CN113999745A

CN113999745A - Method for reducing content of methanol in passion fruit shell fermented fruit wine

Info

Publication number: CN113999745A
Application number: CN202111503569.6A
Authority: CN
Inventors: 张会香; 程鑫; 赖冰; 贾长龙; 李子院; 崔萌佳; 杨世军; 罗柳吉; 徐思剑
Original assignee: Guilin Wanhe Agricultural Products Co ltd; Guilin University of Technology
Current assignee: Guilin Wanhe Agricultural Products Co ltd; Guilin University of Technology
Priority date: 2021-12-10
Filing date: 2021-12-10
Publication date: 2022-02-01

Abstract

The invention discloses a method for reducing the content of methanol in passion fruit shell fermented fruit wine, which belongs to the technical field of fermented wine and comprises the following steps: adding water into passion fruit shells, pulping, adding pectinase for enzymolysis, heating the enzymolysis liquid after the enzymolysis is finished, adding a pectinase inhibitor, then adding yeast, sugar and sodium metabisulfite for fermentation, and filtering after the fermentation is finished; according to the method, the passion fruit shells are used as raw materials to prepare the fruit wine through fermentation, and the decomposition of pectinase is inhibited by adding a pectinase inhibitor into passion fruit shell pectinase enzymolysis liquid, so that the content of methanol in the prepared passion fruit shell fermented fruit wine is obviously reduced; the passion fruit shell fermented fruit wine is prepared by taking the passion fruit shells as the raw materials, the passion fruit shells are changed into valuable, the method is simple, complicated procedures and equipment such as distillation are not needed, the obtained passion fruit shell fermented fruit wine is low in methanol content and moderate in ethanol content, has a typical passion fruit flavor, is good in taste, and is suitable for popularization and application.

Description

Method for reducing content of methanol in passion fruit shell fermented fruit wine

Technical Field

The invention belongs to the technical field of fermented wine, and particularly relates to a method for reducing the content of methanol in passion fruit shell fermented fruit wine.

Background

The passion fruit is native to the amazon river tropical rainforest region, the passion fruit is mostly produced in the tropical zone, and then the passion fruit is planted in various regions of south America and the like. The passion fruit is rich in various vitamins and dietary fibers, can improve the immunity of a human body, and also has good effects of reducing blood fat, reducing blood pressure and the like. Most of the passion fruit peels are discarded after the pulp is used, which is a waste of resources because the passion fruit shells contain more flavone, alkaloid substances and the like and have higher nutritive value. Therefore, the passion fruit peel can be used for brewing wine. However, the passion fruit peel contains abundant pectin, the juice yield and the yield of fermented wine are low, and pectinase needs to be added during wine brewing to improve the wine yield. However, pectin can generate a large amount of methanol after decomposition, the methanol has great toxicity to human bodies, and when the methanol acts on the nervous system of the human bodies, the methanol can cause blood circulation disorder of brain tissues, generate diffuse lesions and even cause central respiratory failure and death; the methanol also has obvious toxic effect on optic nerves and retina, when the content is too high, the retina and optic nerve lesion can be caused, and finally optic nerve atrophy is caused; methanol is also oxidized to formic acid; they inhibit certain oxidases, and cause disorders in sugar decomposition and body metabolism, leading to accumulation of lactic acid, and acidosis. Moreover, methanol is not easy to be discharged out of the body, and even a small amount of methanol can cause chronic poisoning of people. Therefore, the methanol content is regulated and controlled in the process of brewing the fruit wine by taking the passion fruit shells as raw materials, the methanol content is reduced, and the method has important significance for improving the quality and safety of the fruit wine. At present, many researches on reduction of methanol content in fruit wine brewed from other raw materials exist, but no literature report on how to reduce the methanol content in passion fruit shell fruit wine exists at present.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a method for reducing the content of methanol in passion fruit shell fermented fruit wine.

In order to achieve the purpose, the invention provides the following technical scheme:

the invention provides a method for reducing the content of methanol in passion fruit shell fermented fruit wine, which comprises the following steps: adding water into passion fruit shells, pulping, adding pectinase for enzymolysis, heating the enzymolysis liquid after the enzymolysis is finished, adding a pectinase inhibitor, then adding yeast, sugar and sodium metabisulfite for fermentation, and filtering after the fermentation is finished.

Preferably, the water adding amount is 1-2 times of the weight of the passion fruit shells.

