Whey permeate as a medium for growth and spray drying of Lactobacillus plantarum CIDCA 83114

FLORENCIA BRUNO; MARINA A. GOLOWCZYC; JESSICA MINNAARD; AYELEN A. HUGO

Congreso; II PreProSim 2015; 2015

Objective: The whey permeate is a lactose-rich waste from the cheese industry and could be used as an economic growth substrate for probiotic bacteria. Spray drying has proven to be useful to obtain dehydrated probiotic in a viable state. Thus, the aim of this work was to evaluate the suitability of using whey permeates as a culture broth for probiotic lactobacilli and a as carrier to obtain viable dehydrated bacteria using spray drying.Methods: probiotic Lactobacillus plantarum CIDCA 83114 was grown at different concentrations of whey permeate. Growth kinetics, acid tolerance (incubation in PBS at pH 2.5) and bile tolerance (incubation with 0.5% of ox bile) were measured. Also microorganisms were dried directly from the growth medium (whey permeate) in a laboratory-scale spray-dryer (model B290 Büchi mini spray-dryer) at a constant air inlet temperature of 170 °C and an outlet temperature of 75?80 °C, and survival rate was quantified. Results were compared with bacteria grown in MRS broth.Results: L plantarum CIDCA 83114 exhibited similar growth velocity in whey permeate 5% and 20% with a generation time (g) of 6.3 h. It reached a maximum concentration of 1 x108 CFU/ml after 16 h of incubation at 37 °C in both formulations. Lactobacillus growth was optimal in MRS broth with a g of 0.85 h and a maximum crop of 2 x109 CFU/ml.Strain CIDCA 83114 showed a low tolerance to acid conditions and bile presence when it was grown in MRS broth with a decrease of 5 log CFU/ml in cell viability. Interestingly the reduction of viable counts was only 1 log CFU/ml when the strain was grown in whey permeate.This microorganism displayed a high resistance to spray drying process with a viability decrease of only 10 %. There was no difference in bacteria survival among the strain grown in MRS and the strain grown in whey permeate. Conclusions: Whey permeate is a suitable medium for the growth of L. plantarum CIDCA 83114. The growth in this medium produced a significant increase in resistance to passage through the GI tract which is an important requirement in the selection of probiotic strains. Also, spray-drying is a highly efficient process for dehydration of this strain and the use of this process is highly recommended for obtaining dried probiotic strains that could be incorporated into functional foods