Food Chemistry Archives - Page 2 of 2

Jun 18

Modification of Fats and Oil: Hydrogenation

Hydrogenation of vegetable oil refers to conversion of unsaturated liquid oil into saturated or partially saturated plastic fat by catalytic addition of hydrogen. Most widely used catalyst is nickel. The main purpose of hydrogenation of vegetable oil is

To modify oil for application in wide range of food uses such as production of margarine, deep frying oil, shortening in biscuit etc.
To extend shelf life of fat by improving oxidative stability by reducing unsaturation. Unsaturated fats and oils are very susceptible to spoilage called rancidity.

For successful hydrogenation, crude oil impurities like phosphorous and sulfur compounds, free fatty acids, and residual soap need to be removed before proceeding for hydrogenation. These impurities have poisoning effect on catalyst and reduce its activity. Canola and rapeseed oil are particularly notorious for high level of natural sulfur which can cause problem in hydrogenation. Read more

Jun 16

Modification of Fats and oil: Fractionation

Different functionalities (nutritional and physical) require specific compositions that are usually not found in a single natural fat or oil. For this reason, fats and oil are often modified in order to achieve these desired compositions and thus physical and nutritional properties. For example; melting behavior, solid fat content are important factors in formulation of shortening and margarine while decreasing poly unsaturated fatty acids (PUFAS) to increase oxidative stability is important in frying oil. Following are the commonly used methods used to modify fats and oil Read more

Jun 15

Protein Quality, Sources and Dificiency

Protein quality: It is the digestibility and quantity of essential amino acids for providing the protein in correct ratio for human consumption. There are various methods that rank quality of different types of protein. Some of the popular methods are Protein digestibility corrected amino acid score (PDCAAS) and Digestible indispensable amino acid score (DIAAS). Read more

Jun 14

Protein and Amino-Acids

Protein are complex nitrogenous organic compounds which are essential for physical and mental growth and development of body. They are defined as long chain polymer of α – amino acids bounded by peptide linkage. Therefore, protein are polypeptides of high molecular weight ranging from 5000 to many millions.