Effect of infrared heating on the properties of legume seeds

Five legume seeds (kidney beans, green peas, black beans, lentil and pinto beans) were heated by infrared to a surface temperature of 140 degreesC. The changes in chemical composition, physical, mechanical and functional properties of the processed seeds were measured and compared to those of the raw seeds. Significant changes in the properties of the seeds in terms of increased volume, lower rupture point and toughness, higher water uptake and higher leaching losses (when the seeds were soaked in water) were obtained. The changes in the physical and mechanical properties were attributed to possible cracking of the seed. Even though trypsin inhibitor activity was reduced, infrared heating did not significantly affect the starch and protein components of the seeds. The functional characteristics of flour from the infrared-heated seeds were superior to those of flour from untreated seeds.