CN110564559B

CN110564559B - Fermented noni fruit wine and preparation method thereof

Info

Publication number: CN110564559B
Application number: CN201910876023.1A
Authority: CN
Inventors: 孟君; 曾新安; 李晓娟; 蔡锦林
Original assignee: Qianjin Pharmaceutical Co ltd; South China University of Technology SCUT
Current assignee: Qianjin Pharmaceutical Co ltd; South China University of Technology SCUT
Priority date: 2019-09-17
Filing date: 2019-09-17
Publication date: 2022-12-30
Anticipated expiration: 2039-09-17
Also published as: CN110564559A

Abstract

The invention belongs to the technical field of food fermentation, and relates to fermented noni fruit wine and a preparation method thereof. The preparation method of the fermented noni fruit wine comprises the steps of obtaining clear noni fruit juice, adjusting sugar content and pH, inoculating yeast for fermentation, post-fermentation, blending, sterilization and the like. The invention limits the best fermentation condition, combines the combined deacidification of calcium carbonate and potassium bicarbonate and other steps, and the prepared fruit wine has no alkaline taste and good flavor and taste; the content of methanol and fusel oil can be obviously reduced, and the body can not be uncomfortable; and no stabilizer SO with potential safety hazard is used ₂ On the premise, the fruit wine can also keep stronger stability and has high safety.

Description

Fermented noni fruit wine and preparation method thereof

Technical Field

The invention belongs to the technical field of food fermentation. More particularly, relates to fermented noni fruit wine and a preparation method thereof.

Background

Noni, also known as morinda citrifolia, is known as "vomiting nut" because it emits a unique odor of butyric acid when it is ripe, with its irritating and emetic properties. In scientific research, the morinda citrifolia contains various chemical components which are beneficial to human bodies, such as scopoletin, potassium, vitamin C, terpenoids, alkaloids, anthraquinone, methyl ether, sitosterol, carotene, vitamin A, flavone, linoleic acid, alizarin, amino acid and the like, and has health-care effects of resisting oxidation, cancers, diminishing inflammation and the like. Therefore, noni has high edible and medicinal values, and those skilled in the art are also actively researching and developing the application of noni in the aspects of eating, health care and the like.

For example, the Chinese patent application CN104630005A discloses a noni fruit health wine raw material, a noni fruit health wine and a preparation method thereof, the noni fruit health wine is mainly prepared from white spirit with the alcoholic strength of more than or equal to 50 degrees, noni fruit powder, medlar, jujube and crystal sugar, the percolate obtained by percolating the noni fruit powder with the white spirit is mixed with the ultrasonic extraction concentrated solution of the medlar and the jujube, and other auxiliary materials are added for preparation, so that the noni fruit health wine is prepared, the preparation method is simple, the taste is good, and the noni fruit health wine has a good health care function. However, simple percolation of morinda citrifolia with white spirit is difficult to remove the special emetic smell of morinda citrifolia, and only the extracted effective components can be utilized, so that the effective components of morinda citrifolia cannot be completely utilized, and the waste of resources is easily caused.

Further, in the research, the technical personnel in the field find that the noni fruit wine prepared by adopting the fermentation method can remove the special emetic smell of noni by fermentation on one hand; on the other hand, the nutrient and health-care components of noni can be better utilized by a microbial fermentation method. For example, chinese patent application CN105505680A discloses a noni compound fruit wine and a preparation method thereof, which solves the technical problem that a fermentation process cannot be started by antibacterial substances contained in noni by limiting the pH of a key factor to be not less than 6, and adopts the measures on sugar degree, fermentation temperature and SO ₂ Further limiting the conditions of bacteriostasis, yeast type and the like, and fermenting for 5-12 days to obtain the product with beautiful color, clarity and transparency; strong fruit flavor and no peculiar smell; the noni composite fruit wine has a full wine body, is mellow and harmonious and has a lingering aftertaste. However, the applicant finds in practice that the pH of the noni fruit juice is about 3-4, the pH is adjusted to be not less than 6, and a large amount of alkaline reagent potassium bicarbonate needs to be added, so that the prepared noni fruit wine has obvious alkaline taste, and the edible mouthfeel is greatly influenced; in addition, SO for bacteriostasis, antioxidation and stability improvement is added ₂ Has certain chronic effect on human bodyToxicity, adverse reactions such as allergy, stomach tissue lesion and the like may occur; in addition, the preparation steps are complicated, the required time is long, and the method is not suitable for large-scale industrial production.

