What is rancidity?
Rancidity is the chemical decomposition of fats, oils and other lipids. There are three basic types of rancidity. Hydrolytic rancidity occurs when water splits fatty acid chains away from the glycerol backbone in glycerides. Oxidative rancidity occurs when the double bonds of an unsaturated fatty acid react chemically with oxygen. Microbial rancidity refers to a process in which microorganisms such as bacteria use their enzymes, including lipases, to break down chemical structures in the fat. In each case, these chemical reactions result in undesirable odors and flavors.
Name two anti oxidants which are usually added to fat and oil containing foods to prevent rancidity?
what is rancidity? Rancidity describes an oil which is no longer fresh. Cooking oils should be stored in dark cabinets and dark glass bottles if possible. Exposure to constant re-warming, light, and heat cause the bonds in oils to breakdown and this creates free radicals which are harmful dietary products. A helpful phrase to remember is: "when in doubt, throw it out." Also, an oil smells different when it is rancid, but will not necessarily…
The chemical reactions that take place in food decay are: Fermentation - changes taking place by the actions of enzymes, specifically ferments such as molds, bacteria, and yeast. Microbial rancidity - deteriorative changes in fats over time. Hydrolytic rancidity - hydrolysis of fatty acids and water Oxidative rancidity - oxidation of acylglycerols which occurs in air; without the presence of enzymes, is called autoxidation. For more information, visit the Related Link.
Keep water and oxygen out. Both of these contribute to rancidity reactions and microbial growth. Cereals typically have about 3% moisture, though most of this water is not available for any chemistry to occur. Even so, water within cereal will ultimately lead to rancidity. Sealing your cereal and freezing it is probably your best bet if you want to really make it last.