Pure organosilicon, such as dimethyl silicone oil, has no defoaming effect. However, after emulsifying, the surface tension decreases rapidly, and the use of a very small amount can achieve strong anti-foaming and anti-foaming effect, becoming an important component of anti-foaming agent. Silicone oil defoaming agent generally has high defoaming efficiency, the key to its use lies in the emulsification of silicone oil. If the emulsification is not complete, the use of demulsification, affecting its use effect. The commonly used silicone defoaming agent, removing the strong defoaming force, is particularly valuable is siloxane set chemical stability, physiological inertia and high and low temperature performance in one, so it has been widely used. Because silicone oil itself is lipophilic, it has a satisfactory effect on the defoaming of oil-soluble solution.Organosilicone defoaming agent is a low toxicity, anti-oxidation, anti-foaming ability is strong defoaming agent, but its anti-foaming ability is poor, large consumption, poor effect on slightly acidic fermentation, mycelium development and has a certain inhibitory effect. Therefore, the application in fermentation industry is limited; In the textile printing and dyeing industry, especially the use of light-colored fabrics, because the silicon spot is not easy to wash and again restricted.