Preferably, the addition amount of the pectinase is 0.10-0.17% of the weight of the passion fruit shell; the enzymolysis temperature is 45 ℃ and the time is 2 h.

Preferably, the heating temperature is 80-88 ℃ and the time is 10-15 min.

Preferably, the pectinase inhibitor is gallic acid or bentonite, and the addition amount of the pectinase inhibitor in each liter of enzymolysis liquid is 10 mg.

Preferably, the pectinase, the yeast and the sodium metabisulfite are added after being dissolved in water at the temperature of 40-45 ℃, and the using amount of the yeast is 0.02% of the weight of the passion fruit shells.

Preferably, the sodium metabisulfite is added in an amount of 0.005% by weight of the passion fruit shells.

Preferably, the sugar is white granulated sugar, and the adding method comprises the steps of adding 30% of the weight of the passion fruit shells when fermentation is started, fermenting until the sugar degree is stable, adding the white granulated sugar until the sugar degree is 15 DEG Bx, filtering after the sugar degree is stabilized again, and adding the white granulated sugar into the filtrate again until the sugar degree is 15 DEG Bx.

Preferably, the fermentation is performed under closed conditions, and the fermentation is terminated after the sugar degree in the filtrate is stabilized.

The invention also provides the low-methanol passion fruit shell fermented fruit wine prepared by the method.

Compared with the prior art, the invention has the following beneficial effects:

in the process of preparing the fruit wine by fermenting the passion fruit shells serving as the raw materials, the decomposition of pectinase is inhibited by adding the pectinase inhibitor into the passion fruit shell pectinase enzymolysis liquid, so that the methanol content in the prepared passion fruit shell fermented fruit wine is obviously reduced.

The method is simple, complex procedures and equipment such as distillation and the like are not needed, the methanol content of the prepared passion fruit shell fermented fruit wine can be reduced to below 400mg/L, the ethanol content is moderate, the typical passion fruit flavor is realized, the taste is good, and the method is suitable for popularization and application.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a result graph of the effect of heat treatment temperature on the content of methanol and ethanol in passion fruit shell fermented fruit wine;

FIG. 2 is a result graph of the effect of heat treatment time on the methanol and ethanol content in passion fruit shell fermented fruit wine;

FIG. 3 is a result graph of the effect of pectinase dosage on the methanol and ethanol content in passion fruit shell fermented fruit wine;

FIG. 4 is a result chart of the effect of different pectinase inhibitors on the methanol and ethanol content in passion fruit shell fermented fruit wine.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, 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 invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The description and examples are intended to be illustrative only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

The passion fruit shells adopted in the following embodiments are provided by Guilin Wanhe agricultural products Co., Ltd, the adopted yeast is Angel RW active fruit wine dry yeast of Angel Yeast Co., Ltd, the adopted pectinase is purchased from Shandong Kete enzyme preparation Co., Ltd, the enzyme activity is 3 ten thousand U/g, and the raw materials are all food grade; other reagents used in the following examples were all domestic analytical purifiers.

The description will not be repeated below.

Example 1

The preparation method of the passion fruit shell fermented fruit wine comprises the following steps:

dissolving pectinase in water at 45 ℃ according to the mass-to-volume ratio of 1 g: 50mL, adding 1.5 times of water by weight into passion fruit shells, pulping by using a wall breaking machine, dividing into two parts, adding the dissolved pectinase into one part, performing enzymolysis for 2 hours at 45 ℃, and thus obtaining an enzymatic hydrolysate; the other part is not added with pectinase; dissolving sodium pyrosulfite and yeast in water at 45 ℃ according to the mass-to-volume ratio of 1g to 50mL respectively, adding the sodium pyrosulfite and the yeast into the two serosity, wherein the adding amount of the sodium pyrosulfite is 0.005% of the weight of the passion fruit shells, the adding amount of the yeast is 0.02% of the weight of the passion fruit shells, then adding white granulated sugar 30% of the weight of the passion fruit shells into each serosity, uniformly stirring, sealing and fermenting at normal temperature, adding the white granulated sugar into each enzymatic hydrolysate until the sugar degree is 15 degrees Bx after the sugar degree is stable, continuing fermenting until the sugar degree is stable again, filtering by using 4 layers of gauze, adding the white granulated sugar into the filtrate until the sugar degree is 15 degrees Bx, continuing sealing and fermenting until the sugar degree is stable, and filtering to obtain the passion fruit shell fermented fruit wine.

