Characterization of Fava Bean Hydrolysates for Future Use in Protein Enriched Beverages

Abstract

Fava beans (Vicia faba), a member of the Fabaceae family, are a nutrient-dense legume with growing potential as an ingredient in plant-based, non-dairy beverages. Their high protein content and balanced amino acid profile make them a promising alternative to whey protein, which is non-vegan and a common allergen. This study aimed to determine how partial hydrolysis of fava bean protein isolate using the food-grade enzyme Alcalase affects its solubility in acidic beverages, and to identify key volatile compounds contributing to flavor. Protein hydrolysis was carried out at 50 °C for 40 minutes, with samples collected at 0, 20, and 40 minutes. Hydrolysis was monitored using sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE), which revealed extensive protein breakdown within the first 20 minutes, with molecular weights shifting primarily into the 10–20 kDa range. Solubility testing across pH values showed that the hydrolyzed protein retained significantly higher solubility in acidic conditions (pH 3–5) compared to the non-hydrolyzed control. Volatile and aroma-active compounds were characterized using solid-phase microextraction gas chromatography–mass spectrometry, and olfactometry (SPME-GCMS, SPME-GCO) was used to identify key volatile compounds, including aldehydes (hexanal, nonanal), alcohols (1-octen-3-ol), and furans (2-pentylfuran). Hexanal was present in all samples, while 2-pentylfuran produced the most prominent peak, with green bean, nutty, and vegetable-like flavor