Nutritive value

FOOD SCIENCE AND PROCESSING 3 (2+1)
Lesson 14 : Vegetables

Nutritive value

  1. Nutritive value of green-leafy vegetables: The crispness of greens depends on the water in the cells. Partial dehydration of cells results in a change from crisp to a limp leaf. The leaves in consequences are low in carbohydrates and energy but they are good sources of β- carotene, calcium, riboflavin, folic acid, ascorbic acid, iron and vitamin K.
    • Generally green leafy vegetables are good sources of vitamins and minerals. They are excellent in carotenes which are converted to vitamin A. Among all the greens colocasia leaves contain highest amount of carotene and cabbage has the least. The greener the leaves the higher the carotenes. β –carotenes are also good antioxidants.
    • Greens are good sources of B-vitamins particularly riboflavin and folic acid. Drying and withering reduce B-vitamins.
    • Green-leafy vegetables also contain vitamin C and can be used as substitute for fruits if needed. Agathi, drumstick leaves and coriander leaves contribute to vitamin C. The practice of using coriander as garnishing agent is good as heating results in some loss of vitamin C.
    • Green leafy vegetables are also rich in iron. The leaves normally discarded like cauliflower leaves and beetroot leaves are excellent sources of iron. Mint and mayalu (red bacchali) are good in iron content.
    • Agathi, colocasia leaves, drumstick leaves and fenugreek leaves contribute calcium in our diet. The availability of calcium and iron to the body is limited as greens also contain oxalic acid.
    • Greens generally are high in moisture and easily withered and need to preserve properly.
    • Greens are not good sources of protein, fat and carbohydrate and hence they do not contribute to the energy value of food.
    • Greens are good sources of fiber which help in preventing degenerative diseases.
    • Of all the green leafy vegetables agathi is the most nutritious one.

  2. Nutritive value of roots and tubers
    • Roots and tubers give more calories compared to green-leafy vegetables because they contain more starches.
    • Carrots contain high amount of carotene though this amount is lower when compared to the content present in green leafy vegetables.
    • Roots and tubers are fairly good source of vitamin C.
    • They are poor source of calcium, iron and B- vitamins.
    • They are poor source of protein.

  3. Nutritive value of other vegetables
    • They contain high amount of moisture and hence they are highly perishable.
    • They are generally poor in all nutrients.
    • They are fairly good source of vitamin C.
    • They contribute to the fibre content of the diet.
    • Plantain green contains high amount of iron.
    • Capsicum contains vitamin C.
    • Small bitter gourd is more nutritious than the ordinary one.

  4. Other chemical compounds occurring in vegetables: Vegetables contain several groups of chemical compounds such as
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Last modified: Saturday, 10 December 2011, 9:35 AM