Detecting the contents of methanol and ethanol and the sugar degree in the prepared passion fruit shell fermented fruit wine, wherein the detection method of the contents of the methanol and the ethanol refers to gas chromatography in GB/T15038-2006 general analytical method for wine and fruit wine; the test results of the contents of methanol and ethanol in the fruit wines are shown in the table 1.

Example 2

(1) dissolving pectinase in water at 45 ℃ according to the mass-to-volume ratio of 1 g: 50mL, adding 1.5 times of water by weight into passion fruit shells, pulping by using a wall breaking machine, adding the dissolved pectinase, wherein the addition amount of the pectinase is 0.15% of the weight of the passion fruit shells, and performing enzymolysis for 2 hours at 45 ℃ to obtain an enzymatic hydrolysate;

(2) dividing the enzymolysis liquid obtained in the step (1) into two parts, carrying out heat treatment on one part, carrying out heat treatment in a constant-temperature water bath, setting the temperature of the water bath to be 80 ℃, heating the water bath for 15min, immediately taking out the solution, and cooling the solution to 40 ℃; the other part is not subjected to heat treatment; dissolving sodium pyrosulfite and yeast in water at 45 ℃ according to the mass-to-volume ratio of 1g to 50mL respectively, adding the sodium pyrosulfite into the two groups of enzymatic hydrolysate, wherein the adding amount of the sodium pyrosulfite is 0.005% of the weight of the passion fruit shells, and the adding amount of the yeast is 0.02% of the weight of the passion fruit shells, then adding white granulated sugar 30% of the weight of the passion fruit shells into each group of enzymatic hydrolysate, uniformly stirring, sealing and fermenting at normal temperature, adding the white granulated sugar into each group of enzymatic hydrolysate until the sugar degree is 15 degrees Bx after the sugar degree is stable, continuing to ferment until the sugar degree is stable again, filtering with 4 layers of gauze, adding the white granulated sugar into the filtrate until the sugar degree is 15 degrees Bx again, continuing to ferment in a sealing manner until the sugar degree is stable, and then filtering to obtain the passion fruit shell fermented fruit wine.

The contents of methanol and ethanol in the prepared passion fruit shell fermented fruit wine are detected, and the results are shown in table 1.

TABLE 1

As shown in table 1: the contents of methanol and ethanol in the non-heating group and the heating group are compared to obtain: the content of methanol and ethanol in the heated wine changes obviously, and the temperature is determined to have influence on the content. The experimental data comparing the enzyme-free group and the enzyme-added group show that the methanol content of the enzyme-free group is very low, but the ethanol content is very low, so that the influence of the enzyme on the methanol and the ethanol in the fruit wine is determined.

A single-factor test determines the influence of the type of the pectinase inhibitor, the heat treatment temperature, the heat treatment time and the adding amount of the pectinase on the methanol content, the ethanol content and the sugar degree in the passion fruit shell fermented fruit wine.

Example 3

Influence of heat treatment temperature on methanol and ethanol content in the passion fruit shell fermented fruit wine:

(2) carrying out heat treatment on the enzymolysis liquid obtained in the step (1), wherein the heat treatment is carried out in a constant-temperature water bath, the water bath temperature is set to be four levels of 75 ℃, 80 ℃, 85 ℃ and 90 ℃, and the enzymolysis liquid is immediately taken out and cooled to 40 ℃ after being heated in the water bath for 15 min; dissolving sodium pyrosulfite and yeast in water at 45 ℃ according to the mass-to-volume ratio of 1g to 50mL respectively, adding the sodium pyrosulfite into three groups of enzymatic hydrolysates, wherein the adding amount of the sodium pyrosulfite is 0.005% of the weight of the passion fruit shells, the adding amount of the yeast is 0.02% of the weight of the passion fruit shells, then adding white granulated sugar 30% of the weight of the passion fruit shells into each group of enzymatic hydrolysates, uniformly stirring, sealing and fermenting at normal temperature, adding the white granulated sugar into each group of enzymatic hydrolysates until the sugar degree is 15 degrees Bx after the sugar degree is stable, continuing to ferment until the sugar degree is stable again, filtering with 4 layers of gauze, adding the white granulated sugar into the filtrate until the sugar degree is 15 degrees Bx, continuing to ferment in a sealing manner until the sugar degree is stable, and then filtering to obtain the passion fruit shell fermented fruit wine.

