Effect of fermentation on physico-chemical and biofunctional properties of concentrated cheese whey

This study investigated the proximate composition, chemical properties, and the effect of fermentation on physico-chemical and biofunctional properties of concentrated cheese whey fermented with probiotic culture Lactobacillus helveticus MTCC 5463. Cheese whey, a nutrient-rich by-product of cheese production, was concentrated to ~20% total solids and fermented at 37 °C for various durations. The optimal fermentation period was determined based on flavour acceptability, acidity, pH, and antioxidant potential assessed by ABTS, DPPH, and FRAP assays. Results showed that fermentation for 5 hours yielded the highest flavour score (8.17 on a 9-point hedonic scale) while significantly enhancing biofunctional property specifically the antioxidant activity as estimated by ABTS (1.36 mM trolox/mg protein), DPPH (0.29 mM trolox/mg protein), and FRAP (0.86 mM trolox/mg protein) assay. Although incubation up to 8 hours increased antioxidant activity but it simultaneously lowered the sensory acceptability due to excessive acidity and perception of bitterness. These findings suggest that controlled fermentation of concentrated cheese whey can improve its biofunctional properties, offering a promising approach for valorisation of dairy by-products.