Comparative Effects of Processing Methods on Hemagglutinating and Antitryptic Activities ofCanavalia ensiformisandCanavalia braziliensisSeeds

The effects of various processing methods on the hemagglutinating and antitryptic activities of the seeds of two species of the genus Canavalia, C. ensiformis and C. braziliensis, were investigated. Raw C. ensiformis and C. braziliensis contained 13 532 and 10 204 hemagglutinating units (HU), respectively, and also 1682 and 1662 trypsin inhibitor units (TIU) g - 1 of seed, respectively. Moist heat proved more effective than dry heat as a method of inactivating the two antinutritional factors in the seeds. Whereas 90 min of cooking at 96 °C was required to completely eliminate antitryptic activities of both species, 3 h of cooking was required to completely eliminate their hemagglutinating activities. Pressure cooking eliminated their antitryptic activities in 30 min and their hemagglutinating activities in 45 min. Soaking in water for even up to 96 h before cooking had no effect on hemagglutinating and antitryptic activities of C. braziliensis. Soaking in water for 72 h, however, completely eliminated the antitryptic activity of C. ensiformis in 30 min of cooking and the hemagglutinating activity in 60 min of cooking. Breaking the seeds before cooking proved to be most effective, resulting in complete elimination of antitryptic and hemagglutinating activities of both species in 30 and 60 min of cooking, respectively, and is therefore most highly recommended. Keywords: Canavalia ensiformis; Canavalia braziliensis; antitryptic/hemagglutinating activities; processing methods