Effect of milk enriched with conjugated linoleic acid and digested in a simulator (TIM-1) on the viability of probiotic bacteria

The impact of fatty acids on the growth of lactobacilli and bifidobacteria was studied to gain insight into the beneficial effects of conjugated linoleic acid (CLA) and probiotics. Milk was enriched with CLA by adding 4% safflower oil to the cow diet, by emulsifying synthetic CLA as free fatty acids, or by emulsifying CLA as triacylglycerol, then adjusted to 1.0% or 3.25% fat and digested in a gastro-intestinal simulator. The residual fatty acid contents of milk samples containing initial fat contents of 1.0% and 3.25% were significantly different after 6h digestion. Milk enriched with synthetic CLA and adjusted to 1.0% fat appeared to provide a digest that allowed growth of both Lactobacillus rhamnosus R0011 and Lb. rhamnosus LGG; adjustment to 3.25% fat decreased viable LGG slightly. Digestion of milk containing 3.25% fat appeared to yield a residual fatty acid mixture that may be slightly bactericidal or simply bacteriostatic. © 2014 Elsevier Ltd.