A STUDY ON SURVIVAL OF Staphylococcus aureus IN DARK AND MILK CHOCOLATE

Dark and milk chocolate bars were inoculated with Staphylococcus aureus to establish an initial population of approximately 10², 10⁴ and 10⁶ cells per gram. Samples were stored at room temperature and examined for the survival of staphylococci at 2-day intervals for the first 6 days and every 8 days thereafter. When samples were inoculated with 10² cells per gram, absence of staphylococci was observed after 2-days in dark and 14 days of storage in milk chocolate. Bars with 10⁴ cells per gram were free of cells after 38 days in dark and 86 days of storage in milk chocolate. Dark chocolate bars with 106 cells per gram, were staphylococci free after 86 days of storage; whereas the milk chocolate bars with same level of inoculation were shown to be staphylococci free after 110 days of storage