Therefore, it is urgently needed to provide a fermented noni fruit wine and a preparation method thereof, which have high safety, good flavor and mouthfeel and a simple preparation method.

Disclosure of Invention

The invention aims to solve the technical problem of overcoming the alkaline taste and antioxidant SO existing in the existing fermented noni fruit wine added with a large amount of alkaline reagents ₂ Has the defects of chronic toxicity to human bodies, complex preparation method and long time consumption, and provides the fermented noni fruit wine with high safety, strong stability, good flavor and taste and simple preparation method and the preparation method thereof.

The above purpose of the invention is realized by the following technical scheme:

a preparation method of fermented noni wine comprises the following steps:

s1, preparing noni fruit into clear juice;

s2, adjusting the sugar content of the clear juice obtained in the step S1 to be 100-220g/L, and adjusting the pH value of the clear juice to be more than 5.5 by using calcium carbonate and potassium bicarbonate through two-step deacidification;

s3, pasteurizing the clear juice adjusted in the step S2 at 60-80 ℃ for 20-30min, cooling to 35-40 ℃, inoculating activated yeast, and fermenting at 24-28 ℃ for 5-10 days;

and S4, after fermentation is finished, performing after-fermentation, filtering, blending, carbon dioxide synergistic ultrahigh pressure sterilization and filling to obtain the product.

Further, the step S1 of preparing the noni fruit into the clear juice includes the following steps: selecting Morinda citrifolia with moderate hardness, mechanically crushing after 3-5 days of after-ripening, mixing the crushed fruit paste with fruit juice, and squeezing with water bag to obtain clear fruit juice.

Furthermore, the two-step deacidification method by using calcium carbonate and potassium bicarbonate in the step S2 comprises the following steps: adding 5-15g/L calcium carbonate into clear juice, mixing, naturally settling for 1-2 days, adding 2-8g/L potassium bicarbonate into the supernatant, mixing and dissolving, detecting pH to be more than 5.5, and standing overnight.

Further, the sugar content of the clear juice in the step S2 is 100-200g/L, and the pH =6.0-7.5.

Preferably, the sugar content of the juice clear juice in the step S2 is 200g/L, and the pH =7.0.

Furthermore, 0.5-3g/L ammonium sulfate is also required to be added in the step S2.

Preferably, 1-3g/L ammonium sulfate is also added in the step S2.

More preferably, 1g/L ammonium sulfate is also added in the step S2.

Further, the inoculation amount of the yeast in the step S3 is 350-500mg/L.

Preferably, the inoculation amount of the yeast in the step S3 is 400-450mg/L.

More preferably, the inoculation amount of the yeast in the step S3 is 450mg/L.

Still further, the yeast in step S3 is selected from one or two of LV yeast and Angel high activity dry yeast.

Further, the carbon dioxide cooperating with the ultra-high pressure sterilization method in step S4 comprises: the volume ratio of carbon dioxide and fruit wine is 0.80-1.50, the pressure is 100-1000MPa, the temperature is 10-35 deg.C, and sterilization is carried out for 1-60min.

In addition, the invention also provides the fermented noni fruit wine prepared by the preparation method.

Further, the alcoholic strength of the fermented noni fruit wine is 6-13 degrees.

In addition, the invention also provides the fermented noni compound fruit wine prepared by the preparation method, the clear noni fruit juice obtained in the step S1 is firstly mixed with other fruit juice to obtain mixed clear fruit juice, and then the subsequent operation is carried out.

Preferably, the other fruit juice can be one or more of amur grape juice, sanhua plum juice or peach juice.

