the feeling of a person whose attention, concern, or curiosity is particularly engaged by something: She has a great interest in the poetry of Donne. something that concerns, involves, draws the attention of, or arouses the curiosity of a person: His interests are philosophy and chess.
Primary fermentation usually takes between three to seven days to complete. It goes by much more quickly than secondary fermentation because wine must is a much more fertile environment for the yeast. Sugar and oxygen levels are high during primary fermentation and there are plenty of nutrients.
This air plays an important roll in the multiplication of the yeast cells. Here's how important. The little packets of yeast that is generally called for in a five gallon wine recipe will typically be multiplied up to 100 to 200 times during the few days of primary/aerobic fermentation. It is also important to understand that once the wine's fermentation activity has stopped that it also needs to be given time to clear as well before bottling. Yeast is a silty substance that can take up to 2-4 additional weeks to clear up once the fermentation has stopped.