Antifoaming agents
What is foam? A foam is a substance that is formed by trapping pockets of gas in a liquid or solid. A bath sponge and the head on a glass of beer are examples of foams. In most foams, the volume of gas is large, with thin films of liquid or solid separating the regions of gas.
Foam is a serious problem in the chemical industry, especially for biochemical processes. In general, the formation of stable foam causes problems in most industrial processes, affecting directly the quality of the final product, reducing the carrying capacity of containers or causing pumping problems, among others. In the processing of food and beverages such as sugar beet, orange and tomato juice, beer, wine and mashed potatoes, foaming problems caused by soluble proteins and starch are commonly encountered.
Antifoaming agents, also known as defoaming agents. These agents are chemical substances used to reduce foaming caused by proteins or gases, thus inhibiting, or modifying the formation of a foam, that may be interfere with processing. Foaming may be largely suppressed or completely eliminated by the use of small quantities, generally 10 ppm.
Generally, these agents have surface active properties and are insoluble in the foaming medium. These are less viscous, easily spreadable on the foamy surface, and possess affinity to the air–liquid surface where it destabilizes the foam lamellas, which rupture the air bubbles and break down the surface foam.
Some physical methods are also applied to remove foam such as temperature change, evaporation, freezing, sharp pressure change, centrifugal separation, ultrasonic wave, and filtration.
Antifoaming agents have been suggested for use in the preparation of certain comminuted meat products, bakery products, confections, dairy products, vegetable oils, alcoholic and nonalcoholic beverages, jams and jellies, molasses, soups, starches, syrups and pickles.
Classification:
*Oil based defoamers
*Powder defoamers
*Water based defoamers
*Silicone based defoamers
*EO / PO based defoamers
*Alkyl poly acrylates
Antifoaming agents
