Microbiology of Delicatessen Salads

Abstract

Prepared salads obtained from 11 convenience food manufacturers in eight geographical locations throughout the United States were examined microbiologically upon their arrival at the laboratory, stored at 2 C and examined microbiologically weekly thereafter for 5 weeks. Microbiological evaluation included determination of total plate count, coliforms, fecal coliforms, yeasts and molds, Clostridium perfringens, Staphylococcus aureus. and salmonella; pH of the salads also was measured. Microorganisms of public health significance were detected initially in few samples; during storage these microorganisms decreased in number and no longer could be detected. Yeasts and molds, and microorganisms enumerated by the total plate count consistently proliferated to extremely high numbers in shrimp, macaroni, carrot and raisin, and egg salads. Additionally, 64 prepared salads representing 13 convenience food manufacturers from 10 geographic locations were examined microbiologically for compliance with Army and Air Force Exchange Service microbiological limits. Counts in excess of the limits were found in 36 of 64 (56%) samples; violations in total plate count, coliform, and yeast and mold limits occurred in 16, 22, and 45% of the samples, respectively.