Effects of Autochthonous Starter Cultures on The Behavior of Staphylococcus au-reus During The Production of a Semi-Dry Fermented Sausage

Staphylococcus aureus can grow and produce enterotoxin during the production of fermented sausages, especially in the early stage of the fermentation. Furthermore, staphylococcal enterotoxins are heat-stable. Therefore, inhib-iting the growth of this pathogen during production is of great importance for food safety. The study was carried out to determine the effects of autochthonous lactic acid bacteria (LAB) strains (Lactiplantibacillus plantarum S91, Latilactobacillus sakei S15 and Pediococcus acidilactici S147b) on the behavior of S.aureus in heat-treated sucuk (HTS) (raw fermented cooked and dried), a type of semi-dry fermented sausage. The HTS batters were inoc-ulated with S. aureus ATCC 51740 (SEB) at 105 CFU/g level. In groups containing L. sakei S15, pH decreased faster in the first 24 h of fermentation (22 °C) than in other groups. After 48 h, pH dropped below 5.0 in all groups with autochthonous strains, while it was still above 5.5 in groups without autochthonous strains. Therefore, while the number of S.aureus increased during fermentation in the sausage group without autochthonous strains, there was no significant change in the number in the presence of autochthonous strains. The heat treatment (core tempera-ture; 68 °C) caused significant reductions in S. aureus, LAB and Micrococcus/Staphylococcus (< 2 log CFU/g). At the end of drying (18 °C), the aw value varied between 0.927 and 0.935. Staphylococcal enterotoxin was not de-tected in all groups. In conclusion, the rapid decrease in pH during the early stage of fermentation is an important hurdle effect in the controlling the growth of S. aureus.