Treatment method of grape wine and preparation method of grape distilled wine

Abstract

The invention belongs to the technical field of fruit wine, and particularly relates to a treatment method of grape wine and a preparation method of grape distilled wine. The method comprises the following steps: carrying out membrane separation on grape wine by adopting a nanofiltration membrane to obtain permeate and concentrated grape wine; mixing the permeate liquid with alkaline substances allowed to be used in GB2760 to obtain alkali treatment permeate liquid; according to the method, a nanofiltration membrane separation and alkali treatment combined method is adopted, sulfur dioxide in the raw material wine can be effectively changed into combined salt without volatility, so that sulfur dioxide is not brought into the grape distilled wine along with ethanol and the like any more, equipment corrosion and bad flavor generation are avoided, and the quality of the grape distilled wine is improved; meanwhile, after the wine is subjected to nanofiltration membrane separation, the ageing potential of a concentrated product which does not penetrate through the membrane is further improved due to the characteristics of deep color, high acidity, tannin content and the like, and the concentrated product can be used for blending normal wine products.

Description

Technical Field

[0001] The invention belongs to the technical field of fruit wine, and in particular relates to a method for processing wine and a method for preparing grape distilled wine. Background Art

[0002] Grape distilled spirits are a major product category within the wine industry. Over the past decade, the wine industry has entered a period of adjustment, with slow sales. This has led to a significant backlog of wine (unbottled wine in cans) being distilled and used to produce grape distilled spirits, further enriching the product range, saving tank capacity, and improving product storability and value-added potential.

[0003] In addition to wine without added sulfur dioxide being used to produce grape distilled spirits, wine with added sulfur dioxide is also widely used in the production of grape distilled spirits. Before using wine containing sulfur dioxide as a raw material for distillation, the traditional method is to use hydrogen peroxide (H2O2), a processing aid permitted by GB2760, to react with the sulfur dioxide in the wine, oxidizing it into non-volatile sulfuric acid and its salts, which are not introduced into the grape distilled spirit during distillation. This prevents sulfur dioxide from being introduced into the grape distilled spirit during distillation and creating unpleasant flavors during the distillation process, ultimately affecting the quality of the distilled spirit and causing corrosion to the equipment.

[0004] Currently, GB2760 no longer considers hydrogen peroxide as a processing aid that can be used in this field (GB2760-2024, implemented on February 8, 2025). At the same time, in the previous treatment process using hydrogen peroxide, it also showed oxidative damage to the aroma, pigments, tannins, etc. of wine, making it impossible to effectively collect and utilize pigments and tannins, resulting in a lot of waste and low utilization rate of wine raw materials. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for processing wine and a method for preparing grape distilled liquor. The present invention adopts a method that meets the requirements of GB2760-2024 to effectively remove sulfur dioxide from wine, prevent sulfur dioxide from being introduced into the grape distilled liquor, and improve the quality of the grape distilled liquor; at the same time, the concentrated wine obtained can be reused, thereby improving the utilization rate of wine raw materials.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides a wine processing method, comprising the following steps:

[0008] The wine is subjected to membrane separation using a nanofiltration membrane to obtain a permeate and concentrated wine, wherein the wine contains sulfur dioxide;

[0009] The permeate is mixed with an alkaline substance permitted for use in GB2760 to obtain an alkali-treated permeate.

[0010] Preferably, the pore size of the nanofiltration membrane is 0.5 to 2 nm.

[0011] Preferably, the nanofiltration membrane is a polyamide composite nanofiltration membrane; the membrane structure of the nanofiltration membrane is a roll membrane.

[0012] Preferably, the temperature of the membrane separation is 5 to 25°C.

[0013] Preferably, the membrane surface flow rate of the nanofiltration membrane during membrane separation is 0.1 to 2 m / s;

[0014] During the membrane separation, the transmembrane pressure difference of the nanofiltration membrane is 0 to 2.5 MPa and is not zero.

[0015] Preferably, in the wine, the free SO2 content is 18-20 mg / L, the total SO2 content is 105-110 mg / L, the total acid content is 4-5 g / L, and the pH value is 3-4.

[0016] Preferably, in the permeate, the free SO2 content is 12-15 mg / L, the total SO2 content is 50-54 mg / L, the total acid content is 3-3.3 g / L, and the pH value is 3-4.

[0017] Preferably, in the concentrated wine, the free SO2 content is 20-23 mg / L, the total SO2 content is 150-160 mg / L, the total acid content is 5.5-6 g / L, and the pH value is 3-4.

