Screening of some potentially probiotic lactic acid bacteria for their ability to synthesis conjugated linoleic acid

In this study the physicochemical, microbiological, and fatty acid compositions together with the specific esterase activities of semi-hard goat cheeses made from native strains as starter and adjunct cultures were evaluated and compared against those of manufactured using commercial culture cheeses. The physicochemical composition was similar among cheeses, while the lactic acid bacteria were the predominant microbiota in all samples. The highest specific esterase activities were detected in cheeses with native strains. The fatty acid profile was significantly affected by native strains during the ripening time (60 days) since the conjugated linoleic acid (CLA) level increased from 0.60 to 1.03 g 100 g-1 of fatty acids, whereas cheeses with commercial starter showed a CLA content of about 0.60 g of fatty acids. In cheeses with native strains, it was detected the highest desirable fatty acids, Δ9-desaturase and CLA desaturase indexes and the lowest atherogenicity index. The native strains inoculated as starter and adjunct cultures, grew conveniently in the cheese, developed their full potential as reflected by the profile of the metabolites released during ripening and in the global sensory perception of cheeses, and contributed thus to the development of a healthier food.

Download Full-text

Selection of Lactic Acid Bacteria for the Optimized Production of Sheep’s Milk Yogurt with a High Conjugated Linoleic Acid Content

Journal of Food Research ◽

10.5539/jfr.v6n4p44 ◽

2017 ◽

Vol 6 (4) ◽

pp. 44 ◽

Cited By ~ 1

Author(s):

Gabriela Christina Kuhl ◽

Ana Paula Gusso ◽

Brenda Lee Simas Porto ◽

Carmen Maria Olivera Müller ◽

Ricardo Ruiz Mazzon ◽

...

Keyword(s):

Lactic Acid ◽

Linoleic Acid ◽

Lactic Acid Bacteria ◽

Conjugated Linoleic Acid ◽

Streptococcus Thermophilus ◽

Linoleic Acid Content ◽

Fractional Factorial ◽

Lactobacillus Delbrueckii ◽

Bacterial Strains ◽

Sheep Milk

Thirty-five different lactic acid bacteria (LAB) strains were screened for their conjugated linoleic acid (CLA) isomers (C18:2 cis-9, trans-11 and C18:2 trans-10, cis-12) producing ability from linoleic acid (LA) in sheep’s milk. Preliminary experiments revealed that Lactobacillus delbrüeckii ssp. bulgaricus 2230 and Streptococcus thermophilus St 360 among the screened strains had the highest CLA-producing ability. This two strains were assayed in an 11-run fractional factorial design to investigate the effect of four variables included glucose, powdered sheep milk, LA and inoculum ratio on CLA production in a sheep’s milk yogurt. The optimum conditions for producing the highest levels of CLA (42.86%) were obtained by adding 10.00 mg/mL of glucose, 30.00 mg/mL of powdered sheep milk, 0.90 mg/mL of LA and a 1:2 (St:Lb) ratio of bacterial strains in the inoculum. This CLA-rich sheep’s milk yogurt could be an important supplementary food source for increasing the CLA in the human diet.

Download Full-text