What are the Types of Food Grade Defoamers and Their Classification Characteristics

Jan 8, 2021

1. Advantages of natural oils (i.e. soybean oil, corn oil, etc.): easy source, low price,
Simple to use; disadvantages: if the storage is not good, it is easy to deteriorate, so that the acid value increases, and it is toxic to fermentation.
2. There are many kinds of polyether defoamers, mainly including the following: A. GP defoamer: it is made by addition polymerization of propylene oxide or mixture of ethylene oxide and propylene oxide with glycerol as the starting agent. GP defoamer has poor hydrophilicity and low solubility in foaming medium, so it should be used in thin fermentation broth. Its antifoaming ability is superior to that of defoaming, and it is suitable to be added in the basal medium to inhibit the foaming process of the whole fermentation process. b. GPE defoamer: that is foam enemy, GP defoamer in the end of the poly (propylene glycol) chain segment and then add ethylene oxide, to form the end of the chain is hydrophilic group of polyoxyethylene oxypropylene. Allyl glycerin, also known as. According to the addition amount of ethylene oxide is 10%, 20% 50% are called gpe10, gpe20 GPE50。 GPE defoamer has good hydrophilicity, easy spreading in foaming medium, strong defoaming ability, high solubility and short duration of defoaming activity, so it has better effect in viscous fermentation broth. c. GPEs type defoamer: there is a new polyether type defoamer. The hydrophobic stearate is used to seal the end of GPE type defoamer chain to form a block copolymer with hydrophobic chain at both ends and hydrophilic chain in the middle. The molecules with this structure tend to gather at the gas-liquid interface in a horizontal manner, so they have strong surface activity and high defoaming efficiency.
3. High carbon alcohol is a kind of linear molecule with strong hydrophobicity and weak hydrophilicity, which is an effective defoamer in water system. It is found that the defoaming effect of alcohol is related to its solubility and diffusion in the foaming solution. C7 ~ C9 alcohol is the most effective defoamer. The high alcohols of C12~C22 are made up of suitable emulsifiers, which are made up of water emulsions with a particle size of 4~9 m and 20~50% content, that is, the defoamer of water system. Some esters, such as phenylethanolate oleate and lauryl phenylethanoate, have defoaming effect in penicillin fermentation, and the latter can also be used as precursors.
4. The most commonly used silicone is polydimethylsiloxane, also known as dimethylsiloxane. It has low surface energy, low surface tension, low solubility in water and general oil and high activity. Its main chain is a silicon oxygen bond, which is a non-polar molecule. It is not compatible with polar solvent water and has little affinity with general oil. It has low volatility, chemical inertness, stability and low toxicity. Pure polydimethylsiloxane is difficult to be used as defoamer without dispersion treatment. It may be due to its high interfacial tension with water and low spreading coefficient, so it is not easy to disperse on the foaming medium. Therefore, the complex formed by mixing silicone oil with SiO2 aerosol, that is, mixing hydrophobic treated SiO2 aerosol with dimethylsiloxane base silicone oil, can be prepared after a certain temperature and time treatment.
5. Polyether modified silicon was successfully developed and put into production in 2002. It combines the advantages of polyether and silicone defoamers. It is non-toxic and harmless, harmless to bacteria, and has few additives. It is a cost-effective product.

Food grade defoamer is a kind of defoamer in aqueous system, which is easy to disperse in water and easy to use. It has fast defoaming effect and anti foaming function in wide pH and temperature range. It has good compatibility with various auxiliaries. It can quickly eliminate foam and has the effect of preventing foam regeneration. It is mainly used for defoaming in food, starch plant and other special industries. It is also widely used in printing and pulping, bleaching and dyeing, biotin fermentation, water-based additives processing, papermaking, pesticide, washing, adhesive, ink coating, sewage treatment and other fields.

Water treatment defoamer is a kind of defoamer in water phase system, which is easy to disperse in water and easy to use. It has fast defoaming effect and anti foaming function in wide pH and temperature range. It has good compatibility with various auxiliaries. It can quickly eliminate foam and has the effect of preventing foam regeneration. In addition to good effect in food, it can also be widely used in printing and pulping, bleaching and dyeing, biotin fermentation, water-based additives processing, papermaking, pesticides, washing, adhesives, inks and coatings, sewage treatment and other fields.