[0018] Preferably, the alkaline substance includes one or more of sodium carbonate, sodium hydroxide and sodium bicarbonate;

[0019] The pH value of the alkali-treated permeate is ≥6.

[0020] The present invention provides a method for preparing grape distilled wine, comprising the following steps:

[0021] Alkali-treated permeate obtained by the treatment method described in the above technical solution;

[0022] The alkali-treated permeate is used as a raw material for preparing the grape distilled wine.

[0023] The present invention provides a wine processing method, comprising the following steps: subjecting the wine to membrane separation using a nanofiltration membrane to obtain a permeate and concentrated wine, wherein the wine is wine containing sulfur dioxide; and mixing the permeate with an alkaline substance permitted for use in GB2760 to obtain an alkali-treated permeate. The present invention utilizes a combined method of nanofiltration membrane separation and alkali treatment. In the first step, the wine is subjected to nanofiltration membrane separation to maximize the retention of organic acids (including tartaric acid), tannins, pigments, sugars, and other substances in the wine, while the permeate is an alcohol-water solution rich in aroma substances that readily permeate the membrane. In the second step, the permeate is subjected to an alkali treatment (i.e., an acid-base reaction) using an alkaline substance permitted for use in GB2760. The sulfur dioxide in the obtained alkali-treated permeate is converted to bound sulfate. Due to its non-volatility, no sulfur dioxide enters the grape distilled wine during distillation of the alkali-treated permeate to prepare the distilled wine. The concentrated wine produced in the first step that does not pass through the membrane has further enhanced aging potential due to its darker color, higher acidity and tannin content, and can be used for the blending of normal wine products. Compared with the raw material processing method during traditional distillation, the concentrated wine obtained by the present invention can be further utilized, thereby effectively improving the utilization rate of raw materials. In summary, the present invention uses a method that meets the requirements of GB2760-2024 to effectively remove sulfur dioxide from wine, prevent sulfur dioxide from being introduced into grape distilled wine, and improve the quality of grape distilled wine; at the same time, the concentrated wine obtained can be reused, thereby improving the utilization rate of wine raw materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of a device for membrane separation of wine using a nanofiltration membrane in an embodiment of the present invention;

[0025] In the figure: 1 is a raw material tank, 2 is a heat exchanger, 3 is a circulation pump, 4 is a nanofiltration membrane, 5 is a pressure gauge, 6 is a flow meter, 7 is a thermometer, and 8 is a permeate outlet. DETAILED DESCRIPTION

[0026] The present invention provides a wine processing method, comprising the following steps:

[0027] The wine is subjected to membrane separation using a nanofiltration membrane to obtain a permeate and concentrated wine, wherein the wine contains sulfur dioxide;

[0028] The permeate is mixed with an alkaline substance permitted for use in GB2760 to obtain an alkali-treated permeate.

[0029] In the present invention, unless otherwise specified, all preparation raw materials / components are commercially available products well known to those skilled in the art.

[0030] The present invention uses a nanofiltration membrane to separate wine to obtain a permeate and concentrated wine. The wine contains sulfur dioxide. In the present invention, the wine contains sulfur dioxide. The sulfur dioxide in the wine exists in both bound and free forms. In the present invention, the wine (i.e., the key physical and chemical indicators of the wine) includes: a free SO2 content of preferably 18-20 mg / L, and in the embodiment, 18 mg / L; a total SO2 content of preferably 105-110 mg / L, and in the embodiment, 105 mg / L; a total acid content of preferably 4-5 g / L, and in the embodiment, 4.4 g / L; and a pH of preferably 3-4, and in the embodiment, 3.76. The key physical and chemical indicators of the wine also preferably include alcohol content, which is preferably 12-13% (v / v), and in the embodiment, 12.5% ​​(v / v).

[0031] In the present invention, the nanofiltration membrane is preferably a polyamide composite nanofiltration membrane; the membrane structure of the nanofiltration membrane is preferably a spiral membrane; and the pore size of the nanofiltration membrane is preferably 0.5 to 2 nm, more preferably 1 to 1.5 nm.

