Effect of lactic adjunct cultures on conjugated linoleic acid (CLA) concentration of yogurt drink

Abstract

The effect of adjunct culture addition on conjugated linoleic acid contents of yogurt drink was determined. Yogurt drink production was carried out under industrial conditions. Yogurt drink samples produced by conventional cultures (Streptococcus thermopiles and Lactobacillus delbrueckii subsp. bulgaricus) were used as a control group while Lactobacillus reuteri ATCC 55739 or Lactococcus lactis subsp. lactis IO-1 were used as adjunct cultures, which were added to yogurt drink samples containing conventional cultures. Sunflower oil (as a substrate for linoleic acid) of 0.1g/ L (in final products) was supplemented to each yogurt drink group to accelerate CLA production. Chemical, microbiological and sensory properties of yogurt drink samples were determined during a storage period of 10 days at 4°C. In general, the use of Lactobacillus reuteri ATCC 55739 as an adjunct culture increased CLA concentration in yogurt drink (p<0.01). The incorporation of adjunct culture in yogurt drink product had no negative effect on sensory properties of samples.