JPS6343078B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing high-quality grape wine that is rich, mellow, and has a stable color tone. Traditionally, grape wine is generally made by adding potassium metabisulfite, isomeric potassium bisulfite, or sulfurous acid to the grape juice obtained by destemming raw material grapes, crushing them, and pressing them to prevent browning due to oxidation or suppress the growth of harmful microorganisms. It is produced by adding sake mash to the fermented product, fermenting it, then slaging and sieving it, and then aging it. The quality of grapes as a raw material is the most important factor in the production of wine, and the quality of the wine is greatly influenced by its sugar content, aroma and flavor. Currently, the fruit juice obtained from grapes grown in our country has too low a sugar content to be used as a raw material for wine, so supplementation by adding sugars such as sugar or glucose is generally performed before or during fermentation. It is. However, grape wine produced using sugar-enriched grape juice as a raw material lacks rich aroma and flavor, making it extremely difficult to obtain high-quality wine from sugar-enriched grape juice. be. Incidentally, the raw material grapes for wine grown in our country, such as Koshu, Delaware, and Muscat Berry A, are similar to the raw material grapes of European countries such as Semillon, Chardonnay,
Compared to Riesling, Cabernet Sauvignon, etc., grapes have a flat and weak aroma and flavor, which is also a major obstacle in producing high-quality wine in our country. In recent years, in view of the lack of sugar content in the raw material grape juice in our country as mentioned above, a method has been considered to increase the sugar content by concentrating grape juice and enhance its aroma and flavor. Freeze concentration is a method for concentrating grape juice. methods and reverse osmosis membrane concentration methods have been proposed. However, among these concentration methods, the freeze concentration method has disadvantages such as poor concentration efficiency and high energy cost for freezing.
Although the reverse osmosis membrane concentration method has the advantage of low energy costs, it has the following important drawbacks. Firstly, the most important aroma for grape wine, especially the aroma derived from grapes, changes or sometimes decreases, making it impossible to produce grapes with a rich aroma using the normal reverse osmosis membrane concentration method. . Second, the stirring action of the grape juice caused by the juice circulation during concentration promotes oxidation and browning of the fruit juice, resulting in a loss of freshness of the fruit juice. Therefore,
Grape wine produced from such fruit juice has undesirable oxidation odor and coloration, resulting in grape juice with poor freshness. As mentioned above, concentrating fruit juice using the normal reverse osmosis membrane concentration method has an unfavorable effect on the production of grape bottlings, so it is difficult to produce high-quality grape bottlings simply by concentrating raw grape juice using a reverse osmosis membrane. I can't. In view of the current situation, the present inventors have made it possible to increase the sugar content and enhance the aroma and flavor of raw grape juice without deteriorating its quality, thereby producing rich and mellow high-quality grape juice. As a result of considering the method, it was found that the above-mentioned high level can be achieved by using a blend of two types of fruit juice obtained by concentrating raw grape juice using two types of reverse osmosis membranes with different salt rejection rates at a constant ratio as raw fruit juice. The inventors discovered that it is possible to produce high-quality grape wine, leading to the present invention. The present invention will be explained in detail below. The features of the present invention include a reverse osmosis membrane that has a salt removal rate of 70 to 95% and a reverse osmosis membrane that has a salt removal rate of 96 to 99% when producing grape wine by fermenting grape juice with a yeast mother. Two kinds of fruit juices having a sugar content of 24 to 35% (fruit juice A) and 20 to 25% (fruit juice B) are prepared by concentrating them using a membrane, respectively, and these two fruit juices are added to the above fruit juice to the above fruit juice A. B at least
The purpose is to produce grape wine by blending 10% volume and using the blended juice obtained in this way as a raw material. The raw material grapes used in the present invention may be any grapes that are normally used in the production of wine; fully ripe grapes with a high sugar content are preferable because the juice can be concentrated in a short time, but unripe grapes with a low sugar content Or, there is no problem even if the grapes are from a bad year due to unseasonable weather. The preparation of fruit juice from the raw material grapes is done by destemming the raw material grapes using a conventional method, then crushing and pressing the resulting fruit juice, adding potassium metabisulfite (or isomeric potassium bisulfite or sulfurous acid), removing insoluble matter, and clarification. Obtain fruit juice. Clarification of this fruit juice is carried out using a combination of sedimentation method and pressurized filtration method using super-aids such as diatomizers and asbestos, or centrifugation method. This is done to prevent clogging and improve concentration efficiency.Next, the clarified juice prepared in this way is divided into two sections, and one of the juices is divided into two sections with a salt rejection rate of 70 to 95%.
