FOOD 2400 Chapter Notes - Chapter 4: Short-Chain Fatty Acid, Lipid Peroxidation, Autoxidation

• School: University of Guelph
• Department: Food Science
• Course: FOOD 2400
• Professor: Yoshi Mine

Document Summary

Unit 4: lipids- reactions in lipids, lipolysis & oxidation. Rancidity: the o - avours and o -odours associated with lipid deterioration: can be either hydrolytic or oxidative in nature, autoxidation = oxidative rancidity, lipolysis = hydrolytic rancidity. Oxidative rancidity: an undesirable reaction which a ects fats, oils, and fatty parts of foods caused by reactions involving oxygen. Oils from oil seeds (in contrast to animal fats) may have undergone substantial hydrolysis by the time they are harvested, giving rise to signi cant amount of free fatty acids. Neutralization with alkali (e. g. naoh) is thus required for most vegetable oils after they are extracted: the release of short chain fatty acids by hydrolysis is responsible for the development of rancid avours in raw milk. Certain cheese avours are produced by deliberate addition of microbial and milk lipase. Controlled and selective lipolysis is also used in the manufacture of other foods such as yogurt and bread.