Lactic acid fermentation by Lactobacillus fermentum PL1 using a different volume of triticale stillage

Abstract

Triticale stillage is a by-product of the bioethanol fermentation. It is used as the addition to feed and needs the protection from spoiling and pathogens. Lactic acid bacteria can be used for it, and triticale stillage is then used as a medium for their growth and the lactic acid production. The aim of this work was to see if there is a possibility for scale up of the lactic acid fermentation process (by increasing 10 times medium volume), when an inoculum is Lactobacillus fermentum PL-1. Titrable acidity and pH were measured during the lactic acid fermentation. Utilization of carbohydrates and the concentrations of D- and L- lactic acid were determined by enzymatic kits. Viability of the lactic acid bacteria cell was done by pour a plate method. There was no difference in pH value during the process (medium volume changed from 25 to 250 mL), while titrable acidity was significantly lower. The L-lactic acid yield was also smaller, but not significantly. Utilization of carbohydrates was complete in both cases, and viability was better in the samples with the usual experimental design. Given results indicate that the volume of the fermentation medium can be increased on a pilot level, for example.