The flavour profile of mozzarella cheese: natural vs. defined starter cultures

Quality branded (PDO) soft "pasta filata" cheese like "Mozzarella di bufala Campana" are of both scientific and economic interest because of the growing sale trend and because of problems related to protection of their quality traits. The use of the natural whey starter cultures is required by the standard of identity of the PDO cheese. Although it is one of the main factors affecting the tipicality of the product, it is also responsible for the variability of its sensory quality. Commercial defined starter cultures used for other varieties of soft Mozzarella cheese may significantly improve the hygienic quality of the product and reduce its variability but they also result in a flattening of important sensory properties with a significant reduction of consumer acceptance. In the framework of a research project whose main objectives where the standardization of the quality, the increase of the shelf‐life of water‐buffalo Mozzarella cheese, whilst protecting its typical flavour characteristics, we developed a multiple strain starter containing Lactobacillus delbrueckii ssp. bulgaricus, Streptococcus thermophilus and Lb. rhamnosus. The use of the MSS allowed to obtain an excellent product reproducibility from both the rheological and sensory standpoint. Proteolysis and aroma profile of Mozzarella cheese produced using the MSS and of control produced using the traditional technology was compared. Primary proteolysis was evaluated by UREA‐PAGE while gas‐chromatography was used to evaluate volatile organic compounds and organic acids. The control and the MSS Mozzarella cheese did not show any significant difference in the proteolytic profile, while minor differences where found in organic acids. Acetic acid content was 4 times lower in the control, in which lactic acid was slightly higher compared to the MSS cheese. Both formic and citric acid content were similar in the two cheeses. We conclude that the MSS can be used to control the variability of water‐buffalo Mozzarella cheese without negatively affecting its typical flavour.