Formation of conjugated linoleic acid by a Lactobacillus plantarum strain isolated from an artisanal cheese: evaluation in miniature cheeses

Abstract

Among 129 lactic acid bacteria previously isolated from raw-milk starter-free cheeses manufactured in Galicia (NW Spain), two strains of Lactobacillus plantarum were definitely recognised as producers of conjugated linoleic acid (CLA). Gas chromatography analysis identified cis-9, trans-11 C18:2 as the predominant CLA isomer formed in MRS broth supplemented with linoleic acid. A centrifugation-based model for the manufacture of miniature cheeses was used to evaluate the formation of CLA by Lb. plantarum L200, the highest producer of CLA in MRS broth. The miniature cheeses made with the addition of the L200 strain showed significantly (P < 0.05) higher contents of cis-9, trans-11 CLA than those of the control cheeses (1.09 versus 0.69 percentage of total fatty acids, respectively). These results suggest that Lb. plantarum L200 strain could be used as an adjunct culture to slightly increase the concentrations of CLA in short-ripened cows' milk cheeses.