Healthy novel gluten-free formulations based on beans, carob fruit and rice: Extrusion effect on organic acids, tocopherols, phenolic compounds and bioactivity

Abstract

Rice and legumes have great potential in the development of novel gluten-free snacks that are healthier than traditional snacks. Novel gluten-free extruded foods (composed of rice: 50-80%, beans: 20-40% and carob: 5-10%) were analysed and the extrusion effects regarding organic acids, tocopherols, phenolic compounds and bioactive properties were evaluated. The total concentration of organic acids was not significantly affected by extrusion, while tocopherols showed a significant reduction. Extrusion did not produce an increase of the total phenolic content. For the bioactivity assays, commercial extruded rice, carob and most of the extruded samples showed anti-proliferative activity, which was higher than in the non-extruded samples, while for the anti-inflammatory activity, the extrusion process did not show a significant effect. Regarding the antimicrobial activity, low potential was observed with extruded and non-extruded samples showing high values of MIC and MBC as the microorganisms tested were multi-resistant isolated clinical strains.

Keywords: Bean/rice/carob fruit; Bioactivity; Chemical composition; Extrusion; Phenolic profile.