The content of methanol and ethanol in the prepared passion fruit shell fermented fruit wine is detected, and the detection method of the content of the methanol and the ethanol refers to gas chromatography in GB/T15038-2006 general analysis method for wine and fruit wine. The test results of the contents of methanol and ethanol in the fruit wines are shown in figure 1.

As can be seen from FIG. 1, the methanol content decreased with increasing temperature, reaching a minimum at 85 ℃ and was 269.04 mg/L. The temperature rises from 85 to 90 ℃, and considering that the temperature is possibly too high, the pectin is decomposed too fast by itself, and higher methanol is generated. The ethanol content gradually decreased with increasing temperature, reaching a minimum of 85 ℃, and began to increase as the temperature continued to increase. Therefore, 85 ℃ was determined as the optimum heat treatment temperature.

Example 4

Influence of heat treatment time on methanol and ethanol content in the passion fruit shell fermented fruit wine:

the preparation method of the passion fruit shell fermented fruit wine is the same as that in example 3, except that the water bath heating temperature in the step (2) is set to be 85 ℃, the water bath heating time is set to be four levels of 5min, 10min, 15min and 20min, and other operations are the same as those in example 3.

The content of methanol and ethanol in the prepared passion fruit shell fermented fruit wine is detected, and the result is shown in fig. 2.

As shown in fig. 2: the content of methanol is continuously reduced along with the increase of time, and the methanol reaches 401.74mg/L at the minimum at 20 min. The ethanol content is gently reduced within 5-15 min, the reduction range is increased within 15-20 min, and the ethanol content is lowest within 20 min. Although the content of methanol is lowest when the wine is heated for 20min, the content of ethanol is too low, so the wine does not meet the brewing standard. Therefore, the heat treatment time is 15min as the optimum treatment time.

Example 5

Influence of the addition of pectinase on the content of methanol and ethanol in the passion fruit shell fermented fruit wine:

the preparation method of the passion fruit shell fermented fruit wine is the same as that in example 4, except that the addition amount of the pectinase in the step (1) is set to four levels of 0.05%, 0.10%, 0.15% and 0.20% of the weight of the passion fruit shells, the water bath heating time in the step (2) is set to 15min, and other operations are the same as those in example 4.

The content of methanol and ethanol in the prepared passion fruit shell fermented fruit wine is detected, and the result is shown in fig. 3.

As shown in fig. 3: with the increase of the addition amount of the pectinase, the content of the methanol and the ethanol is increased continuously. When the addition amount of the pectinase is 0.10 percent and 0.15 percent, the methanol content is similar, and is 426.01mg/L and 468.38 mg/L; when the addition amount is 0.20%, the methanol content is the maximum, and reaches 751.60 mg/L. The ethanol content has basically the same change trend, but the difference between the addition amount of the pectinase of 0.10 percent and the addition amount of the pectinase of 0.15 percent is larger, namely 5.09mL/100mL and 10.40mL/100 mL. Therefore, the optimum amount of pectinase to be added is 0.15% by taking the contents of ethanol and methanol into consideration.

Example 6

Influence of pectinase inhibitor species on methanol and ethanol content in passion fruit shell fermented fruit wine:

(2) heating the enzymatic hydrolysate obtained in the step (1) in a water bath at 85 ℃ for 15min, immediately taking out and cooling the enzymatic hydrolysate, dividing the enzymatic hydrolysate into three groups A-C, respectively adding pectinase inhibitors of gallic acid and bentonite into the enzymatic hydrolysates of the group A and the group B when the temperature is reduced to 40 ℃, so that the contents of the gallic acid and the bentonite in the enzymatic hydrolysate are both 10mg/L, and taking the group C as a blank control group without adding any pectinase inhibitor; dissolving sodium pyrosulfite and yeast in water at 45 ℃ according to the mass-to-volume ratio of 1g to 50mL respectively, adding the sodium pyrosulfite into three groups of enzymatic hydrolysates, wherein the adding amount of the sodium pyrosulfite is 0.005% of the weight of the passion fruit shells, the adding amount of the yeast is 0.02% of the weight of the passion fruit shells, then adding white granulated sugar 30% of the weight of the passion fruit shells into each group of enzymatic hydrolysates, uniformly stirring, sealing and fermenting at normal temperature, adding the white granulated sugar into each group of enzymatic hydrolysates until the sugar degree is 15 degrees Bx after the sugar degree is stable, continuing to ferment until the sugar degree is stable again, filtering with 4 layers of gauze, adding the white granulated sugar into the filtrate until the sugar degree is 15 degrees Bx, continuing to ferment in a sealing manner until the sugar degree is stable, and then filtering to obtain the passion fruit shell fermented fruit wine.

