Because the brewing process of wine is a process of yeast fermentation, yeast will consume a lot of sugar and release carbon dioxide and alcohol at the same time, but it should be noted that wine should be properly ventilated during fermentation to avoid bottle bursting caused by too much carbon dioxide.
To prevent self-brewed wine from foaming, we should choose good grapes and fresh grapes before brewing, and pick out all rotten, moldy and cracked grapes to brew clean and complete good grapes.
When cleaning, it is best to wash the whole string, don't rub it by hand, don't brush it with a brush, and don't disinfect the grapes to ensure the survival of wild yeast. After the grapes are washed, put them in a basket to fully dry the water, or hang the whole bunch to dry.
To prevent homemade wine from foaming, the handling of utensils is also very important. It is best to use alcohol for sterilization and disinfection, so as not to stick to other fungi and affect the quality of wine. The wine jar can be a ceramic jar, a glass bottle or a plastic bottle.
Extended data:
Secondary fermentation:
The second fermentation will produce a small amount of fine foam, and the wine will be very clear after 2 ~ 3 weeks.
The second fermentation depends not on yeast fermentation, but on malic acid and lactic acid fermentation, so it will not produce a lot of carbon dioxide, the pressure in the bottle will not continue to rise, and there will be no danger of bottle explosion. So the container should be as full as possible and the bottle cap should be tightened. It is recommended not to add egg white to clarify (if it is stored for a long time, the taste is not fresh enough).
When it was opened twenty days later, it was found that the liquor became clear, and there was a layer of sediment at the bottom, which was the "corpse" and impurities of yeast after completing its historical mission. This layer is used in industry to make yeast puree. ?
The pure liquid on the upper layer is purified and filled by siphon or filtration. It's best to keep it in a small bottle. It's best to use 1.5 liter old wine bottle, and it's not bad to use 2.25 liter plastic bottle for coke. The bottle should be full, the cap should be tightly closed, and then it should be placed in a place with low temperature at home (it is said that 13℃ is the best storage temperature).
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