is 30 mg / L, and the enzymatic hydrolysis time is 30 min.

[0011] Further, the sugar content during the process of adjusting the sugar content described in S2 is 20 - 24 °Brix; the pH is 3.3 - 3.7.

[0012] Further, the SO2 concentration described in S3 is 60 mg / L.

[0013] Further, the inoculation method described in S3 is sequential inoculation, and the total amount of added strains is 0.5 g / L; the activation temperature is 37 °C, and the activation time is 30 min.

[0014] Further, the mass ratio of non - Saccharomyces yeast to Saccharomyces cerevisiae described in S3 is 2 - 1:1 - 2; the inoculation process is inoculated at an interval of 48 h.

[0015] Further, the fermentation time described in S4 is 12 days, and the fermentation temperature is 24 - 28 °C.

[0016] Beneficial effects

[0017] The preparation method of the Xueqing pear wine brewed by double - strain fermentation provided by the present invention can increase the nutrient substances of the Xueqing pear wine, improve the aroma of the Xueqing pear wine, and improve the biological stability of the Xueqing pear wine. The brewed Xueqing pear wine has the unique flavor of the Xueqing pear wine, completely retains the elegant fruity aroma characteristics of the Xueqing pear, the wine body presents an amber luster, is smooth in the mouth and has a mellow acidity, and the fruity aroma is pure.

[0018] The present invention first adopts sequential inoculation for alcoholic fermentation, first uses the domestic Angel yeast NS - D non - Saccharomyces yeast strain, and then uses the French VL - 2 Saccharomyces cerevisiae. This not only increases the content of phenolic substances in the Xueqing pear wine, but also increases the free aroma substances in the Xueqing pear wine. The brewed Xueqing pear wine has a mellow sour taste, increases its biological stability, and has a pure wine aroma. Specific Embodiments

[0019] Next, in combination with Embodiments 1-10 of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0020] The present invention provides a preparation method for brewing Xueqing pear wine by double-strain fermentation, including the following steps:

[0021] S1: First, prepare pear juice. Select fresh, pest-free, and non-rotten mature Xueqing pear fruits, wash the Xueqing pears, cut them into small pieces after removing the cores, juice them, and then filter to obtain pear juice;

[0022] S2: Add pectinase to the pear juice and perform enzymatic hydrolysis treatment at room temperature. Add granulated sugar to the pear juice to adjust the sugar content;

[0023] S3: Filter the pear juice in S2, adjust the SO2 concentration in the filtrate, perform SO2 color protection treatment to obtain pear juice; perform strain inoculation and activation. First, add non-Saccharomyces cerevisiae NS-D, and then add Saccharomyces cerevisiae VL-2. The non-Saccharomyces cerevisiae and Saccharomyces cerevisiae are inoculated into the pear juice at intervals of 48 hours successively to obtain the fermentation broth;

[0024] S4: Place the fermentation broth in an incubator for fermentation. After 12 days of fermentation, take out the fermentation tank to obtain the finished Xueqing pear wine. Adjust the SO2 concentration in the fermented Xueqing pear wine, stop fermentation, and perform centrifugal filtration to obtain the fermented Xueqing pear wine.

[0025] Embodiment 1:

[0026] S1: Select fresh, pest-free, and non-rotten mature Xueqing pear fruits, wash the Xueqing pears, cut them into small pieces after removing the cores, juice them, and then filter to obtain pear juice;

[0027] S2: Add pectinase to the pear juice, with an addition amount of 30 mg / L, and perform enzymatic hydrolysis for 30 minutes at room temperature; add granulated sugar to the pear juice to adjust the sugar content to 22 °Brix and adjust the pH to 3.5;

[0028] S3: Adjust the SO2 concentration in the filtrate to 60 mg / L to obtain pear juice, then inoculate and activate the strains. The inoculation method is sequential inoculation. The total amount of strains added to the pear wine is 0.5 g / L. First, add non-Saccharomyces yeast NS-D, and then add Saccharomyces cerevisiae VL-2. After activating at 37 °C for 30 min, inoculate. Inoculate into the pear juice at intervals of 48 h in the ratio of non-Saccharomyces yeast:Saccharomyces cerevisiae of 1:1 to obtain the fermentation broth;

[0029] S4: Place the fermentation broth in an incubator for fermentation. After fermenting for 12 d at 24 °C, take out the fermenter to obtain the finished Xueqing pear wine; Add SO2 to the fermented Xueqing pear wine, and the addition amount is 60 mg / L to stop the fermentation. After centrifugal filtration, the fermented Xueqing pear wine is obtained.

[0030] Example 2

[0031] S1: The same as in Example 1;

[0032] S2: Adjust the sugar degree to 20 °Brix and the pH to 3.3, and the remaining steps are the same;

[0033] S3: The ratio of non-Saccharomyces yeast:Saccharomyces cerevisiae is 2:1, and the remaining steps are the same;

[0034] S4: The fermentation temperature is 24 °C, and the remaining steps are the same.

[0035] Example 3

[0036] S1: The same as in Example 1;

[0037] S2: Adjust the sugar degree to 22 °Brix and the pH to 3.5, and the remaining steps are the same;

[0038] S3: The ratio of non-Saccharomyces yeast:Saccharomyces cerevisiae is 1:1, and the remaining steps are the same;

[0039] S4: The fermentation temperature is 24 °C, and the remaining steps are the same.

[0040] Example 4

[0041] S1: The same as in Example 1;

[0042] S2: Adjust the sugar degree to 24 °Brix and the pH to 3.7, and the remaining steps are the same;

[0043] S3: The ratio of non-Saccharomyces yeast:Saccharomyces cerevisiae is 1:2, and the remaining steps are the same;

[0044] S4: The fermentation temperature is 24 °C, and the remaining steps are the same.

