PREPARATION OF PROTEIN ISOLATE AND HYDROLYSATE FROM DEFATTED SUNFLOWER SEEDS AND STUDYING THEIR CHEMICAL COMPOSITION

Abstract

This study aimed to prepare protein isolate and hydrolysate (enzymic method) from defatted sunflower seeds and studying the chemical composition of both product, Sunflower seeds(Helianthus annuus L)were defatted ''using organic hexan''and used to prepare the sunflower meal. The protein content extracted and isolated using alkali extraction, protein precipitated at isoelectric point. The obtained isolate treated with Flavourzyme (300 unit) and the hydrolysis carried out at 55ºC for 4h. till the degree of hydrolysis reached to 21.6% . The final products dried under vacuum. The results showed that the chemical composition of sunflower meal were 50.89%, 4.9%, 4.53%, 4.32%, 27.14% and 1.61% for protein, fat, fiber, ash, moisture, soluble sugars and total polyphenols respectively, while for protein isolate those values were 85.82%, 0.76%, 5.30%, 1.16%, 3.62%, 2.18% and 0.70% respectively. The protein hydrolysate content of protein was higher (91.5%) than that for protein isolate, whereas the other component values were lower.