Effect of microwave pre-treatment on protein extraction from de-oiled cottonseed meal and its functional and antioxidant properties

Abstract

Malnutrition and environmental sustainability are two major global concerns today for health and wellbeing of society as well as for economic development and prosperity of country. Cottonseed protein offers to be a promising candidate and sustainable source of protein but presence of deleterious polyphenolic compound gossypol impedes its application for food purpose. Effect of microwave radiations on toxic compound and properties of protein (concentrate and isolate) i.e. physicochemical, functional and anti-nutritional properties is investigated in present study. Cottonseed meal (CSM) used for protein extraction in present study contains 4.13% total gossypol and 0.81% free gossypol. Microwave pretreatment of meal prior to extraction process has shown substantial reduction of 50.17% in values of total gossypol. Further, both the untreated cottonseed meal and microwave pretreated meal (MW-CSM) were proceeded for protein extraction. Alkali-salt assisted extraction of protein from both the meals have resulted in reduction of free gossypol and total gossypol below permissible limits i.e., 0.45% and 1.20%, respectively. Optimized freeze-dried microwaved pretreated protein isolate contains 7.07% moisture, 92.79% crude protein, 0.05% free gossypol, 1.14% total gossypol and ash content of 1.47%. According to research, microwave treated cottonseed protein isolate (MW-CSPI) has shown notable modifications in its functional and anti-nutritional properties of protein.