Читать книгу Food Chemistry. The Role of Additives, Preservatives and Adulteration онлайн

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They are also known as defoamer. They reduce and hinder the formation of foam in industrial processed liquid. They are classified as oil based, powder based, water based etc. When used, they reduce the effervescence in a preparation. Silicone oil is added in commercial cooking oil to prevent the froth formation in deep frying food.

They are also called improver or flour improving agent as they improve the baking functionality of flour. These agents are of following four types:

 a. oxidizing and reducing agent

 b. enzymes

 c. bleaching agents

 d. emulsifier

These agents are used to speed up the process of dough rising and also to expand the strength of dough.

 a. Oxidizing and reducing agents: Aging of flour occurs naturally when it is exposed to atmosphere. The oxidizing agents affect the sulfur-containing amino acids and aid to form disulfide bridges between the gluten molecules. The dough becomes stronger with the addition of these compounds. Examples of oxidizing agent include dehydroascorbic acid and potassium bromate, and they particularly oxidize the glutathione molecule. Potassium bromate acts directly and number of conversion steps are also less.Reducing agents make the flour weak by breaking the protein network. Benefits of the addition of reducing agents are reduction in mixing time, dough elasticity, proofing time, and improved machinability. Examples of reducing agent include cysteine and bisulfite.