[0032] In the present invention, the temperature of the membrane separation is preferably 5 to 25°C, more preferably 15 to 20°C, and in the embodiment, it can be 25°C. The membrane surface flow rate of the nanofiltration membrane during the membrane separation is preferably 0.1 to 2 m / s, more preferably 0.5 to 1.5 m / s; the transmembrane pressure difference of the nanofiltration membrane during the membrane separation is preferably 0 to 2.5 MPa, and is not 0, more preferably 0.2 to 2 MPa, further preferably 0.5 to 1.5 MPa, and in the embodiment, it can be 2 MPa. The present invention preferably achieves more effective separation of organic acids (including tartaric acid), tannins, pigments, sugars and other substances in (i.e., raw wine) and complexed sulfur by controlling the above-mentioned operating parameters of the membrane separation.

[0033] In the present invention, after obtaining the permeate, the pH, total acid content, and sulfur dioxide content of the permeate are preferably measured. The permeate (i.e., key physical and chemical indicators of the permeate) preferably includes: free SO2 content of 12-15 mg / L, preferably 15 mg / L in the embodiment; total SO2 content of 50-54 mg / L, preferably 54 mg / L in the embodiment; total acid content of 3-3.3 g / L, preferably 3.3 g / L in the embodiment; and pH of 3-4, preferably 3.81 in the embodiment. Key physical and chemical indicators of the permeate also preferably include alcohol content, which is preferably 12-13% (v / v), and can be 12.3% (v / v) in the embodiment.

[0034] In the present invention, the concentrated wine (i.e., the key physical and chemical indicators of the concentrated wine) preferably has the following characteristics: free SO2 content is preferably 20-23 mg / L, and in the embodiment, it is 23 mg / L; total SO2 content is preferably 150-160 mg / L, and in the embodiment, it is 160 mg / L; total acid content is preferably 5.5-6 g / L, and in the embodiment, it is 5.6 g / L; pH value is preferably 3-4, and in the embodiment, it is 3.73. The key physical and chemical indicators of the concentrated wine also preferably include alcohol content, which is preferably 12-13% (v / v), and in the embodiment, it can be 12.3% (v / v).

[0035] In the present invention, the volume of the permeate obtained by membrane separation using the nanofiltration membrane preferably accounts for 70-80% of the total volume of the wine. The volume of the concentrated wine obtained by membrane separation using the nanofiltration membrane preferably accounts for 20-30% of the total volume of the wine.

[0036] This invention uses nanofiltration membranes for wine separation, effectively separating active ingredients such as organic acids (including tartaric acid), tannins, and pigments into concentrated wine, allowing the resulting concentrated wine to be reused. Furthermore, nanofiltration membrane separation can intercept bound sulfur dioxide in the wine, allowing the resulting permeate to be redistilled to produce grape distilled wine, resulting in a cleaner, purer aroma.

[0037] The schematic diagram of the device structure for separating wine by nanofiltration membrane is shown in the following figure: Figure 1 As shown below, combined Figure 1 The specific embodiment of the present invention using a nanofiltration membrane for membrane separation of wine will be described in detail. The wine is stored in a raw material tank 1, enters a heat exchanger 2 via a circulation pump 3 for heat exchange, and then enters a nanofiltration membrane 4 for membrane separation. Permeate is obtained at the permeate outlet 8 of the nanofiltration membrane 4, and concentrated wine is obtained at the concentrate outlet of the nanofiltration membrane. The concentrated wine is then circulated back into the raw material tank 1. A pressure gauge 5 and a flow meter 6 are preferably installed on the pipeline leading to the concentrate outlet of the nanofiltration membrane 4. The raw material tank is also preferably equipped with a thermometer 7.

[0038] In the present invention, the temperature of the wine increases as it is pumped by the circulation pump. The heat exchanger can adjust the temperature of the wine to meet the membrane separation temperature. That is, the temperature of the wine after heat exchange by the heat exchanger (i.e., the membrane separation temperature) is preferably 5-25°C, more preferably 15-20°C.

[0039] After obtaining the permeate, the present invention mixes the permeate with an alkaline substance permitted for use in GB2760 to obtain an alkali-treated permeate. In the present invention, the alkaline substance is preferably a water-soluble alkaline substance. The alkaline substance preferably includes one or more of sodium carbonate, sodium hydroxide, and sodium bicarbonate, and in the embodiment, sodium carbonate. In the present invention, the alkaline substance is preferably used in the form of an aqueous alkaline solution, and the mass concentration of the alkaline substance in the aqueous alkaline solution is preferably 150 to 180 g / L. In the present invention, the alkaline substance is preferably mixed by online addition. The pH value of the alkali-treated permeate is preferably ≥ 6, and more preferably 6 to 7.

