Question

Name the type of chemical reaction responsible for rancidity and define it

Answer 1

Answer:

The Maillard reaction is a chemical reaction between amino acid and reducing sugars that gives browned food its distinctive flavor ... The reaction is the basis for many of the flavoring industry recipes.

At high temperatures, a probable carcinogen called acrylamide can form

Answer 2

Rancidity: Rancidity can be defined as the chemical decomposition of fats and oils due to hydrolysis or auto-oxidation or microbial activity, producing aldehydes, hydroxyl acids, keta acids, and other compounds. This causes a considerable damage to the natural structure of fats and oils, producing undesirable odors, flavors and discoloration  in the food containing them; making them unfit for consumption.

For Example: When butter is kept open for a long time, then its smell and taste gets changed (due to the presence of butyric acid (a four-carbon acid).

Factors responsible for causing rancidity are light, oxygen, trace elements such as iron and zinc, salt, water, bacteria, and molds etc.

Types of chemical reactions responsible for causing rancidity:

(i) Oxidation Reaction:  Oxidation is said to have occurred when a substance reacts with oxygen in the air forming oxides. It causes the formation of peroxide at the double bonds (C=C) of fat molecules with subsequent breakdown of these peroxides to form aldehydes, ketones and acids of lower molecular weight. This results in off-flavor, off-odour and sometimes change in colour.

(ii) Hydrolysis: Hydrolysis can be defined as the breaking down of a chemical compound into two or more simpler compounds by reacting with water. It decomposes a lipid into its component fatty acids and glycerol.

               C-O-CO-R + H2O →  C-O-H + HO-CO-R