Skim milk here is relative to full-fat milk, and there is low-fat milk in between. The production of skim milk meets the nutritional needs of modern people to pursue "high protein and low fat". When the fat content of 100ml liquid milk and yogurt is ≤0.5g, or the fat content of 100g milk powder is ≤ 1.5g, it can be marked as "defatted".
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The fat content of whole milk is about 3%, low-fat milk (semi-skimmed milk) contains fat1.0 ~1.5%, and whole skimmed milk contains fat ≤0.5%.
For modern people, people not only rely on milk to supply energy, but often focus on the high-quality protein contained in milk, so they prefer low-fat milk with less fat to become skim milk. In recent years, all kinds of low-fat and skim milk products have been put on the shelves of shopping malls and supermarkets, and become a kind of healthy drink that people generally choose in their daily lives.
Baidu encyclopedia-skim milk