Sprouting and hydrothermal treatments improve nutritional quality and consumer acceptability of biofortified common bean (Phaseolus vulgaris)

Nutritional quality and consumer acceptability of legumes is enhanced by application of sprouting and hydrothermal treatments. Nevertheless, with the increasing popularity of biofortification strategies for staple foods to counteract micronutrient deficiencies, little is known about the nutritional impact when these techniques are integrated. The purpose of this study was to ascertain the impact of combining sprouting and hydrothermal treatments: precooking, conventional cooking and pressure cooking (R-raw, RS-raw sprouted, SCC-sprouted and conventionally cooked, SPC-sprouted and pressure cooked, PCC-precooked and conventionally cooked, PPC-precooked and pressure cooked) on the nutritional quality and acceptability of biofortified common bean, nyota (Phaseolus vulgaris).

Results indicated significant increase in iron and zinc content by over 20% and 27% respectively, upon sprouting and hydrothermal treatments. Conversely, there was significant reduction in the phytate content by over 35%, tannin by up to 57%, oligosaccharides: stachyose by over 82%, verbascose by 91%, raffinose by 76%, and lipids from 2.56 ± 0.09(R) to 2.23 ± 0.27% (PPC). The phytate:iron molar ratio reduced significantly by up to 29%. On overall consumer acceptability, PPC was the most preferred at 6.03 ± 1.16 liking score.

Despite sprouting and hydrothermal treatments improving the nutritional quality of the bean, consumer education is required for increased acceptance and consumption of sprouted bean products.