After milk is frozen, the fat and protein are separated, and casein is concentrated into powder, so the taste of milk will be obviously weakened, and the nutrients are not easily absorbed.

Generally speaking, fresh milk is a milky white or yellowish uniform colloidal liquid, which has no precipitation, no clots, no impurities, no starch feeling and no peculiar smell, and has the inherent fragrance of fresh milk. If you pour milk into a cup and shake it, it is easy to hang on the wall; Drop a drop of milk on the glass, which is round and not easy to flow away; There are no clots and flocs after cooking.

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Tips for drinking milk:

1, don't drink milk on an empty stomach. Experts believe that milk and eggs are the best combination for breakfast, but some people only drink milk and don't eat other foods. Drinking milk on an empty stomach in the morning has many disadvantages. Because it is on an empty stomach, milk can't be fully hydrolyzed and nutrients can't be well digested and absorbed. Some people may also have symptoms such as abdominal pain and diarrhea. Therefore, it is best to eat something before drinking milk, or drink milk while eating, so as to reduce the lactose concentration and facilitate the absorption of nutrients.

2. Avoid drinking milk and tea together. Some people like to drink tea while drinking milk. In fact, this is an unscientific drinking method. Because milk is rich in calcium ions, tannic acid in tea will hinder the absorption of calcium ions in gastrointestinal tract and weaken the inherent nutrients of milk itself.

Baidu Encyclopedia: Experts remind you to drink milk correctly.