Further, the mixing volume ratio of the noni juice to other juice is 1 (1-4).

Preferably, the mixing volume ratio of the noni juice to other juice is 1 (1-3).

More preferably, the mixing volume ratio of the noni juice and other juice is 1.

According to the invention, through a large amount of research and exploration, the influence of the pH value, the fermentation temperature, the sugar content of the clear juice of the fruit juice and the yeast inoculation amount on the alcoholic strength of the fruit wine is investigated, and the optimal fermentation condition is determined by considering all factors. However, when the pH value is adjusted, a large amount of alkaline reagent is required to be added, and when only one alkaline reagent is used, such as calcium carbonate or potassium tartrate, calcium ions in the fruit wine are greatly increased, so that the stability of the fruit wine is influenced, and the fermentation of yeast can be inhibited when the residual quantity is too high; if a large amount of potassium bicarbonate is added, certain influence is generated on the aroma and the taste of the fruit wine, so that the aroma is weak, and the fruit wine contains alkaline taste during tasting. The applicant surprisingly discovers in practice that the clear juice is firstly subjected to deacidification treatment by using calcium carbonate, is precipitated for 1-2 days, and then is siphoned to obtain supernatant, potassium bicarbonate is added for further deacidification, and the supernatant is placed overnight and then is subjected to subsequent steps of inoculation, fermentation and the like, so that the prepared noni fruit wine is high in safety, strong in stability, and good in flavor and taste.

Experimental example 2 can prove that the fruit wine prepared by the acidity adjusting mode of adding the alkaline reagent in groups 1-4 at one time has alkaline tastes of different degrees, low sensory score, higher methanol and fusel oil content and low safety; the fruit wine in 3-6 months has precipitation, obvious color change and taste change and poor stability. Different alkaline reagents are added step by step in groups 6-8, but the unique aroma of noni is light, the taste and flavor are poor, the fruit wine in 9 months has precipitation and obvious discoloration and taste change, and the stability is not high. In the fruit wine prepared in group 5 according to the embodiment 1, the content of methanol and fusel oil is low, uncomfortable symptoms can not be caused to a human body, and the fruit wine has good flavor and taste and good stability. The applicant believes that it is possible to remove part of the pectins by precipitation overnight when stepwise deacidification is carried out using calcium carbonate and potassium bicarbonate, thereby reducing the methanol and fusel oil produced by pectin decomposition during fermentation.

The invention has the following beneficial effects:

(1) The invention combines calcium carbonate and carbonic acid by defining the optimal fermentation conditionsThe combined deacidification of the hydrogen and the potassium and other steps are adopted, so that the prepared fruit wine has no alkaline taste and good flavor and mouthfeel; the methanol and fusel oil content is low, and the original flavor of noni is kept, and simultaneously, the body can not be uncomfortable; and no stabilizer SO with potential safety hazard is used ₂ On the premise, the fruit wine can also keep stronger stability and has high safety.

(2) According to the other fermented noni compound fruit wine provided by the invention, other fruit juice and noni fruit juice are added for fermentation, so that the flavor of the fruit wine can be enriched, the mouthfeel and the nutritional value can be improved, the favorite requirements of different consumers can be met, and the flavor and the mouthfeel are good.

Drawings

FIG. 1 shows the effect of pH on the alcoholic strength of fermented noni wine.

FIG. 2 is the effect of fermentation temperature on the alcoholic strength of fermented noni wine.

FIG. 3 shows the effect of sugar content in clear juice on alcoholic strength of fermented noni wine.

FIG. 4 shows the effect of yeast inoculation amount on alcoholic strength of fermented noni wine.

Detailed Description

The present invention is further illustrated by the following specific examples, which are not intended to limit the invention in any way. Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.

Unless otherwise indicated, reagents and materials used in the following examples are commercially available.

