Metabolic profile of Lactobacillus paracasei subsp. paracasei CRL 207 in solid state fermentation using commercial soybean meal

Solid state fermentation (SSF) using soybean meal and a lactic culture was used to obtain value-added products. The metabolites produced from a Lactobacillus paracasei subsp. paracasei CRL 207 during SSF were studied in 9 conditions of moisture and temperature. The greatest effect was best correlated with substrate moisture and it was shown that lactic fermentation was not accompanied by a pH decreases with certain conditions. Sugar intake, organic acid production, free amino acids profile, and isoflavones conversion were also measured. These factors helped in selecting the optimal conditions of 65% moisture and 37 °C to obtain a product with high concentrations of bioactive isoflavones (40.6 mg/50 g of wet product), organic acids (143 μmol/g) and free amino acids (31 μg/ml). Optimized fermented soy paste could be used as a base for development of new functional vegetable products and also, as a carrier of a potential probiotic microorganism as alternatives to dairy products.