Investigations on the trypsin inhibitor,urease and cooking behaviour of soybean Glycine max Merr.

Eleven varieties of soybeans were analysed for their trypsin inhibitor activity (TIA), urease activity and cooking behaviour. The TIA ranged between 8·1 and 38·5 trypsin units inhibited per mg meal. In general, black soybeans contain higher trypsin inhibitor activities than yellow varieties. There was no appreciable variation in urease activity whose values ranged between 1·93 and 2·12 pH units. Considerable variability was evident in cooking behaviour of soybeans. The cooking period ranged between 140 min and 318 min. Thus the present study suggests the possibility of lowering trypsin inhibitor activity and cooking periods by further selection and breeding programmes of soybean cultivars.