Plain yogurt has a semisolid mass due to coagulation of milk(skim,low,or full fat)by starter-culture bacteria.it has a sharp acid taste with a flavor similar to walnuts and a smooth mouth feel. the flavor is due to the combined effects of acetaldehyde,lactate,diacetyl,and acetate,but 90 of the flavor is due to acetaldehyde.
many types of yogurt are available in the market,for example,plain yogurt,frozen yogurt,dried yogurt,low-lactose yogurt,and carbonated yogurt