Analytical Methods
The samples were centrifuged at 10,000g at 15˚C for 20 min. The supernatants were analyzed for
concentration of lactic acid [6], starch [7], chemical oxygen demand (COD) [8] and total kjeldahl nitrogen (TKN) [8].
The biomass concentration was determined by drying the cells at 80°C until a constant weight was
obtained.
Then, the dried cells were weighed.
The viable LAB were enumerated by the spread plate technique with the use of MRS agar.
DO was measured using a DO meter (YSI 200, YSI Inc., USA).