Concentrate the fruit juice to a sugar content of 24-35% using a reverse osmosis membrane with a salt removal rate of 96-99%. . The "salt rejection rate" here refers to the membrane permeate that is measured 30 minutes after pressurization when 0.5% salt solution is subjected to membrane treatment at 25°C and under a pressure of 42 kg/ ^cm2 . Calculated from the amount of salt. In other words, the lower the amount of salt in the membrane permeate, the higher the salt rejection rate. In the present invention, two types of concentrated fruit juices are prepared using two types of membranes with different salt rejection rates as described above,
The reason why a blend of these is used as raw fruit juice is as follows. First, concentrated fruit juice A with a sugar content of 24-35%, which is obtained by concentrating raw fruit juice using a reverse osmosis membrane with a salt rejection rate of 70-95%, is a fruit juice with a sugar content sufficient to match the alcohol concentration of grape wine. The purpose is to enrich the flavor of the resulting grape wine, and if a membrane with a salt rejection rate of less than 70% is used in the preparation of concentrated fruit juice, acids, ash, and free amino acids may have a large effect on the flavor. On the other hand, if the salt exclusion rate is higher than 95%, the desired sugar content cannot be obtained in a short time. However, since concentrated fruit juice A alone lacks aroma, concentrated fruit juice B with a sugar content of 20 to 25% is prepared separately using a membrane that exhibits a salt rejection rate of 96 to 99%. That is, by concentrating grape juice using a membrane with a salt rejection rate of 96 to 99%, the aroma of the fruit juice is retained, and as a result of the concentration, it becomes possible to obtain fruit juice B that has particularly enhanced not only the aroma but also the flavor. . However, in order to obtain this fruit juice B, it takes a long time to raise the sugar content to 25% or more because the salt rejection rate of the membrane is extremely high.Therefore, it is difficult to produce grape wine using only this fruit juice. is not a good idea. Therefore, in the present invention, fruit juice suitable for producing high-quality grape wine is prepared by blending fruit juice A with a high sugar content with fruit juice B with a high aroma at 10% by volume or more. Next, the results of testing the relationship between the salt rejection rate of the membrane used for concentrating grape juice and the quality of wine produced using the concentrated fruit juice are shown below. Test method: Take 500 g of fruit juice (sugar content 15.2%) from Koshu grapes, add potassium metabisulfite (or 50 g of isomeric potassium bisulfite), leave for 15 hours to precipitate insoluble matter, and then extract the supernatant juice. The clarified fruit juice was filtered using asbestos as a super-aiding agent to obtain 450 ml of completely transparent clarified fruit juice.Next, 25 of the clarified fruit juices were filtered to reduce the sugar content using 5 types of reverse osmosis membranes with different salt rejection rates made by the same manufacturer. Each was concentrated to 25.0%, and the obtained 5
15 portions of concentrated seed juice were placed in 20-sized bottles.
The membranes used each have a membrane area of 0.74 m ² , and the concentration conditions are a membrane outlet pressure of 50 to 60 Kg/cm ² and a fruit juice temperature of 12
The test was carried out at a flow rate of 350 to 400/hour at a temperature of 350 to 400 °C, and the inside of the fruit juice tank was maintained in a mixed gas atmosphere of N ₂ :CO ₂ =1:1. The concentration processing time is based on the salt rejection rate of the membrane used: 50,
120 minutes each according to 70, 90, 95 and 98%,
It took 120, 150, 170 and 180 minutes. 500 ml of grape juice culture of grape wine yeast (strain of Saccharomyces cerevisiae) was added to each concentrated fruit juice obtained as described above, and the mixture was incubated at 15°C for 20
Fermented for a day. After the completion of fermentation, 3 g of potassium metabisulfite (or isomeric potassium bisulfite) was added to each fermented liquor, followed by sloughing and straining according to conventional methods, and aging for 6 months to produce new sake. The results of analysis and sensory evaluation of each new sake obtained are shown in Tables 1 and 2 below. The sensory evaluation was conducted by 15 panelists in accordance with the Quality Judgment Method of the International Grape and Liquor Fair, and the color tone was 0 to 0.
2 points for clarity, 0 to 2 points for aroma, 0 to 4 points for aroma, and 0 to 12 points for flavor and overall evaluation, and the average value was expressed.

