Process Raw material selection → sorting → de-stemming → purging → rinsing → crushing → main fermentation → pressing → post-fermentation → storage → clarification and filtration → bottling, sterilization 1. Raw material selection. Select grapes with colorful skins, and eliminate rotten, diseased and green fruits. Wash the surface with water to remove dirt.
2. Crushing, de-stemming. Available roller or centrifugal crushing of the fruit pressure broken, and then by the de-stemming machine to remove the fruit stalks, in order to make the wine taste soft. After crushing to remove the fruit stalks of the grape pulp, because it contains juice, peel, seeds and small fruit stalks, should be immediately sent to the fermentation pool, the fermentation pool should be left above the 1 4 gap, not full, in order to prevent floating in the pool surface of the skin groove due to the carbon dioxide produced by the fermentation and overflow.
3. fermentation. The grape pulp into the fermentation tank, until the main fermentation is completed that the new wine out of the pool this process is called fermentation. Fermentation before the need to adjust the sugar level, the amount of sugar generally to the original average sugar content of the grapes as a standard, the sugar should not be too much so as not to affect the quality of the finished product. In the grape pulp into the pool of sulfur dioxide will be added once, the fermentation process is no longer added, the amount according to the sugar, acidity and grapes in good condition, generally 20 ~ 40 grams per kilogram. After 2~3 hours, add the yeast liquid, add the amount of 5~10% of the pulp, add and stir well, so that the yeast is evenly distributed. Yeast reproduction and the absence of bacterial damage must be checked daily during fermentation. If the yeast growth is poor or less, should be re-added to the mother liquor. If there is any fungus damage, you should burn sulfur indoors and use sulfur dioxide to sterilize the fungus. The fermentation temperature must be controlled between 20~25℃.
The duration of the main fermentation varies according to the sugar content of the grapes, the fermentation temperature and the number of yeast inoculations. Generally when the specific gravity drops to about 1.020 can be out of the pool, transferred to the post-fermentation.
4. Post-fermentation. Post-fermentation pool or barrel to leave 5-15 centimeters of space above, because the post-fermentation will also generate foam. The temperature of the product during the post-fermentation period is controlled between 18~20℃, and the maximum should not exceed 25℃. When the specific gravity drops to about 0.993, the fermentation is over.
5. Aging. Bout brewing requires low temperature and good ventilation. Suitable aging temperature of 15 ~ 20 ℃, relative humidity of 80 ~ 85%. In addition to the aging period should maintain the appropriate temperature, humidity, should also pay attention to the barrel, add barrel.
The first barrel change should be carried out 8~10 days after the completion of fermentation, to remove the dregs, and at the same time add sulfur dioxide to 150~200 mg liter. The second bucket change is carried out 50~60 days after the previous bucket change. About three months after the second barrel change, the third barrel change, after three months and then the fourth barrel change.
In order to prevent the invasion and propagation of harmful bacteria, it is necessary to fill the empty space of the wine storage container at all times and keep its surface out of contact with the air. In the new wine into the barrel, the first month should be 3~4 days to add barrel once. In the second month, it should be added to the barrel once every 7-8 days, and then once every month, and for aged wine more than one year, it can be added to the barrel once every half a year. The wine used to add barrels must be clean, and it is best to use the same variety and quality of the original wine.
6. Blending. After 2~3 years of storage, the original wine has matured and aged, and has the aroma of old wine. It can be blended according to the variety, flavor and composition. The original grape wine should be more than 50%. Color: purplish red, transparent and without impurities. Taste: clear and mellow, sweet and sour.
Specific gravity: 1.035~1.055(15℃).
Alcohol: 11.5~12.5(15℃).
Total acid: 0.45~0.6g/100ml.
Total sugar: 14.5~15.5g/100ml. Volatile acid: less than 0.05 g/100 ml.
Tannin: 0.45~0.06g/100ml.
The prepared wine must be laboratory checked and filtered once before bottling and then capped. After sterilized at 75℃, it can be labeled and packaged for sale.