Wheat structure and composition nn_053717.pptx

Nutritional composition and structure of wheat grain

1. Wheat structure and composition SUBMITTED TO: DR SHIKHA SINGH SUBMITTED BY: NADIA SAIFI MSc FOODS AND NUTRITION 1ST YEAR

2. Wheat is used principally for human consumption. It is converted into flour for the production of bread and other bakery products. It is used as ‘Chapatti’ in India. Wheat is being cultivated from prehistoric times(5000 BC) and is grown throughout the world. It is adaptable to different soils, climates and elevations. Wheat belongs to the genus Triticum and there are over 30,000 species and varieties. INTRODUCTION

3. STRUCTURE OF WHEAT

4. Structure of wheat WHEAT KERNEL: Wheat kernels are the seeds of the wheat plant, and they are the part of the plant that is milled into flour. Wheat kernels have three main parts: THE ENDOSPERM : While whole wheat flour contains all three parts of the kernel, white flour is milled from the endosperm. The endosperm makes up the bulk of the kernel. It is the whitest part, partly because it contains mostly starch- typically 70-75 percent starch. The starch is embedded in chunks of protein. Two important proteins in the endosperm of wheat kernels are the gluten-forming proteins, glutenin and gliadin.

5. THE GERM: It is the embryo of the wheat plant. Given the right conditions, the germ sprouts- germinates- and grows into a new plant. Wheat germ is high in protein, fat, B vitamins, Vitamin E, and minerals. These nutrients are important to the germ as it sprouts. THE BRAN: It is the protective outer covering of the wheat kernel. It is usually darker in color than the endosperm, except white wheat, which has a light bran.

6. COMPOSITION OF WHEAT

7. COMPOSITION OF WHEAT The values reported for Indian wheat are: Moisture 8.0-17.0 Starch 63-71 Sugars 2-3 Protein 8-15 Crude fibre 2-2.5 fat 1.5-2 and ash 1.5-2 percent The protein content of improved Indian wheat varieties has been reported to vary from 9.1 to 14.2 percent.

8. MINERALS: The mineral constituents present in Indian wheats are (mg/day): Calcium 41.0; Magnesium 138.0; Phosphorus 306.0; Iron 4.9. LIPIDS: The total lipid content of Indian wheat varies from about 0.97 to 2.28 per cent. The lipid content of endosperm (1-2 percent) is less than that of bran (5-6 percent) or germ (8-15 percent) but the proportion of compound lipids in the endosperm is much higher. VITAMINS: Whole wheat is a good source of thiamine and nicotinic acid, but is relatively poor in riboflavin. Other members of B- vitamins are present in small quantities. The distribution of some of the B- vitamins in the structural parts of the kernel of Indian wheat is given in the table in the next slide.

9. SRRUCTURAL PART Vitamin(Percent of total) Thiamine Niacin Riboflavin Pantothenic acid Pericarp, testa and hyaline 1 4 5 8 Aleurone 31 84 37 39 Endosperm 3 11.5 32 41 Scutellum 62.5 1 14 4 Embryo 2 1 12 3.5

10. FRACTION OF WHEAT ENDOSPERM GERM BRAN Starch 95.8 31.5 14.1 Sugar 1.5 36.4 7.6 Cellulose 0.3 16.8 35.2 Hemicellulose 2.4 15.3 43.1 CARBOHYDRATES : Among carbohydrates of wheat, particularly all of the starch is in the endosperm, while the soluble sugars are mostly found in the germ. The carbohydrates of bran are largely cellulose and hemicellulose. The distribution of carbohydrates in wheat fractions is presented in the table below:

11. REFERENCE Sharma A, Textbook of Food Science and Technology, (2017), 3 rd edition, (pg. 31), CBS Publishers & Distributers Pvt Ltd. Manay N S et al, Foods Facts And Principles, (2023), 5 th edition, (pg. 233-235), New Age International P Ltd