[Table] ** Displayed as acidity of tartaric acid
＊＊＊ Measured with an automatic amino acid analyzer

[Table] As shown in Tables 1 and 2 above, wine produced from fruit juice concentrated with a membrane with a salt rejection rate of less than 70% has poor aroma and flavor. On the other hand, the salt exclusion rate is 96
% or more of fruit juice concentrated with a membrane has a significantly superior aroma. Next, using Koshu grape juice, the salt elimination rate is 92%.
Grape wine was produced as described above by blending fruit juice A concentrated using a membrane with various volume percentages of fruit juice B concentrated using a membrane with a salt rejection rate of 98%. Table 3 shows the results of quality evaluation.

[Table] As shown in Table 3 above, add fruit juice B to fruit juice A.
Grape wine produced using blended fruit juice of 10% or more by volume has excellent aroma and flavor. In the present invention, it is preferable to concentrate the fruit juice using the membrane in an atmosphere of an inert gas, such as nitrogen gas, carbon dioxide gas, or a mixture of both, and at a temperature of 7 to 15°C. The purpose of this is to prevent as much as possible the oxidation of the fruit juice due to contact with air, and to prevent the fruit juice from deteriorating due to the increase in the temperature of the fruit juice due to repeated circulation under high pressure during the concentration process. In particular, in the concentration method using a reverse osmosis membrane, the fruit juice is circulated at high pressure, so shearing force acts at the outlet, which is kept at normal pressure, and air entrainment increases, causing oxidative browning. Furthermore, the optimal temperature for membrane concentration of fruit juice is in the range of 7 to 15°C; if the above temperature is lower than 7°C, a large amount of potassium tartrate crystals in the fruit juice will precipitate during concentration. This can clog the reverse osmosis membrane and reduce concentration efficiency, while if the temperature is higher than 15°C, there is a risk of browning of the fruit juice, which in turn will deteriorate the color tone of the wine. The reverse osmosis membrane used in the present invention is not particularly limited as long as it exhibits the above-mentioned salt rejection rate, and any commercially available membrane may be used. To produce grape wine from the blended juice of fruit juice A and fruit juice B obtained by membrane concentration as described above, according to the conventional method, wine yeast is added and fermented, and after fermentation is completed, the slag is removed, It is done by going through a period of time to mature. In addition, upon fermentation of the fruit juice, grape skins and seeds (namely, pressed lees of raw material grapes) can be added to the fruit juice, and then the yeast can be added and fermented. As described above, the present invention has the remarkable advantage that even when grapes with relatively low sugar content are used as raw materials, high-quality wine with extremely good aroma and flavor can be produced. Examples are illustrated below. Example 1 After adding 25g of metabisulfite (or isomeric potassium bisulfite) to 170% fruit juice (sugar content 15.8%) colored by a conventional method from Koshu grapes, the juice was pressure-filtered using asbestos to obtain 150% A clear fruit juice was obtained. Of these, 120 clarified fruit juices are concentrated using a reverse osmosis membrane that has a salt removal rate of 92%, resulting in a fruit juice with a sugar content of 26.0%.
Got A65. The concentration conditions at this time are membrane area
3.2 m ² , outlet pressure 50-60 Kg/cm ² , flow rate 600/hour, juice temperature 12°C, and 240 minutes were required for concentration. Note that the inside of the fruit juice tank was replaced with a mixed gas of N ₂ :CO ₂ =1:1 to create an inert atmosphere. On the other hand, the remaining clarified fruit juice 30% was concentrated for 110 minutes using a reverse osmosis membrane with a salt rejection rate of 98%, resulting in a sugar content of 22.0.
% fruit juice B21 was obtained. The concentration conditions at this time were the same as above except that a membrane with a membrane area of 1.6 m ² was used. Add fruit juice to fruit juice A25 obtained as described above.
The fruit juice blended with B5 was fermented and aged according to conventional methods, and after 6 months, the sensory evaluation of the resulting grape wine was conducted by a panel of 15 people in accordance with the Quality Judgment Method of the International Grape Liquor Competition. The results are shown in Table 4. For comparison, the results of a similar sensory evaluation of the grape wine obtained after 6 months of fermentation and aging using only fruit juice A30 in the same manner as above are also shown in Table 4. Evaluation: color tone 0-2 points, clarity 0-2 points, aroma 0 points
-4 points and flavor 0-12 points, total score out of 20,
Expressed as an average value.

