Impact of fermentation of okara on physicochemical, techno-functional, and sensory properties of meat analogues

As a result of agri-food production, large quantities of organic waste are produced in the form of press cakes (by-products of plant-based drink production), and a huge quantity of these by-products is generally discarded, leading to environmental problems. This research aims to evaluate the effects of fermentation of Ultrasound (US) treated okara (soy press cakes) on protein oxidation level, techno-functional, texture and sensory properties of the meat analogues. Okara samples were fermented by applying L. plantarum P1 and L. acidophilus 308 strains. The meat analogues were produced by adding 3% and 6% fermented okara to the matrices. Fermented okara and matrices were maturated at temperatures 4 °C or 18 °C, separately. The effects of fermentation conditions, the amount of okara, and the dough maturation temperature, as well as the interaction effect on protein oxidation level, techno-functional, sensory, and textural properties of meat analogues were analysed. The results indicated that okara is a suitable source of fibre, plant-based proteins, and essential amino acids, and demonstrated the potential of the application of fermentation to improve water-holding capacity and sensory properties of meat analogues, as well as to reduce hardness and protein oxidation levels. The study recommended that the optimum condition for producing meat analogues was the application of 6% okara in the matrices fermented by L. plantarum P1, when the matrices and okara are maturated at 4 °C for 2 h. The research finally concluded that the use of fermentation process on US-treated okara makes it a suitable component of meat analogues.