Food Science and Processing

FOOD SCIENCE AND PROCESSING 3 (2+1)

Lesson 7 : Specific Cereals

Composition of Wheat

Carbohydrate: The main carbohydrate of flour is starch which forms about 66-68 per cent of flour. In addition, it contains sugars such as glucose, maltose and sucrose. Distribution of carbohydrate in wheat fraction is given in Table 2.2

Table 2.2: Percentage distribution of carbohydrate in wheat

Carbohydrate	Endosperm	Germ	Bran
Starch Sugar Cellulose Hemicellulose	95.8 1.5 0.3 2.4	31.1 36.4 16.8 15.3	14.1 76 35.2 43.1

Source: Shakuntala Manay N, 1987

Proportion of different proteins in wheat grain as percentage of total protein

Albumin	5-10
Globulin	5-10
Prolamine	40-50
Glutelin	40-50

Wheat proteins are rich in glutamic acid and low in tryptophan. The high concentration of amide is important in determining the characteristic of the gluten. The biological value of endosperm proteins is much less than that of the whole wheat protein.

Acarbose, an oligosaccharide present in wheat is a competitive inhibitor of sucrose and pancreatic analyse. It lowers the postprandial blood glucose rise.