Example 1 fermented noni wine

The preparation method comprises the following steps:

s1, selecting noni fruits with moderate hardness, mechanically crushing the noni fruits after 3 days of after-ripening, uniformly mixing crushed fruit paste with fruit juice, and squeezing the mixture in water bags to obtain clear fruit juice;

s2, adjusting the clear juice obtained in the step S1 by using white granulated sugar and an alkaline reagent, adding the white granulated sugar into the clear juice to ensure that the sugar content of the clear juice is 200g/L, then adding 10g/L calcium carbonate, mixing uniformly, naturally settling for 1 day, siphoning the supernatant, adding 5g/L potassium bicarbonate, mixing and dissolving to ensure that the pH is =7, and standing overnight;

s3, pasteurizing the juice clear juice adjusted in the step S3 at 80 ℃ for 20min, cooling to 40 ℃, inoculating activated Angel high-activity dry yeast with the inoculation amount of 450mg/L, and fermenting at 24 ℃ for 6 days;

s4, after fermentation is finished, performing after-fermentation, filtering, blending, carbon dioxide synergistic ultrahigh pressure sterilization and filling to obtain the product;

wherein the carbon dioxide cooperated ultrahigh pressure sterilization method in the step S4 comprises the following steps: the volume ratio of carbon dioxide and fruit wine is 1.0, the pressure is 550MPa, the temperature is 30 ℃, and the sterilization is carried out for 20min.

Example 2 fermented noni wine

The preparation method comprises the following steps:

s1, selecting noni fruits with moderate hardness, mechanically crushing the noni fruits after 4 days of after-ripening, uniformly mixing crushed fruit paste with fruit juice, and squeezing the mixture in water bags to obtain clear fruit juice;

s2, adjusting the clear juice obtained in the step S1 by using white granulated sugar and an alkaline reagent, adding the white granulated sugar into the clear juice to ensure that the sugar content of the clear juice is 150g/L, then adding 15g/L calcium carbonate, mixing uniformly, naturally settling for 1.5 days, adding 2g/L potassium bicarbonate into siphoned supernatant, mixing and dissolving to ensure that the pH value is =7.2, and standing overnight;

s3, pasteurizing the clear juice adjusted in the step S3 at 75 ℃ for 25min, cooling to 35 ℃, inoculating activated LV yeast with the inoculation amount of 350mg/L, and fermenting at 25 ℃ for 10 days;

s4, after fermentation, performing after-fermentation, filtering, blending, carbon dioxide-cooperated ultrahigh pressure sterilization, and filling to obtain the product;

the carbon dioxide-cooperated ultrahigh pressure sterilization method in the step S4 comprises the following steps: the volume ratio of carbon dioxide and fruit wine is 1.2, the pressure is 650MPa, the temperature is 25 ℃, and the sterilization is carried out for 25min.

Example 3 fermented noni wine

The preparation method comprises the following steps:

s2, adjusting the juice clear juice obtained in the step S1 by using white granulated sugar and an alkaline reagent, adding the white granulated sugar into the juice clear juice to ensure that the sugar content of the juice clear juice is 220g/L, adding 0.5g/L of ammonium sulfate, then adding 5g/L of calcium carbonate, mixing uniformly, naturally settling for 1 day, adding 8g/L of potassium bicarbonate into siphoned supernatant, mixing and dissolving, then enabling the pH to be =6.8, and standing overnight;

s3, pasteurizing the juice clear juice adjusted in the step S3 at 70 ℃ for 30min, cooling to 38 ℃, inoculating activated Angel high-activity dry yeast with the inoculation amount of 400mg/L, and fermenting at 28 ℃ for 5 days;

the carbon dioxide-cooperated ultrahigh pressure sterilization method in the step S4 comprises the following steps: the volume ratio of carbon dioxide and fruit wine is 0.8, the pressure is 800MPa, the temperature is 25 ℃, and the sterilization is carried out for 10min.

