Formulation of plant-based yoghurt from soybean and quinoa and evaluation of physicochemical, rheological, sensory and functional properties

The aim of this study was to develop a novel plant-based yoghurt with high sensory acceptance and nutrition value. Soybean and quinoa were used as the substrates, and all formulations with different substrate ratios were inoculated with lactic acid bacteria (LAB). Fermentation modified the proximate composition, and a higher content of soybean accentuated the growth of LAB. Formulated yoghurts presented a weak post-acidification, and the viability of LAB was higher than 10 6−7 CFU/g during a 21 days storage. Quinoa addition significantly improved the water holding capacity (WHC) and decreased the yellowness, and an increase of lightness and a decrease of WHC occurred during the storage. Compared with the plain substrate yoghurt, mixed formulation had no significant impact on textual parameters, whereas increased the liking scores in sensory evaluation. Furthermore, fermentation improved the total phenolic content (TPC), which showed a dose-dependent relationship between soybean content. Results obtained from DPPH, ABTS, hydroxyl radical scavenging assay, FRAP assay, and α-amylase, α-glucosidase and pancreatic lipase inhibition assay showed that fermentation enhanced the antioxidant capacities and digestive enzyme inhibitory activities. TPC increase and phenolic biotransformation may explain the enhancement of the nutritive values. Based on the sensory and function evaluation, the ratio of quinoa against soybean at 8:2 and 2:8 presented the best formulations. • Quinoa and soybean were used to prepare plant-based yoghurt. • Mixed formulation improved fermentation and storage properties of yoghurt. • Mixed substrates enhanced textual and rheological properties of yoghurt. • Fermentation enhanced the antioxidant and digestive properties. • The ratio of quinoa against soybean at 8:2 and 2:8 presented the best formulations.