Evaluation of physical and nutritional properties of extruded products based on brown rice and wild legumes mixtures

Abstract

The effects of the addition of wild legumes species (Lathyrus and Vicia genera) on physical and nutritional properties of extruded products based on brown rice were studied. Samples were obtained with a Brabender single screw extruder. Proximal composition of rice flour was studied both, before and after extrusion process. Physical characterization of the expanded products was performed by the measurement of density, expansion, solubility and specific mechanical energy consumption (SMEC). Chemical composition, amino acids content, protein digestibility, total polyphenol content and potential availability of iron and zinc were determined. Addition of legumes produces a decrease of expansion and an increase in solubility. With only 15% of legume replacement, a significant increase in protein content and quality, fiber, and mineral content was obtained. Protein digestibility ranged 82.5-85.3% and mineral availability 7.4-16.3% for iron and 10-14.6% for zinc. The performance of each mixture during extrusion and the physical properties of the extruded products were considered to be in the range of those expected for snack type products.