As far as fermenting time goes, for bowls of yogurt I like to ferment 8 hours. Any longer and my kids say it's too sour. For smoothies, they can tolerate the 24-hour tangy yogurt. I sweeten it up by blending it with frozen bananas and strawberries. When my yogurt is all done, I store it in a half gallon mason jar with a plastic lid. It will keep for two weeks.