Effect of a Bangladeshi home-cooking procedure on the amino acid content,trypsin inhibitor activity and in vitro digestibility of some legume seeds

Raw and cooked samples of cultivars ofLens esculenta (Lentils),Pisum sativum (peas),Phaseolus vulgaris (beans),Phaseolus aureus (navy beans)Cicer arietnum (gram), andLathyrus sativus (dhal) as well as precooked commercial products were analysed for amino acids, trypsin inhibitor activity and in vitro protein digestibility. Of the fifteen samples used in the study one lentil sample, one pea sample, two gram samples and one sample of khesari dhal were from Bangladesh, one gram sample was from Sri Lanka. The other samples were obtained either in shops in Norway or from an industrial firm. The latter were also obtained precooked and dried. The two samples obtained in shops were used with hull and dehulled.Neither cooking by a Bangladeshi household procedure nor industrial precooking and drying had any effect on the amino acid contents of the samples.Cooking and precooking reduced the trypsin inhibitor activity of the raw samples more when the original activity was high then when it was low. The inhibitor activity was similar between samples after cooking.Cooking and precooking and drying increased the in vitro protein digestibility in all samples except in the lentils in which the digestibility was reduced.In the raw samples protein digestibility was negatively correlated with the trypsin inhibitor activity.