Effect of Commercial Bioprotective Lactic Cultures on Physicochemical, Microbiological, and Textural Properties of Yogurt

Abstract

The present study investigated the effects of the commercial biopreservatives FRESHQ-11 (Lactobacillus rhamnosus), labeled as F, and HOLDBAC YM-B LYO 100 DCU (Lactobacillus rhamnosus and Propionibacterium freudenreichii subsp. shermanii), labeled as H, at different dosages on the pH, titratable acidity (%), fungal inhibition, and textural parameters of yogurt during 28 days of storage at 7 ± 1 °C. The study compared these biopreservatives with yogurt containing only the chemical preservative potassium sorbate at the maximum allowed concentration (C1) and yogurt without any chemical preservatives (C2), with the goal of identifying alternatives to reduce or replace potassium sorbate. Yogurts were formulated with biopreservatives at concentrations of 0.1% and 0.2% (v/v) and with potassium sorbate at 0.015% and 0.03%. The results indicated that yogurts containing biopreservatives had significantly lower pH and higher titratable acidity (%) than C2 (p p p L. rhamnosus was used at 0.2% v/v. This finding is promising for future pilot and industrial-scale applications.

Keywords

• lactic acid bacteria
• fermentation
• fungal contamination
• biopreservation