Soybean oil is an oil extracted from soybean, which has a certain viscosity and is a translucent liquid. Its color varies with soybean seed coat and soybean variety, from light yellow to dark brown, with soybean flavor. Soybean oil is widely used, and people have been processing soybean oil with soybean for a long time. The main component of soybean oil is triglyceride, and it also contains a small amount of phosphorus ester, sterol and other components. Triglycerides contain oleic acid (2 1.3%), linoleic acid beans (54.5%), linolenic acid and stearic acid (3.5%), palmitic acid (1 1.7%) in saturated fatty acids, and a small amount of wood acid and peanut acid. The calorie of one gram of soybean oil is about 9386 calories, and the digestibility is as high as 98.5%. The acid value of soybean oil is generally below 4.0mgKOH/g, the saponification value is 190 ~ 195 mg KOH/g, the freezing point is-150 ~- 190 c, and the iodine value is120 ~/kl. Among them, the content of vitamin E is the highest. As a kind of oil with high nutritional content and rich sources, soybean oil is loved by people all over the world because of its high quality and low price.

Second, the use of soybean oil.

(1) Edible

1, edible oil. Edible oil is the main way of soybean oil consumption. Worldwide, the consumption of cooking soybean oil accounts for about 70% of the total consumption of soybean oil. Domestically, the consumption of cooking soybean oil accounts for about 78% of soybean oil consumption and 35% of total oil consumption. Together with rapeseed oil, it has become two major edible oils in China.

2. Food processing. Soybean oil can not only be eaten directly, but also be used for food processing. Soybean oil can be used to make a variety of edible oils, such as cold oil, frying oil, shortening and so on. In addition, soybean oil is also used to make margarine, mayonnaise and other foods. The oil consumption for food processing in China accounts for about 12% of the total consumption of soybean oil. Due to different dining habits, the proportion of western countries is higher than that of China. For example, the oil consumption for food processing in the United States accounts for more than 25% of the total domestic soybean oil consumption.

(2) Industry and medicine

After deep processing, soybean oil is widely used in industry and medicine. In industry, soybean oil can be processed into glycerol, ink, synthetic resin, coating, lubricating oil, insulating products and liquid fuel. Stearic acid in soybean oil fatty acid can be used to make soap and candles; Soybean oil mixed with tung oil or linseed oil can make a good paint. In medicine, soybean oil has the functions of lowering blood cholesterol and preventing and treating cardiovascular diseases, and is an important raw material for making linoleic acid pills and yishouning.