Chemical and non-nutritional modification of faba bean (Vicia faba) due to the effect of roasting and boiling

Mexico has various Faba bean (Vicia faba) seeds, differentiated by agronomic and chemical properties. The present work evaluates the effect of thermal treatment (roasting and boiling) on chemical and non-nutritional components of three varieties of faba bean (Vicia faba). Three faba bean Mexican varieties were utilized, of late, intermediate, and early maturity, under thermal treatments of roasting (120°C/10 min) and boiling (120°C/20 min, 1.0546 kgf/cm2). Results demosntrated that the treatments have different results: while the content of fiber and ashes increases with both methods, the proteins, ether extract, and carbohydrates remained constant with the samples boiled. In contrast, only the concentration of ethereal extract is affected with toasted. Similarly, digestibility increased from 2 to 6% after both treatments. Furthermore, trypsin inhibitors decreased between 79 and 89% in the three varieties with roasting, while in boiling they were eliminated. Phytic acid decreased 40-33% in the HTA and HTP varieties regardless of the thermal treatment; for the HPA variety, it was possible to reduce up to 31% in roasting and 20% in boiling Total and condensed phenolics, vicin and convincin, decreased to 23 and 33% in heat-treated samples, mainly when boiled L-DOPA was only present in two raw species (HPA and HTA), and it was eliminated with both treatments. Thermal treatments improved the biological quality of proteins in faba bean seeds by removing or reducing the concentration of non-nutritional compounds and increasing the digestibility of nutrients.