A Study on the Factors Affecting the Growth of Staphylococus Aureus Strains and Enterotoxin Production in Cream Pastries

Abstract

In this study, the growth and enterotoxin production abilities of enterotoxigenic S. aureus strains In cream pastries were investigated. The cream was inoculated with enterotoxigenic S. aureus strains, which produce A (SEA 10652 FDA 196E), B (SEB 10654 FDA 243), C (SEC 10655 137) and D (SED 10656 494) type toxins as mixtures at 10(3), 10(4) and 10(5) cfu/g levels. Cream pastry samples produced with these cream mixtures were stored at 4degreesC, 10degreesC, 18degreesC, room temperature (23-26degreesC) and 30degreesC for 48 hours. The samples taken after 2, 6, 12, 24 and 48 hours during this experiment were analysed microbiologically, physicochemically and serologically. None of the strains produced enterotoxin in cream pastry samples contaminated at 10(3) cfu/g and stored at 4degreesC, 10degreesC and 18degreesC. Enerotoxin A, B, C and D were determined at 30degreesC after 12, 18, 48 and 24 hours, respectively. At room temperature enterotoxin C was not detected but enterotoxin A and D were observed after 24 hours, while the observation time was 48 hours for enterotoxin B. In cream pastry samples contaminated at 10(4) Cfu/g and stored at 18degreesC, only entrerotoxin A was detected after 48 hours. In the samples stored at room temperature, A, B, D and C were observed after 12, 18, 24 and 48 hours, respectively. At 30degreesC, enterotoxin A, B, D and C were detected after 6, 12, 18 and 24 hours, respectively. In the other cream pastry samples contaminated at 105 cfu/g and stored at 18degreesC, entertoxin A was observed after 24 hours. At room temperature enterotoxin A and B were observed after 12 hours and enterotoxin C and D were observed after 18 hours. At 30degreesC, enterotoxin A and D were detected after 6 hours and enterotoxin B and D were detected after 12 hours. Therefore, considering that especially S. aureus strains producing enterotoxin A can produce toxins at low temperatures, it is very important to store food products containing these types of strain in cold conditions and to take necessary precautions in order to prevent contamination with S. aureus strains which produces enterotoxin. Furthermore, necessary hygienic measures should be taken by considering S. aureus strains, especially those producing A type enterotaxin.