Preparation and characterization of emulsion gels from whole faba bean flour

Abstract

Faba bean protein has good functionalities, but it is little used in the food industry. This study identified a challenge from unfavourable starch gelation when utilizing faba bean for producing protein-based emulsion gel foods, and developed processing methods to overcome that. Two types of protein-based emulsion gel foods, namely yogurt and tofu analogue products, were prepared. The processing methods in this study involved steps of thermal pre-treatment of the beans, dehulling, milling, adding plant oil, homogenization, prevention of starch gelation, and inducing protein gelation. Two methods for preventing starch gelation were studied, namely starch removal and hydrolysis. The gel texture, water-holding capacity, and structural properties of the gel products were evaluated. Both starch-gelation prevention methods produced yogurt and tofu analogue products having typical emulsion gel properties. Hydrolysis of starch was favourable for producing the yogurt analogue, because the hydrolysate compounds improved the gel strength and viscosity. Moreover, it utilized the whole flour, meaning all the nutrients from the cotyledon were used and no side-stream was created. In contrast, starch removal was slightly better than hydrolysis for producing the tofu analogue, because the hydrolysate lowered the gel strength and water-holding capacity of the products. It is both possible and ecologically sustainable to utilize whole faba bean flour for making emulsion gel products.