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.
Obviously this is a much slower stage in the process. Primary fermentation took three to five days and produced 70% of our alcohol while secondary fermentation takes up to two weeks just to get the last 30%.