Cereal bars functionalised with tempeh: nutritional composition, isoflavone content and consumer acceptance

The aim of this study was to produce cereal bars (CB) added with tempeh flour (TF) and evaluate the nutritional composition, fatty acids profile, isoflavone content and sensory acceptance. Tempeh was produced from organic soya beans cotyledons fermented by Rhizophus oligosporus followed by freeze-drying and milling in order to obtain the TF. The addition of 10%, 15% and 20% TF to CB resulted in both protein and lipid content increase and a higher polyunsaturated/saturated fatty acids ratio. The content of isoflavone aglycones, the forms considered to have higher biological activity, was higher in TF than in soya bean, which was also reflected in the CB chemical composition. An acceptance test showed that CB added with TF (up to 15%) were sensory accepted. Overall results suggest that the addition of TF as an ingredient in cereal bars allows improving the chemical and functional characteristics of this type of ready-to-eat foods.