In vivo study of the immunomodulatory capacity and the impact of probiotic strains on physicochemical and sensory characteristics: Case of pasta filata soft cheeses.

Nowadays, there is a great interest of food industries on the development of innovative dairy products containing probiotic bacteria. Beyond yoghurt, cheeses could be a suitable matrix for the incorporation of probiotics. This work aimed to study the impact of the addition of two probiotic lactobacilli (L. rhamnosus GG and L. acidophilus LA5), either individually or combined, on the physicochemical and sensory characteristics of pasta filata soft cheeses and to evaluate the immunomodulating capacity of the product using an in vivo model. Four cheese types were produced: CC (control cheese); L-C (added with L. acidophilus LA5); GG-C (added with L. rhamnosus GG) and GGL-C (added with both probiotics). No differences in gross composition were found. An increase in secondary proteolysis was observed in GGL-C cheeses which correlated with a greater bitter and aftertaste. On the contrary, the L-C cheese received the highest overall quality score. The translocation assay was negative. Moreover, the three experimental cheeses were able to modulate the immune system of mice by reducing the secretion of pro-inflammatory cytokines in the intestine, downregulating the levels of interleukin (IL)-10 and increasing the secretion of Secretory Immunoglobulin A (S-IgA). No synergistic effect was detected when both probiotics were added.