Effects of Microwave Treatment on the Trypsin Inhibitor and Molecular Species of Triglycerides in Soybeans

Whole soybeans at different moistures (8.6, 24.3, and 49.7%) were heated by exposure to microwaves at frequency of 2,450 MHz. The trypsin inhibitor in soybeans at 24.3% moisture, soaked for 1 hr, was completely inactivated after treatment for 4 min, which was shorter than the heating period (6 min) needed for unsoaked soybeans. However, the trypsin inhibitor in soybeans at 49.7% moisture, soaked for 5 hr, was not completely inactivated even after heating for 12 min. The loss of molecular species of soybean triglycerides containing more than four double bonds in a triglyceride was less for soaked soybeans than for soybeans before soaking (8.6% moisture).