Protein and fat in milk are easily decomposed by bacteria, and expired milk may contain a lot of bacteria, such as Escherichia coli and Salmonella, which will do harm to human health. In addition, expired milk is also prone to odor and deterioration, and the taste will also be affected.

Therefore, in order to ensure health and safety, it is recommended not to drink expired milk. If you are not sure whether the milk has expired, you can judge by observing the appearance, smell and taste of the milk. If milk is found to have an odor, deterioration, thickening, etc. , should be discarded in time, not drinkable.

Matters needing attention in purchasing milk

1. Shelf life: Choose milk with long shelf life to ensure that the quality and nutrients will not decrease with time.

2. Brand reputation: choose milk produced by well-known brands or reputable manufacturers, and don't buy milk produced by unqualified small manufacturers.

3. Ingredients: Look carefully at the ingredients list of milk and choose milk with fat content suitable for your needs.

4. Packaging: undamaged and intact packaging should be selected, and packaging made of environmentally friendly materials should be selected as far as possible.

5. Preservation method: after purchase, it should be preserved according to the instructions on the package, and it should be drunk or refrigerated as soon as possible to ensure that the quality and nutrients of milk will not be reduced.