Organic compounds consisting of three fatty acid molecules and one glycerol molecule exist in subcutaneous tissues of humans and animals and in plants. Fat is a substance that stores energy in living things.
The fat in food is mainly fat. Generally speaking, liquid at room temperature is called oil, and solid at room temperature is called fat. Fat is composed of three elements, C, H and O. Fat is a triacylglyceride composed of glycerol and fatty acids, in which the molecule of glycerol is relatively simple, but the types and lengths of fatty acids are different.
Extended data:
Lipids in the human body are divided into two parts, namely fat and lipid. Fat, also known as true fat, neutral fat and triglyceride, consists of one molecule of glycerol and three molecules of fatty acids. Fat includes unsaturated and saturated. Animal fat contains saturated fatty acids and is solid at room temperature.
On the contrary, vegetable oil contains more unsaturated fatty acids and is liquid at room temperature. Lipids refer to cholesterol, cephalin, lecithin, etc. Its comprehensive functions are as follows: fat is a good energy storage substance in cells, which mainly provides heat energy; Protect internal organs and maintain body temperature; Assist the absorption of fat-soluble vitamins; Participate in metabolic activities in all aspects of the body and so on.
The sources of fat can be divided into the following two types:
1. Animal origin: fats stored in animals: such as lard, butter, sheep oil, fish oil, bone marrow, fat meat, cod liver oil, etc. Fat in animal milk: such as cream.
2. Plant source: Plant fat is mainly extracted from fruits in plants, such as sesame seeds, sunflower seeds, tea seeds, walnuts, pine nuts and soybeans.
The main sources of fat are cooking fat and the fat contained in food itself. Table 5 shows the fat content in several foods. As can be seen from the figures in the table below, the fat content of nuts is the highest, all kinds of meat are in the middle, and the content of rice, flour, vegetables and fruits is very small.
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