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

Food Chem. 2022 Dec 1:396:133649. doi: 10.1016/j.foodchem.2022.133649. Epub 2022 Jul 8.

Abstract

The present study aimed to tackle research gaps regarding how infrared heating affected macro- and micronutrients 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 α-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.

Keywords: Dietary fiber profile; In vitro protein digestibility and quality; In vitro starch digestibility; Infrared heating; Lentil flour; Seed size; Vitamin B complex.

MeSH terms

  • Flour / analysis
  • Heating
  • Lens Plant* / chemistry
  • Micronutrients / analysis
  • Nutritive Value
  • Seeds / chemistry
  • Starch / metabolism

Substances

  • Micronutrients
  • Starch