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.
If a sweeter fortified wine is desired, then the neutral grape spirits are typically added within the first day and a half of fermentation. Once this additional alcohol is added to the still base wine, the yeast stop converting sugar to alcohol and all of the remaining grape sugar is left in the wine as residual sugar.