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The composition of bioactives including polysaccharide yield and resistant starch (RS) content of 4 raw and cooked bean ( Phaseolus vulgaris L.) cultivars was evaluated. Polysaccharide was fermented in vitro by incubation with human gut flora under anaerobic conditions and short-chain fatty acids (SCFAs) production was compared at 6, 12, and 24 h by gas chromatography. Polysaccharide and soluble fiber contents increased upon cooking with stachyose as the major oligosaccharide. Cooked bean of cultivar Bayo Madero had the highest yield of polysaccharides (55%) and resistant starch (37%), followed by those of Negro 8025 (48% and 32%, respectively). Acetate was the most abundant SCFAs formed in all bean varieties. The concentration of SCFAs was cultivar-dependent; Bayo Madero and Negro 8025 displayed the highest concentration of butyrate (15 mmol/L), while Azufrado Higuera had the lowest and highest concentrations of acetate (39 mmol/L) and propionate (14 mmol/L), respectively. The results suggest that the common bean is an excellent source of polysaccharides that can be fermented in the colon and produce SCFAs, compounds previously reported to exert health benefits. [ABSTRACT FROM AUTHOR]

BSTRACT: The effects of calcium hydroxide and screw speed on expansion, pasting, crystallinity, torque, water absorption, and solubility indices upon extruded blue maize meal products were studied, using a central composite experimental design. All the characteristics measured presented a significant quadratic regression model, indicating relationship between the responses and extrusion conditions. It was found that the expansion, crystallinity, torque, water absorption, and solubility indices decreased and the Rapid Viscosity Analyzer's (RVA) pasting characteristics increased with the increase of calcium hydroxide concentrations. The Pearson correlation indicated that the responses presented strong correlation (r > 0.7, p < 0.01) between them. Extruded products with physical appearance and expansion similar to the control were found at concentrations lower than 0.1% of calcium hydroxide. [ABSTRACT FROM AUTHOR]