Example 4 fermented noni composite fruit wine

The preparation method comprises the following steps:

s1, selecting noni fruits with moderate hardness, mechanically crushing the noni fruits after 3 days of after-ripening, uniformly mixing crushed fruit paste with fruit juice, and squeezing by water sacs to obtain clear noni fruit juice; selecting ripe amur grape, mechanically crushing, uniformly mixing the crushed fruit paste with fruit juice, squeezing by a water sac to obtain a amur grape clear juice, and mixing the noni fruit clear juice with the amur grape clear juice according to a volume ratio of 1;

s2, adjusting the mixed juice clear juice obtained in the step S1 by using white granulated sugar, ammonium sulfate and an alkaline reagent, adding the white granulated sugar into the mixed juice clear juice to ensure that the sugar content of the juice clear juice is 100g/L, adding 1g/L of ammonium sulfate, adding 10g/L of calcium carbonate, mixing uniformly, naturally settling for 1 day, adding 6g/L of potassium bicarbonate into siphoned supernatant, mixing and dissolving to ensure that the pH value is =7.0, and standing overnight;

s3, pasteurizing the juice clear juice adjusted in the step S3 at 80 ℃ for 20min, cooling to 37 ℃, inoculating activated Angel high-activity dry yeast with the inoculation amount of 500mg/L, and fermenting at 28 ℃ for 5 days;

the carbon dioxide-cooperated ultrahigh pressure sterilization method in the step S4 comprises the following steps: the volume ratio of carbon dioxide and fruit wine is 1.5, the pressure is 550MPa, the temperature is 30 ℃, and the sterilization is carried out for 20min.

Example 5A fermented noni composite fruit wine

The preparation method comprises the following steps:

s1, selecting noni fruits with moderate hardness, mechanically crushing the noni fruits after 4 days of after-ripening, uniformly mixing crushed fruit paste with fruit juice, and squeezing the mixture in a water bag to obtain clear noni fruit juice; selecting mature Sanhua plum, mechanically crushing, uniformly mixing the crushed fruit paste with fruit juice, squeezing by a water bag to obtain clear Sanhua plum juice, and mixing the clear noni fruit juice with the clear Sanhua plum juice according to a volume ratio of 1;

s2, adjusting the mixed juice clear juice obtained in the step S1 by using white granulated sugar, ammonium sulfate and an alkaline reagent, adding the white granulated sugar into the mixed juice clear juice to ensure that the sugar content of the juice clear juice is 150g/L, adding 2g/L of ammonium sulfate, adding 12g/L of calcium carbonate, mixing uniformly, naturally settling for 1.5 days, adding 4g/L of potassium bicarbonate into siphoned supernatant, mixing and dissolving to ensure that the pH value is =7.2, and standing overnight;

s3, pasteurizing the clear juice adjusted in the step S3 at 75 ℃ for 25min, cooling to 35 ℃, inoculating activated LV yeast with the inoculation amount of 400mg/L, and fermenting at 25 ℃ for 7 days;

wherein the carbon dioxide cooperated ultrahigh pressure sterilization method in the step S4 comprises the following steps: the volume ratio of carbon dioxide and fruit wine is 1.2, the pressure is 650MPa, the temperature is 25 ℃, and the sterilization is carried out for 25min.

Example 6 fermented noni composite fruit wine

The preparation method comprises the following steps:

s1, selecting noni fruits with moderate hardness, mechanically crushing the noni fruits after 3 days of after-ripening, uniformly mixing crushed fruit paste with fruit juice, and squeezing by water sacs to obtain clear noni fruit juice; selecting ripe peaches, mechanically crushing, uniformly mixing the crushed fruit paste with the juice, squeezing by water sacs to obtain clear peach juice, and mixing the clear noni fruit juice with the clear peach juice according to a volume ratio of 1;

s2, adjusting the mixed juice obtained in the step S1 by using white granulated sugar, ammonium sulfate and an alkaline reagent, adding the white granulated sugar into the mixed juice to ensure that the sugar content of the juice is 180g/L, adding 3g/L of ammonium sulfate, adding 8g/L of calcium carbonate, mixing uniformly, naturally settling for 1 day, siphoning supernatant, adding 6g/L of potassium bicarbonate, mixing and dissolving to ensure that the pH value is =6.8, and standing overnight;

s3, pasteurizing the juice clear juice adjusted in the step S3 at 70 ℃ for 30min, cooling to 38 ℃, inoculating activated Angel high-activity dry yeast with the inoculation amount of 500mg/L, and fermenting at 26 ℃ for 6 days;

wherein the carbon dioxide cooperated ultrahigh pressure sterilization method in the step S4 comprises the following steps: the volume ratio of carbon dioxide and fruit wine is 0.8, the pressure is 1000MPa, the temperature is 25 ℃, and the sterilization is carried out for 10min.

