Growth of Salmonella typhimurium and Staphylococcus aureus in Retail Pumpkin Pies1
The ability of pumpkin pies as prepared and distributed in the food distribution system to support growth of selected food pathogens was studied. Products were puchased from a cross-section of retail outlets. Microbial quality of the products was determined. One of four samples contained high levels of coliforms and Staphylococcus aureus. Salmonella was not detected in any of the samples. Samples were inoculated with Salmonella typhimurium and S. aureus and incubated at 4, 25 and 35 C. Water activity (aw), pH and S. aureus enterotoxin were measured. Pumpkin pies supported growth of the pathogens at 25 and 35 C. Data revealed if contaminated and held at room temperature, pumpkin pies could present a public health hazard. Growth of pathogens is inhibited at refrigeration temperatures. Enterotoxin was present in samples containing S. aureus. Potassium sorbate (0.25%) inhibited growth of S. typhimurium but not S. aureus. Refrigeration is recommended for pumpkin pies to eliminate the possible health hazard.