Effect of blanching and drying methods on beta-carotene, ascorbic acid and chlorophyll retention of leafy vegetables

Leaves of savoy beet (Beta vulgaris var bengalensis), amaranth (Amaranthus tricolor) and fenugreek (Trigonella foenum graecum) were subjected to different blanching and drying treatments to establish the retention of beta-carotene, ascorbic acid and chlorophyll. The vegetables were blanched at 95 +/- 3 degrees C in (i) water (ii) water followed by potassium metabisulphite (KMS) dip, (iii) salt solution, (iv) salt solution followed by KMS dip, and (v) mixture of sodium bicarbonate, magnesium oxide and KMS and dried in (a) sun, (b) shade, (c) solar drier, (d) cabinet drier, and (e) low temperature drier. Method (ii) was found most suitable for blanching and selected for subsequent drying and method (c) had least drastic effect on beta-carotene, ascorbic acid and chlorophyll content of the processed product.