Premium
EFFECT OF WATER ACTIVITY ON THE GROWTH OF STAPHYLOCOCCUS AUREUS AT MEAT‐CHEESE INTERFACES
Author(s) -
RAJKOWSKI KATHLEEN T.,
SCHULTZ FRANKIE,
NEGRON FLOR,
DICELLO ANTHONY
Publication year - 1994
Publication title -
journal of food safety
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.427
H-Index - 43
eISSN - 1745-4565
pISSN - 0149-6085
DOI - 10.1111/j.1745-4565.1994.tb00595.x
Subject(s) - staphylococcus aureus , food science , moisture , water activity , contamination , chemistry , vacuum packing , bacterial growth , snack food , water content , biology , bacteria , ecology , genetics , geotechnical engineering , organic chemistry , engineering
There is increased marketing of ready‐to‐eat nonrefrigerated snack foods which consist of meat or sausage products with low or intermediate moisture levels combined with high moisture food products, i.e., cheese products. Packaging the intermediate moisture meat in direct contact with a high moisture food might change the water activity (a w ) of the products sufficiently to support growth of Staphylococcus aureus at contaminated interfaces. To evaluate this possibility, sterile sausage slices (a w = 0.60 to 0.82) were surface inoculated with log 2‐3 CFU/g of S. aureus, interfaced with processed cheese slices (a w = 0.94), vacuum packaged, and incubated at 19, 28, 37C and at cyclic temperature of 19–37–19C. S. aureus levels and water activities were determined weekly for 0 to 9 weeks. The a w at the interface changed rapidly and reached an a w that supported S. aureus growth. Growth of S. aureus occurred under all test conditions when the samples were stored at 28 and 37C. At 19C storage S. aureus remained viable for the length of the study.