[0045] Example 5

[0046] S1: The same as in Example 1;

[0047] S2: The sugar content is adjusted to 20 °Brix and the pH is 3.3, and the remaining steps are the same;

[0048] S3: The ratio of non - Saccharomyces cerevisiae to Saccharomyces cerevisiae is 1:1, and the remaining steps are the same;

[0049] S4: The fermentation temperature is 26 °C, and the remaining steps are the same.

[0050] Example 6

[0051] S1: The same as in Example 1;

[0052] S2: The sugar content is adjusted to 22 °Brix and the pH is 3.5, and the remaining steps are the same;

[0053] S3: The ratio of non - Saccharomyces cerevisiae to Saccharomyces cerevisiae is : 2, and the remaining steps are the same;

[0054] S4: The fermentation temperature is 26 °C, and the remaining steps are the same.

[0055] Example 7

[0056] S1: The same as in Example 1;

[0057] S2: The sugar content is adjusted to 24 °Brix and the pH is 3.7, and the remaining steps are the same;

[0058] S3: The ratio of non - Saccharomyces cerevisiae to Saccharomyces cerevisiae is 2:1, and the remaining steps are the same;

[0059] S4: The fermentation temperature is 26 °C, and the remaining steps are the same.

[0060] Example 8

[0061] S1: The same as in Example 1;

[0062] S2: The sugar content is adjusted to 20 °Brix and the pH is 3.3, and the remaining steps are the same;

[0063] S3: The ratio of non - Saccharomyces cerevisiae to Saccharomyces cerevisiae is 1:2, and the remaining steps are the same;

[0064] S4: The fermentation temperature is 28 °C, and the remaining steps are the same.

[0065] Example 9

[0066] S1: The same as in Example 1;

[0067] S2: The sugar content is adjusted to 22 °Brix and the pH is 3.5, and the remaining steps are the same;

[0068] S3: The ratio of non - Saccharomyces cerevisiae to Saccharomyces cerevisiae is 2:1, and the remaining steps are the same;

[0069] S4: The fermentation temperature is 28 °C, and the remaining steps are the same.

[0070] Example 10

[0071] S1: The same as in Example 1;

[0072] S2: The sugar degree is adjusted to 24 °Brix and the pH is 3.7, and the remaining steps are the same;

[0073] S3: The ratio of non - Saccharomyces cerevisiae to Saccharomyces cerevisiae is 1:1, and the remaining steps are the same;

[0074] S4: The fermentation temperature is 28 °C, and the remaining steps are the same.

[0075] The Xueqing pear wine obtained from Examples 1 - 10 was subjected to sensory evaluation.

[0076] The present invention provides a preparation method for brewing Xueqing pear wine by double - strain fermentation. By sequentially inoculating two yeast strains, this preparation method significantly improves the nutritional components and aroma characteristics of Xueqing pear wine, while enhancing its biological stability. Specifically, domestic Angel yeast NS - D non - Saccharomyces cerevisiae is used for preliminary alcoholic fermentation, and then French VL - 2 Saccharomyces cerevisiae is inoculated, which not only increases the content of phenolic substances in Xueqing pear wine, but also promotes the release of aroma substances. The finally brewed Xueqing pear wine fully retains the elegant fruity aroma of Xueqing pears. The wine body is amber - colored, with a smooth taste, a mellow acidity, a pure fruity aroma, and a pure and mellow wine aroma. It has excellent biological stability and exhibits a unique flavor.

Claims

1. A preparation method of Xueqing pear wine brewed by double-bacteria fermentation, characterized in that, It includes the following steps: S1: Cut the mature Xueqing pear fruits into small pieces after removing the cores, juice them and filter to obtain pear juice; S2: Add pectinase to the pear juice in S1, enzymatically hydrolyze it at room temperature, and then add granulated sugar to the pear juice to adjust the sugar content and pH; S3: Perform SO2 color protection treatment, adjust the concentration of SO2 in the filtrate to obtain pear juice; sequentially add non-Saccharomyces cerevisiae NS-D to the pear wine, and then add Saccharomyces cerevisiae VL-2, and then activate it. After activation, inoculate to obtain the fermentation broth; S4: Ferment the fermentation broth obtained in S3 to obtain the finished Xueqing pear wine, and adjust the fermented Xueqing pear wine to obtain the Xueqing pear wine brewed by double-strain fermentation.

2. The preparation method of a double-fermented Xueqing pear wine according to claim 1, characterized in that, The addition amount of the pectinase described in S2 is 30 mg / L, and the enzymatic hydrolysis time is 30 min.

3. The preparation method of a double-fermentation brewed Xueqing pear wine according to claim 1, characterized in that, The sugar content during the process of adjusting the sugar content described in S2 is 20-24 °Brix; the pH is 3.3-3.

7.

4. The preparation method of a double-fermented Xueqing pear wine according to claim 1, characterized in that, The SO2 concentration described in S3 is 60 mg / L.

5. The preparation method of a double-fermentation brewed Xueqing pear wine according to claim 1, characterized in that, The inoculation method described in S3 is sequential inoculation, and the total amount of added strains is 0.5 g / L; the activation temperature is 37 °C, and the activation time is 30 min.

6. The preparation method of a double-fermentation brewed Xueqing pear wine according to claim 1, characterized in that, The mass ratio of non-Saccharomyces cerevisiae to Saccharomyces cerevisiae described in S3 is 2-1:1-2; the inoculation process is inoculated at intervals of 48 h.

7. The preparation method of a double-fermented Xueqing pear wine according to claim 1, characterized in that, The fermentation time described in S4 is 12 days, and the fermentation temperature is 24-28 °C.