[0040] The present invention provides a method for preparing grape distilled wine, comprising the following steps:

[0041] Alkali-treated permeate obtained by the treatment method described in the above technical solution;

[0042] The alkali-treated permeate is used as a raw material for preparing the grape distilled wine.

[0043] The present invention adopts the alkali-treated permeate obtained by the treatment method described in the above technical solution.

[0044] After obtaining the alkali-treated permeate, the present invention uses the alkali-treated permeate as a raw material for preparing the grape distilled wine. In the present invention, when the alkali-treated permeate is used as a raw material for preparing the grape distilled wine, the grape distilled wine is preferably prepared by distillation, preferably continuous distillation, and preferably using a continuous tower distillation method. The tower bottom temperature during distillation is preferably 103-105°C, and the distillation is preferably atmospheric distillation.

[0045] In summary, the wine processing method provided by the present invention performs nanofiltration membrane separation and filtration on the wine, and the obtained concentrated wine contains organic acids (including tartaric acid), tannins and plain color, which can be reused without causing waste of raw materials; then, an alkaline substance permitted by GB2760 is used to react with the acid (including sulfur dioxide) in the permeate, so that the sulfur dioxide in the permeate is converted into a bound sulfate, and the sulfur dioxide is converted into a non-volatile salt, effectively preventing the sulfur dioxide from entering the grape distilled wine.

[0046] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0047] Example 1:

[0048] This embodiment provides a method for processing wine, which specifically includes the following steps:

[0049] (1) Nanofiltration membrane separation and filtration of wine

[0050] The key physical and chemical indicators of the wine (original wine) treated in this embodiment are shown in Table 1. Figure 1 The schematic diagram of the device shown shows membrane separation of wine. Wine flows from the raw material tank via a circulation pump into a heat exchanger for heat exchange, and then is transported to a nanofiltration membrane for separation. The nanofiltration membrane is a polyamide composite nanofiltration membrane with a spiral wound structure and a pore size of 1 to 1.5 nm. The membrane separation temperature is 25°C, the flow rate across the membrane surface is 1.5 m / s, and the transmembrane pressure difference is 2 MPa. Permeate is obtained from the permeate outlet of the nanofiltration membrane, and concentrated wine is obtained from the concentrate outlet. The concentrated wine is circulated back to the raw material tank. In this example, the volume of the permeate obtained after membrane separation by the nanofiltration membrane accounts for 80% of the total volume of the wine, and the volume of the concentrated wine accounts for 20% of the total volume of the wine. The key physical and chemical properties of the permeate and concentrated wine obtained in this example are shown in Table 1.

[0051] Table 1 Key physical and chemical indicators of wine, permeate and concentrated wine in Example 1

[0052]

[0053]

[0054] As shown in Table 1, during the nanofiltration membrane separation process, the sulfur dioxide and total acid in the permeate used to prepare grape distilled wine have been reduced to a certain extent.

[0055] (2) Use sodium carbonate (Na2CO3) to adjust the pH value of the permeate to 7.

[0056] Calculations and small sample testing indicate that to adjust the pH of the permeate (3.3g / L total acid) to 7, 3.4g of sodium carbonate should be added per liter of permeate. Based on the volume of the permeate to be treated, the total sodium carbonate requirement is calculated. This solution is then prepared with purified water to a 180g / L sodium carbonate solution. This solution is then added online to the permeate, circulated evenly, and allowed to fully react. Finally, the pH is measured to ensure it is ≥6.

[0057] (3) Distillation

[0058] The alkali-treated permeate obtained in step (2) with a pH value adjusted to ≥6 is pumped into a distillation tower for distillation (distillation is carried out using continuous tower distillation, the bottom temperature of the kettle during distillation is 103-105° C., and atmospheric pressure), and the sulfur dioxide content in the obtained grape distilled wine is detected.

[0059] Comparative Example 1:

[0060] This comparative example uses hydrogen peroxide to treat grape wine and then distills it to obtain grape distilled wine, which specifically includes the following steps:

[0061] (1) First, determine the total sulfur dioxide content in the wine.

[0062] (2) Calculate the required amount of hydrogen peroxide (mass fraction 3%) based on the chemical reaction equation of sulfur dioxide and hydrogen peroxide to produce sulfuric acid.

[0063] (3) Based on the calculation result of step (2), add 3% by weight hydrogen peroxide to the wine, wait for full reaction, and measure the sulfur dioxide content. If sulfur dioxide is still present, continue to add 3% by weight hydrogen peroxide in small amounts and multiple times until the sulfur dioxide content drops below 5 mg / L.