Experimental example 1 influence of different fermentation conditions on alcohol content of fruit wine

1. Single factor experiment

(1) Influence of pH value on alcoholic strength of fermented noni fruit wine

Reference example 1 a method for preparing fermented noni wine was carried out except that a series of fermented noni wine was prepared using pH as a single factor variable, and the alcoholic strength of the wine at the end of fermentation was measured, and the results are shown in fig. 1.

As can be seen from figure 1, the pH of the clear noni juice is about 3.5, when the pH is adjusted to be less than or equal to 5, the noni juice has obvious growth inhibition effect on yeast due to high noni polyphenol content, the yeast can not carry out normal metabolism, the growth and metabolism are stopped within 48h after yeast inoculation, no bubbles are generated, the total sugar content is kept unchanged, and the yeast cells are observed to be completely dead after being dyed by eosin methylene blue dyeing agent under a microscope; when the pH value of 5 & ltSUP & gt is less than or equal to 7, the acidity is weakened, the total phenol content is reduced, the inhibition effect on yeast is weakened, and the alcoholic strength of the fruit wine is gradually increased; when the pH is >7, the alcohol content tends to be smooth.

(2) Influence of fermentation temperature on alcoholic strength of fermented noni fruit wine

Reference example 1 a method for preparing fermented noni wine, except that a series of fermented noni wine was prepared using fermentation temperature as a single factor variable, and the alcoholic strength of the wine at the end of fermentation was measured, the results are shown in fig. 2.

As can be seen from figure 2, the growth and metabolism of the yeast are gradually accelerated along with the rise of the temperature, the fermentation speed is fastest at 28 ℃, and the alcoholic strength of the obtained fruit wine is highest; however, too high temperature can increase the content of volatile acid and higher alcohol in the product, and affect the quality of the fruit wine.

(3) Influence of sugar content of clear juice on alcoholic strength of fermented noni fruit wine

Reference example 1 a method for preparing fermented noni wine was carried out except that a series of fermented noni wine was prepared using sugar content of clear juice as a single factor variable, and alcoholic strength of the wine at the end of fermentation was measured, and the results are shown in fig. 3.

The noni juice has low sugar content of 45g/L, and needs additional carbon source (such as white sugar or sucrose) to provide energy for yeast metabolism. As can be seen from figure 3, as the sugar content of the clear juice of the fruit juice is increased, the yeast metabolism has sufficient nutrients, and the alcoholic strength of the fruit wine is also gradually increased; however, when the sugar content of the juice exceeds 200g/L, the alcoholic strength of the fruit wine begins to decrease because the osmotic pressure is increased due to the excessively high sugar content of the juice, and the growth and metabolism of yeast are inhibited.

(4) Influence of yeast inoculation amount on alcoholic strength of fermented noni fruit wine

Reference example 1 a method for preparing fermented noni wine was carried out except that a series of fermented noni wine was prepared using the yeast inoculation amount as a single factor variable, and the alcoholic strength of the wine at the end of fermentation was measured, and the results are shown in fig. 4.

Because noni phenolic substances have a strong inhibition effect on yeast growth metabolism, proper yeast needs to be selected as a working strain, and the yeast needs to be activated before inoculation. As can be seen from figure 4, with the gradual increase of the yeast inoculation amount, the alcoholic strength of the fruit wine is also gradually increased; however, after the inoculation amount of the yeast is continuously increased along with the increase of the inoculation amount of the yeast over 400mg/L, the harmful products of metabolism are gradually accumulated, the energy source and the growth space are limited, the growth and the propagation of the yeast are gradually limited, and the alcoholic strength of the fruit wine is gradually reduced.

