PRODUCTION of FREEZE DRIED PROTEIN and Lactobacillus Casei PROBIOTIC BIOMASS FROM MILK WHEY

In this communication, we document the technical feasibility of elaboration of two added value products from milk whey (a) freeze-dried protein and (b) freeze-dried probiotic biomass of Lactobacillus casei. Results from milk whey ultrafiltration experiments are presented, from which high protein/lactose ratio protein is recovered. In its lyophilized form, this protein presents superior solubility characteristics with respect to analogous commercial products. The ultrafiltration permeate was utilized as growth culture medium for the probiotic microorganism L. casei. Results from batch and fed-batch fermentation experiments are reported. The growth kinetics of L. casei in de-proteinized milk whey is analyzed. From batch experiments, a kinetic characterization is conducted. A strong inhibition of biomass growth by lactic acid production is observed. Fed-batch strategies resulted in higher average productivities, lower residual substrate concentrations, and higher product viable counts than batch strategies.