[Table] Example 2 Juice collected from Koshu grapes (sugar content 16.0%)
2100 was collected, 200g of potassium metabisulfite (or isomeric potassium bisulfite) was added to it, and 15
I left it for a while. The obtained supernatant juice was passed through a centrifuge to continuously remove insoluble matter to obtain clarified fruit juice 2000. Of these, 1500 was concentrated to a sugar content of 26.0% using a reverse osmosis membrane with a salt removal rate of 92% to obtain 900 fruit juice A. The concentration conditions at this time are membrane area 10.0
m ² , outlet pressure 60 Kg/cm ² , flow rate 700/hour, and juice temperature 12° C. The juice was divided into 500 portions and concentrated three times. The total time required for this concentration was about 6 hours. On the other hand, the salt removal rate for the remaining clarified fruit juice 500% is 98%.
The sugar content is concentrated to 22% using a reverse osmosis membrane that shows
380 fruit juice B was obtained. This concentration required 150 minutes.
Further, the concentration conditions at this time are the same as above. In addition, when concentrating both of the above, the inside of the fruit juice tank is
The atmosphere was replaced with a mixed gas of N ₂ :CO ₂ =1:1 to maintain an inert atmosphere. The fruit juice B380 thus obtained was blended with the above-mentioned fruit juice B900, 20 pieces of fruit juice culture of a strain of Saccharomyces cerevisiae, which is a wine yeast, was added thereto and fermented at 150°C for 20 days. After completion of fermentation, processing was carried out according to conventional methods, and the new sake obtained after aging for 6 months was analyzed and sensory evaluated (according to Example 1). The results are shown in Tables 5 and 6. For comparison, the new sake obtained by fermenting fruit juice 1280, which was obtained by adding sugar to the clarified fruit juice taken from the same grapes as above to bring the sugar content to 26.0%, was fermented in the same way, and then aged for 6 months. Similarly, the results of analysis and sensory evaluation are also shown in Tables 5 and 6.

【table】

[Table] Example 3 Juice collected from Semillon grapes (sugar content
15.8%) 100 is made into clarified fruit juice using a centrifuge,
Of these, 70 are reverse osmosis membranes with a salt rejection rate of 90%, and 20 are with a salt rejection rate of 98%, each with a sugar content.
26.0% (obtained fruit juice amount 42), 21.0% (obtained fruit juice amount
15). The two types of fruit juices obtained were mixed and mixed with grape wine yeast (Saccharomyces cerevisiae).
strain) was added and fermented at 20°C for 14 days. After fermentation, the grapes were treated in the usual way and after 6 months of aging, the grapes were evaluated. As a result, a rich and mellow wine with a very strong aroma and firm body was produced. Example 4 Muscat berry type A grape (sugar content 16.0%)
After destemming 100kg, crush and press to collect 65% of juice.
This was made into clarified fruit juice using a centrifuge. Of these, 45 have a salt rejection rate of 90%, and 20 have a salt rejection rate of 98%.
The sugar content was concentrated using a reverse osmosis membrane to 25.0% and 22.0%, respectively. The amount of juice at this time is 27 and 27, respectively.
It was 13. Next, pressed lees discarded during pressing was added to the mixed fruit juice of these two types, and fruit juice culture solution 1 of grape wine yeast (a strain of Saccharomyces cerevisiae) was added, followed by fermentation at 25°C. Two days later, the juice was pressed and fermented at 25°C for another 14 days. After fermentation, the grapes were processed in the usual manner and evaluated after 6 months of aging. The results showed that the grapes were very aromatic and had a rich and well-balanced acidity and astringency, producing an excellent wine. was completed.

Claims (1)

[Scope of Claims] 1 Grape juice is concentrated using a reverse osmosis membrane that exhibits a salt rejection rate of 70 to 95% to prepare concentrated fruit juice A having a sugar content of 24 to 35%, while grape juice has a salt rejection rate of 96%.
Concentrated using reverse osmosis membrane showing ~99% sugar content ~20~
25% concentrated fruit juice B is prepared, the concentrated fruit juice B is blended with the concentrated fruit juice A at least 10% by volume, and the resulting blended concentrated fruit juice is then fermented by a conventional method. Manufacturing method. 2. The method for producing grape wine according to claim 1, wherein the concentrated fruit juice is prepared in an inert gas atmosphere. 3. The method for producing grape wine according to claim 1 or 2, characterized in that the concentration of grape juice using a reverse osmosis membrane is carried out while maintaining the temperature of the fruit juice in the range of 7 to 15°C. .