2. Orthogonal experiment

Designing a four-factor three-level orthogonal experiment according to the single-factor experiment result, and determining the optimal process conditions by taking the alcoholic strength, the methanol and fusel oil content and the sensory score as target factors. Wherein the sensory evaluation score is: weighting each index, wherein the weight is as follows: color of 25%, texture of 15%, flavor of 30%, and taste of 30%, to obtain total score of sensory evaluation. See tables 1-3 for specific experimental setup and results.

TABLE 1 organoleptic scoring criteria for noni wine

TABLE 2 orthogonal experiment factor horizon

Factors of the fact	Level-1	Level 0	Level 1
				PH	6.5	7.0	7.5
Sugar content (g/L)	180	200	220
				Yeast inoculum (mg/L)	350	400	450
Fermentation temperature (. Degree.C.)	24	26	28

TABLE 3 results of orthogonal experiments

As can be seen from table 3, the sensory scores of the experimental groups 7 to 9 (pH = 7.5) are all low, and may be strong in alkalinity, the phenolic substances contained in the fruit wine change color, the transparency of the wine body is reduced, the taste is not fresh, and the added alkaline reagent is large in amount, so that the alkaline taste is aggravated, and the sensory score is remarkably reduced; along with the rise of the temperature, the content of the methanol and the fusel oil is increased, which is not beneficial to the safety of the product. The influence of all conditions on the alcoholic strength, the content of methanol and fusel oil and sensory score is integrated, and the optimal fermentation conditions are determined as follows: the pH =7.0, the sugar content of the clear juice of the fruit juice is 200g/L, the fermentation temperature is 24 ℃, and the yeast inoculation amount is 450mg/L.

Experimental example 2 influence of different deacidification modes on fruit wine quality

Reference example 1 a method for preparing fermented noni wine, except that while pH was adjusted by an alkaline agent in step S2, pH was adjusted to 7.0 by using different alkaline agents or addition means (see table 4), a series of fermented noni wines were prepared, and the contents of methanol and fusel oils, sensory scores and long-term stability results of the wines at the end of fermentation were measured, and the results are shown in table 5.

Wherein, the long-term stability experiment is as follows: placing the fruit wine at 25 + -2 deg.C and relative humidity of 60 + -10% for 12 months, sampling every 3 months, respectively sampling at 0, 3, 6, 9, and 12 months, and examining alcoholic strength and sensory condition.

TABLE 4 different ways of adjusting the pH

TABLE 5 fruit wine methanol + fusel oil and sensory scores and Long-term stability

Group of	Methanol + fusel oil (mg/L)	Sensory scoring	Long term stability
				1	704	56.0	Precipitation and remarkable discoloration and off-flavor in 3 months
2	897	57.5	Precipitation and remarkable discoloration and off-flavor appear in 6 months
				3	686	55.0	Precipitation and remarkable discoloration and off-flavor appear in 6 months
4	585	65.0	Precipitation and remarkable discoloration and off-flavor appear in 6 months
				5	323	87.5	Each index is basically kept unchanged
6	672	75.0	Precipitation and remarkable discoloration and off-taste in 9 months
				7	578	77.5	Precipitation and remarkable discoloration and off-taste in 9 months
8	553	67.5	Precipitation and remarkable discoloration and off-flavor appear in 9 months

As can be seen from table 5, the fruit wine prepared by the acidity adjustment method in which the alkaline agent is added at one time in groups 1 to 4 has different degrees of alkaline taste, low sensory score, higher methanol and fusel oil content and low safety; the fruit wine in 3-6 months has precipitation, obvious color change and taste change and poor stability. Group 5 contained less methanol + fusel oil, and did not cause discomfort symptoms to human body, and had high sensory evaluation and good stability. In groups 6-8, alkaline reagent is added step by step, but the unique fragrance of noni is weak, the fruit wine in 9 months has precipitation, remarkable discoloration and taste change, and the stability is not high.

