No, yogurt is not expired milk. While both yogurt and milk are dairy products, they are different products that are made using different methods.
Milk is a liquid that is produced by mammals and is commonly consumed as a beverage or used in cooking and baking. Milk is often pasteurized to kill any harmful bacteria, which can extend its shelf life. However, even pasteurized milk will eventually spoil and develop a sour taste and unpleasant odor.
Yogurt, on the other hand, is a fermented milk product that is made by adding specific bacterial cultures to milk. These bacteria convert lactose, a sugar found in milk, into lactic acid, which thickens and sours the milk. The resulting product is a thick, tangy, and creamy substance that can be flavored or enjoyed plain.
One of the benefits of making yogurt is that the fermentation process extends the shelf life of the milk. The bacteria in the yogurt help to preserve the milk by producing lactic acid, which creates an acidic environment that inhibits the growth of harmful bacteria. This allows yogurt to stay fresh longer than plain milk.
While yogurt is made from milk, it is not the same as expired milk. Expired milk is milk that has gone bad and is no longer safe to consume. When milk goes bad, it develops a sour smell and taste due to the growth of bacteria. It may also develop mold or curdle, which means that the milk has separated into lumps and liquid.
In contrast, yogurt has a tangy and slightly sour taste that is intentional and desirable. The bacterial cultures used to make yogurt are carefully selected to produce a specific flavor and texture. When yogurt goes bad, it will start to smell and taste off, but it is unlikely to make you sick as the beneficial bacteria in yogurt usually dominate and suppress the growth of harmful bacteria.
In conclusion, yogurt is not expired milk. While both yogurt and milk are dairy products, they are different products made using different methods. Yogurt is made by adding bacterial cultures to milk, which ferments and thickens the milk into a tangy and creamy substance. Unlike expired milk, yogurt is a safe and healthy food that has a longer shelf life due to the beneficial bacteria it contains.