Effect of storage temperature on the chemical, microbiological, and sensory characteristics of pasta filata soft cheese containing probiotic lactobacilli

The aim of this study was to manufacture pasta filata cheeses added with two probiotic lactobacilli: Lactobacillus rhamnosus GG and Lactobacillus acidophilus LA5, either individually or combined, and to evaluate the effect of the storage temperature (4 and 12 °C) on their chemical, microbiological, and sensorial characteristics. Three cheese types were made: (i) G: containing L. rhamnosus GG, (ii) L: containing L. acidophilus LA5, and (iii) GL: containing both probiotic strains. Gross composition, pH, microbiological, and sensory characteristics were determined. No differences in gross composition were found among them. pH values remained above 5.2 in cheeses stored at 4 °C. However, a postacidification was observed in cheeses ripened at 12 °C. L. acidophilus LA5 was not able to grow, while L. rhamnosus GG grew 1.5 log 10 CFU/g in G and GL cheeses stored at 12 °C, reducing the pH from day 8 onwards. These results emphasize the importance of the storage temperature since the good characteristics of probiotic cheeses are kept if the cold-chain is respected. Thus, the selection of probiotics, together with the food matrix and the starter, should be carefully evaluated.