DEVELOPMENT AND PRODUCTION OF A PROBIOTIC INOCULUM USING WHEY PERMEATED BY FERMENTATION

LÓPEZ GIRALDO, L.J.; SOTO, L.P.; TORRES TÉLLEZ, L.F.; BARRERA LEMUS, L.P.; FRIZZO, L.S.

Medellín

Conferencia; PROCESA; 2019

Consejo Profesional de Ingeniería Química de Colombia

The aims of this work were to determine an optimal growth medium for lactic acid bacterium using whey permeate, the operation mode (batch vs fed-batch) that drives to obtain better biomass yields and the type of lioprotector that aids to stabilize the biomass obtained.Initially, different media were prepared with micronutrients, macronutrients and salts to identify compounds that permit increase biomass production, finding that the growth medium per liter contained: sorbitan monolaurate 1 [ml], dipotassium phosphate 10 [g], sodium acetate (tryhidrate) 10 [g], manganese sulfate monohydrate 0.02 [g], then the concentration of carbon and nitrogen source were varied using an approximation of one factor change at a time and evaluating for each change the biomass yield, finding that 20 [g/l] of whey permeate and 20 [g/l] yeast extract led to a yield of 0.413(g de Biomass)/(g de Substrate).Then, a batch vs fed-batch mode operation were compared, four liters of medium was used for each fermentation mode, as a result, the biomass productivity of a fed-batch process was 1.35 times more than a batch process.Finally, three lyoprotectants were tested: maltodextrin, whey permeate and dextrose, these have been used in previous studies as protective agent for probiotic lactic acid bacteria (Strasser et al. 2009, Reddy et al. 2009), each lyoprotectant was mixed with biomass and subsequently lyophilization process was performed and biomass pellet + lyoprotectant were stored at room temperature for one month, count method in plates was made every week to determine the bacterial concentration, finding that the whey permeate was the best conservative biomass with 4539 ± 0368 log CFU / ml.Related to the best concentration of carbon and nitrogen source, the results showed that biomass yield with 20 [g/l] whey permeate and 20 [g/l] yeast extract is 1.33 times less than reported by Malek et al. 2010 but using glucose as carbon source. In connection with the operation mode, biomass productivity in fed-batch operation was 0.606 g/(l×h) compared to 0.450 g/(l×h) in batch operation. At last, the whey permeate was the best lyoprotectant.