Improvement of the nutritional quality of lentil flours by infrared heating of seeds varying in size

The present study aimed to tackle research gaps regarding how infrared heating affected macro-and micro-nutrients of lentil flours from seeds varying in size. Infrared treatments reduced resistant starch contents of lentil flours from 26.1-33.6% to 6.0-17.8%, increased protein digestibility from 73.6-75.0% to 78.2-82.2%, and enhanced soluble dietary fiber contents from 6.1-7.8% to 7.4-10.3%. Infrared treatments did not alter the primary limiting amino acid of Greenstar and Imvincible lentil flours (tryptophan) but changed that of Maxim to methionine + cysteine at 150 C heating. Regarding micronutrients, the thermal modifications decreased the levels of heat-labile B vitamins, including B1 (thiamine), B3 (niacin), and B9 (mainly 5-methylterahydrofolate), consistent with reducing alpha-amylase activity to an undetectable level in all the three lentil flours. The novel findings from this research will be meaningful for the agri-food industry to utilize infrared processing as an effective and clean-label approach to improving the nutritional profiles of lentil and other flours.

Automated summary

The present study found that infrared treatments can reduce the resistant starch content and increase the protein digestibility and soluble dietary fiber content of lentil flours. However, it also decreases the levels of heat-labile B vitamins. These findings are important for the agri-food industry to improve the nutritional profiles of lentil and other flours using infrared processing.