Experimental example 3 quality testing of fruit wines of examples 1-6

1. Physical and chemical index detection

Physical and chemical indexes such as alcoholic strength, total sugar and total acid of the fruit wine prepared in the embodiments 1-6 of the invention are detected by referring to a general test method of GBT 15038-2006 wine and fruit wine, and the detection results are shown in Table 6.

TABLE 6 fruit wine physicochemical indexes in examples 1 to 3 of the present invention

2. Sensory Scoring determination

100 volunteers were selected and the wines from examples 1-6 prepared according to the invention were subjected to sensory evaluation, with the scoring criteria referenced in Table 1 and the results in Table 7.

TABLE 7 sensory evaluation results

Item	Color	Fragrance	Clarity of the product	Taste of the food	Total score
						Example 1	21.3	26.0	12.7	27.5	87.5
Example 2	20.5	25.6	12.4	26.5	85.0
						Example 3	19.8	25.4	12.8	25.5	83.5
Example 4	20.5	27.4	12.6	27.3	87.8
						Example 5	20.5	26.1	11.1	27.4	85.1
Example 6	20.3	25.8	11.6	26.1	83.7

As can be seen from Table 7, the fruit wines prepared in examples 1-6 of the present invention have high scores of all indexes, are very popular with volunteers, and have good sensory evaluation.

Experimental example 4 Long-term stability experiment

The fruit wine prepared in the examples 1-6 is placed at 25 +/-2 ℃ and the relative humidity of 60 +/-10% for 12 months, the sampling is carried out once every 3 months, the sampling is carried out at 0, 3, 6, 9 and 12 months respectively, and the physical and chemical indexes and the sense organ of the fruit wine are examined, so that the results show that the indexes of the fruit wine prepared in the examples 1-6 are basically kept unchanged after the fruit wine is placed at the specific conditions for 12 months, and the fruit wine meets the national standard regulation of food safety of GB2758-2012 fermented wine and wine prepared by the fermented wine.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.

Claims

1. A preparation method of fermented noni fruit wine is characterized by comprising the following steps:

s1, preparing noni fruit into clear juice;

s2, adjusting the sugar content of the clear juice obtained in the step S1 to be 100-220g/L, adding 5-15g/L calcium carbonate into the clear juice, mixing uniformly, naturally settling for 1-2 days, adding 2-8g/L potassium bicarbonate into siphoned supernatant, mixing and dissolving, detecting the pH =6.0-7.5, and standing overnight to obtain the product;

s3, pasteurizing the juice clear juice adjusted in the step S2 at 60-80 ℃ for 20-30min, cooling to 35-40 ℃, inoculating activated yeast with the inoculation amount of 350-500mg/L, and fermenting at 24-28 ℃ for 5-10 days;

the carbon dioxide-cooperated ultrahigh pressure sterilization method in the step S4 comprises the following steps: the volume ratio of the carbon dioxide to the fruit wine is 0.80-1.50, the pressure is 100-1000MPa, the temperature is 10-35 ℃, and the sterilization is carried out for 10-60 min.

2. The method according to claim 1, wherein the sugar content of the clear juice in the step S2 is 100 to 200g/L.

3. The method of claim 1, wherein 0.5-3g/L ammonium sulfate is added before the calcium carbonate is added in step S2.

4. The method according to claim 1, wherein the yeast in step S3 is one or two selected from the group consisting of LV yeast and Angel high activity dry yeast.

5. A fermented noni wine prepared by the preparation method according to any one of claims 1 to 4.

6. A fermented noni fruit wine prepared by the preparation method according to any one of claims 1 to 4, wherein the clear noni fruit juice obtained in step S1 is mixed with other clear fruit juice to obtain mixed clear fruit juice, and then the subsequent operations are carried out.

7. The fermented noni fruit wine according to claim 6, wherein the mixing volume ratio of the noni fruit juice clear juice to the other juice clear juice is 1 (1-4).