The content of methanol and ethanol in the prepared passion fruit shell fermented fruit wine is detected, and the result is shown in fig. 4.

As shown in FIG. 4, the enzyme inhibitors were able to reduce the methanol content compared to the blank control, wherein the methanol content was reduced more in the 10mg/L gallic acid group and less in the 10mg/L bentonite group, but the ethanol content was also changed in the same manner. Because the change range of the ethanol content is not large, 10mg/L of gallic acid is selected as the optimal pectinase inhibitor according to the comparison of the results of the methanol.

Example 7

Orthogonal test optimized preparation process of passion fruit shell fermented fruit wine

On the basis of the single-factor experiment result, the heat treatment temperature (A), the heat treatment time (B) and the addition amount (C) of the pectinase are selected as factors, and the pectinase inhibitor gallic acid is added in each group of experiments, so that the content of the gallic acid in the enzymatic hydrolysate is 10 mg/L. Taking the contents of methanol and ethanol in the fermented fruit wine as indexes, selecting L₉(3⁴) And (4) designing an orthogonal test and determining the optimal process condition by using an orthogonal table. The factor levels are shown in table 2.

TABLE 2

The experimental results are shown in Table 3 and the results of the ANOVA are shown in Table 4.

TABLE 3

TABLE 4

From table 3, the primary and secondary order affecting methanol content is: pectinase addition amount > temperature > time. The optimal conditions are that the heat treatment temperature is 87 ℃, the heat treatment time is 17min, and the addition amount of the pectinase is 0.17%. The methanol content under these conditions was 88.99 mg/L.

The primary and secondary sequence affecting ethanol content is: the temperature and the time are larger than the addition amount of the pectinase, and the temperature, the time and the pectinase have small influence on the content of the ethanol in the fruit wine. The optimal process conditions of the ethanol comprise that the heat treatment temperature is 85 ℃, the heat treatment time is 13min, and the addition amount of the pectinase is 0.13%.

The fruit wine obtained by the optimal process factor determined by taking methanol as an index has too low ethanol content to meet the production requirement, so the No. 8 experiment in the orthogonal experiment is finally determined as the optimal process by integrating the experimental results of the methanol and the ethanol. Namely, the heat treatment temperature is 87 ℃, the heat treatment time is 15min, and the addition amount of the pectinase is 0.13%.

As can be seen from table 4, the heat treatment temperature and the pectinase addition amount significantly affected the methanol content, while the time did not significantly affect the methanol content.

Example 8

(1) dissolving pectinase in water at 45 ℃ according to the mass-to-volume ratio of 1 g: 50mL, cutting passion fruit shells into small pieces of (4 +/-1) cm multiplied by (4 +/-1) cm, adding 1.5 times of water by weight, adding the dissolved pectinase, wherein the adding amount of the pectinase is 0.13 percent of the weight of the passion fruit shells, and performing enzymolysis for 2 hours at 45 ℃ to obtain an enzymatic hydrolysate;

(2) heating the enzymolysis liquid obtained in the step (1) in a water bath at 87 ℃ for 15min, immediately taking out, cooling to 40 ℃, and adding a pectinase inhibitor gallic acid to ensure that the content of the gallic acid in the enzymolysis liquid is 10 mg/L; dissolving sodium pyrosulfite and yeast in water at 45 ℃ according to the mass-to-volume ratio of 1g to 50mL respectively, adding the sodium pyrosulfite into an enzymolysis solution, wherein the adding amount of the sodium pyrosulfite is 0.005% of the weight of the passion fruit shells, and the adding amount of the yeast is 0.02% of the weight of the passion fruit shells, then adding white granulated sugar 30% of the weight of the passion fruit shells into the enzymolysis solution, uniformly stirring, sealing and fermenting at normal temperature, adding the white granulated sugar into a fermentation liquid until the sugar degree is 15 degrees Bx after the sugar degree is stable, continuing to ferment until the sugar degree is stable again, filtering by using 4 layers of gauze, adding the white granulated sugar into the obtained filtrate again until the sugar degree is 15 degrees Bx, continuing to seal and ferment until the sugar degree is stable, and then filtering to obtain the passion fruit shell fermented fruit wine.

