Soybean oil is derived from soybean seeds, which are the most productive oils in the world.
The color of soybean hair varies depending on the soybean seed coat and the variety of soybean. Generally light yellow, slightly green, dark brown and so on. Refined soybean oil is light yellow.
Physicochemical constants of soybean oil:
Relative density (d20°C4°C) 0.9150-0.9375
Refractive index (n20°CD) 1.4735-1.4775
Viscosity (E020°C) Around 8.5 Freezing Point (°C) -18～ -15
Iodine value (g iodine/100g oil) 120-137
Saponification value (mgKOH/g oil) 188-195
Total fatty acid content (%) 94.96
Fatty acid average molecular weight 290 or so
Fatty acid composition of soybean oil
Ingredient content (%) Ingredient content (%)
Palmitic acid 6-8 oleic acid 25-36
Stearic acid 3-5 Linoleic acid 52-65
Arachidonic Acid 0.4-0.1 Linolenic Acid 2.0-3.0
Soybean oil has a savory taste, which can be removed after refining, but there is a tendency to taste after storage. Due to the presence of linolenic acid and iso-linoleic acid, the soybean meal flavor can be eliminated by the method of selective hydrogenation to minimize the linolenic acid content and avoid the formation of different linoleic acid.
When the refined soybean oil is stored for a long period of time, its color will become darker and darker. This phenomenon is called "color restoration." The recovery of soybean oil color is more significant than other oils, and the complex changes caused by the automatic oxidation of oil may be the basic reason. The method of reducing the moisture content of raw materials can prevent the occurrence of this phenomenon. This method is widely used and basically solves the adverse changes in the "response" of the color of soybean oil.
Soybean oil contains a large amount of linoleic acid. Linoleic acid is an essential fatty acid that has important physiological functions. Children lack linoleic acid, the skin becomes dry, scaly thickening, development and growth retardation; lack of linoleic acid in the elderly, can cause cataracts and cardiovascular and cerebrovascular disease.
The digestibility of soybean oil is 98%. The oil is also rich in vitamin E and A, so its nutritional value is high. Soybean oil is used in large quantities for cooking and making margarine. Soybean oil is used industrially as a raw material for paints, inks, high-grade lubricating oils, artificial butter, artificial wool, artificial fibers, and pharmaceutical supplements. Soybean oil also has antiseptic properties and can be used as a substitute for tung oil and linseed oil.