Optimisation of lactic acid fermentation of York cabbage for the development of potential probiotic products

In this study, York cabbage was used as the sole substrate for the lactic acid (LA) fermentation with Lactobacillus plantarum. York cabbage was blanched at 95°C for 12min to inactivate surface microflora prior to fermentation. To achieve an optimal fermentation condition that would result in higher release of phytochemicals and antioxidant (AO) capacity in the broth, Box-Behnken design integrating a desirability approach was used. A second-order polynomial equation was developed, indicating the effect of solute/liquid ratio, agitation rate and fermentation time on desired parameters. The optimised factors were used for fermenting York cabbage to obtain maximum bacterial growth, LA, polyphenols and AO capacity. There was ≈5logcfumL ^-1 increment in bacterial growth after fermentation, whereas LA production reached up to 4.97mgmL ^-1. Results showed that fermentation retains 95-98% and 90-95% of TPC and AO capacity, respectively. During refrigerated storage (4°C), the cell numbers, bioactive components and acidity were maintained till 15-day storage.