Effect of pretreatment by supercritical fluids on antioxidant activity of protein hydrolyzate from quinoa ( Willd.).

The effect of two pretreatments on the antioxidant activity was evaluated in quinoa protein hydrolysate, using supercritical CO extraction and ethanol as cosolvent, this type of pretreatment was compared to a conventional petroleum ether extraction method without recovery of bioactive compounds. The extractions were carried out at a temperature of 55°C and a pressure of 23 MPa using ethanol (7-8 g quinoa/100 ml); the CO mass flow was 35 g/min, the extraction time was 240 min and the particle size was 500 µm, enzyme COROLASE 7089 was applied for enzymatic hydrolysis, finally ABTS test assessed antioxidant activity. A significant effect was found on the degree of hydrolysis (23.