Effect of ‘in situ’ produced bacteriocin thermophilin T on the microbiological and physicochemical characteristics of Myzithra whey cheese

Abstract

Myzithra whey cheese was made by the addition of ovine milk (10%) to whey, previously fermented by the bacteriocinogenic strain Streptococcus thermophilus ACA‐DC 0040, resulting in production of a bacteriocin (thermophilin T) titre at a concentration 40 960 ± 2560 AU/mL. The final antimicrobial activity in the ready‐to‐eat cheese was sufficient to inhibit the growth of coliforms and restrict the growth of bacteria of the Micrococcus group, thus contributing to and increased shelf life and the safety of cheese. A lower lactose content was observed in the cheese, which would lead to better acceptance by lactase‐deficient consumers. Moreover, the sensory characteristics of the cheese remained unchanged during the whole cold storage period, ensuring an extended shelf life.