Example 9

(2) heating the enzymolysis liquid obtained in the step (1) in a water bath at 87 ℃ for 15min, immediately taking out the enzymolysis liquid, cooling to room temperature, and adding sodium erythorbate to enable the mass percentage of the sodium erythorbate in the enzymolysis liquid to be 0.015%; dissolving sodium pyrosulfite and yeast in water at 45 ℃ according to the mass-to-volume ratio of 1g to 50mL respectively, adding the sodium pyrosulfite into an enzymolysis solution, wherein the adding amount of the sodium pyrosulfite is 0.005% of the weight of the passion fruit shells, and the adding amount of the yeast is 0.02% of the weight of the passion fruit shells, then adding white granulated sugar 30% of the weight of the passion fruit shells into the enzymolysis solution, uniformly stirring, sealing and fermenting at normal temperature, adding the white granulated sugar into a fermentation liquid until the sugar degree is 15 degrees Bx after the sugar degree is stable, continuing to ferment until the sugar degree is stable again, filtering by using 4 layers of gauze, adding the white granulated sugar into the obtained filtrate again until the sugar degree is 15 degrees Bx, continuing to seal and ferment until the sugar degree is stable, and then filtering to obtain the passion fruit shell fermented fruit wine.

The contents of methanol and ethanol in the passion fruit shell fermented fruit wine prepared in example 8 and example 9 were measured, and the results are shown in table 5.

TABLE 5

Group of	Methanol content (mg/mL)	Ethanol content (mg/100mL)
			Example 8	141.23	8.10
Example 9	145.18	9.32

As can be seen from Table 6, the cut passion fruit shells can reduce the content of methanol in the fruit wine, and the content of ethanol is slightly reduced, but the quality of the product is not affected; after sodium erythorbate is added into fermentation liquor, fruit wine with lower methanol content can be obtained under the condition of not adding pectinase inhibitor, which shows that sodium erythorbate also has a certain inhibiting effect on the generation of methanol.

The above description is only for the preferred embodiment of the present invention, and the protection scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical scope of the present invention, the technical solution and the inventive concept of the present invention equivalent or change within the technical scope of the present invention.

Claims

1. A method for reducing the content of methanol in passion fruit shell fermented fruit wine is characterized by comprising the following steps: adding water into passion fruit shells, pulping, adding pectinase for enzymolysis, heating the enzymolysis liquid after the enzymolysis is finished, adding a pectinase inhibitor, then adding yeast, sugar and sodium metabisulfite for fermentation, and filtering after the fermentation is finished.

2. The method according to claim 1, wherein the amount of water added is 1 to 2 times the weight of the passion fruit shells.

3. The method according to claim 1, wherein the pectinase is added in an amount of 0.10-0.17% of the weight of the passion fruit shell; the enzymolysis temperature is 45 ℃ and the time is 2 h.

4. The method according to claim 1, wherein the heating temperature is 80 to 88 ℃ and the time is 10 to 15 min.

5. The method according to claim 1, wherein the pectinase inhibitor is gallic acid or bentonite, and the amount of the pectinase inhibitor added is 10mg per liter of the enzymatic hydrolysate.

6. The method according to claim 1, wherein the pectinase, yeast and sodium metabisulfite are added after being dissolved in water at 40-45 ℃, and the amount of the yeast is 0.02% of the weight of the passion fruit shells.

7. The method according to claim 1, wherein the sodium metabisulphite is added in an amount of 0.005% by weight of the passion fruit shells.

8. The method according to claim 1, wherein the sugar is white granulated sugar, and the adding method comprises adding 30% of the weight of the passion fruit shells at the beginning of fermentation, fermenting until the sugar degree is stable, adding the white granulated sugar until the sugar degree is 15 ° Bx, filtering after the sugar degree is stabilized again, and adding the white granulated sugar into the filtrate again until the sugar degree is 15 ° Bx.

9. The method of claim 8, wherein the fermentation is performed under closed conditions and the fermentation is terminated after the sugar content of the filtrate has stabilized.

10. A low-methanol passion fruit shell fermented fruit wine prepared by the method according to any one of claims 1-9.