[0064] (4) The wine obtained in step (3) from which sulfur dioxide is removed is pumped into a distillation tower for distillation (the distillation adopts continuous tower distillation, the bottom temperature of the kettle during distillation is 103-105° C., and the pressure is normal), and the sulfur dioxide content in the obtained grape distilled wine is detected.

[0065] Comparative Example 2:

[0066] (1) According to step (1) in Example 1, a permeate is obtained.

[0067] (2) Distillation

[0068] The permeate obtained in step (1) is pumped into a distillation tower for distillation (the distillation adopts continuous tower distillation, the bottom temperature of the kettle during distillation is 103-105° C.; normal pressure), and the sulfur dioxide content in the obtained grape distilled wine is detected.

[0069] The sulfur dioxide contents in the grape distilled wines prepared in Example 1, Comparative Example 1, and Comparative Example 2 are shown in Table 2.

[0070] Table 2 Sulfur dioxide content in grape distilled wine prepared in Example 1 and Comparative Examples 1-2

[0071]

[0072] As shown in Table 2, the sulfur dioxide content in the grape distilled wine product prepared in Example 1 is consistent with that in the grape distilled wine product prepared in Comparative Example 1 (1 mg / L and 3 mg / L are basically negligible and are measurement errors).

[0073] The present invention further tasted the grape distilled liquors prepared in Example 1 and Comparative Examples 1-2. The grape distilled liquor product prepared in Example 1 and the grape distilled liquor product prepared in Comparative Example 1 had good typical aroma and taste. The grape distilled liquor product obtained in Comparative Example 2 had a pungent smell and obvious aroma defects.

[0074] From the above examples, it can be seen that the present invention adopts a method of combining nanofiltration membrane separation with alkaline treatment, which can effectively convert sulfur dioxide in wine (raw wine) into bound salts, which are non-volatile and thus no longer carried into the grape distilled wine with ethanol, etc., does not cause equipment corrosion and the production of unpleasant flavors, thereby improving the quality of the grape distilled wine; at the same time, after the wine is separated and filtered by the nanofiltration membrane, the concentrated product (concentrated wine) that does not pass through the membrane has a darker color, higher acidity and tannin content, and has further improved aging potential, and can be used for the blending of normal wine products and other purposes.

[0075] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A wine processing method, characterized in that: The following steps are involved: The wine is subjected to membrane separation using a nanofiltration membrane to obtain a permeate and concentrated wine, wherein the wine contains sulfur dioxide; The permeate is mixed with an alkaline substance permitted for use in GB2760 to obtain an alkali-treated permeate.

2. The processing method according to claim 1, characterized in that The pore size of the nanofiltration membrane is 0.5-2 nm.

3. The treatment method according to claim 1 or 2, wherein the nanofiltration membrane is a polyamide composite nanofiltration membrane; and the membrane structure of the nanofiltration membrane is a roll membrane.

4. The processing method according to claim 1, characterized in that The temperature of the membrane separation is 5-25°C.

5. The processing method according to claim 1 or 4, characterized in that: During the membrane separation, the surface flow rate of the nanofiltration membrane is 0.1 to 2 m / s; During the membrane separation, the transmembrane pressure difference of the nanofiltration membrane is 0 to 2.5 MPa and is not zero.

6. The processing method according to claim 1, characterized in that The wine has a free SO2 content of 18-20 mg / L, a total SO2 content of 105-110 mg / L, a total acid content of 4-5 g / L, and a pH value of 3-4.

7. The processing method according to claim 1 or 6, characterized in that: The permeate has the following contents: free SO2 content of 12-15 mg / L, total SO2 content of 50-54 mg / L, total acid content of 3-3.3 g / L, and pH value of 3-4.

8. The processing method according to claim 1 or 6, characterized in that: The concentrated wine has a free SO2 content of 20-23 mg / L, a total SO2 content of 150-160 mg / L, a total acid content of 5.5-6 g / L, and a pH value of 3-4.

9. The processing method according to claim 1, characterized in that: The alkaline substance includes one or more of sodium carbonate, sodium hydroxide and sodium bicarbonate; The pH value of the alkali-treated permeate is ≥6.

10. A method for preparing grape distilled wine, characterized in that: The following steps are involved: Alkali-treated permeate obtained by the treatment method according to any one of claims 1 to 9; The alkali-treated permeate is used as a raw material for preparing the grape distilled wine.

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