Grapes hanging on the plant do not ferment but after being plucked from the plant can be fermented. Under what conditions do these grapes ferment? Is it a chemical or a physical change?
When grapes are still on plants, their self-defense mechanism is at work. This prevents fermentation of grapes. When grapes are plucked form plants, then yeast (a type of fungi) carry out fermentation. During fermentation, sugar changes into alcohol. So, it is a chemical change
