A Case Study of a School Foodservice Cook-Chill Operation to Develop a Hazard Analysis Critical Control Point Program

A case study was conducted of a school food service cook-chill operation to establish a Hazard Analysis Critical Control Point (HACCP) program for four ground beef entrees. Focus groups assessed employee knowledge and attitudes about cook-chill production, food safety, and HACCP. Managers were knowledgeable about food safety but cited lack of time as an impediment to implementation. Time and temperature measurements documented cooking, chilling, reheating, and serving functions. Product internal temperatures reached 184.5 ± 5.9°F prior to chilling. Blast chilling cooled products to 40°F within 2.0 ± 0.8 h. On reheating, product temperature reached 184.9 ± 10.6°F in 40.0 ± 17.9 min. A holding temperature of >140°F was sustained for 71.4 ± 4.5 min. 

Environmental sanitation was analyzed using adenosine triphosphate bioluminescence. Inconsistencies signified the need to establish standard sanitation practices. Microbiological tests included aerobic plate count (APC), total coliforms, Escherichia coli spp., E. coli O157:H7, Salmonella spp., Staphylococcus aureus, and Clostridium perfringens. All tests were negative for E. coli O157:H7. Raw ground beef contained Salmonella spp., S. aureus, C. perfringens, an APC of 2.4 x 10⁵ ± 4.3 x 10⁵ CFU/g, a total coliform count of 3.6 x 10² ± 5.3 x 10² CFU/g, and an E. coli count 3.3 x 10² ± 6.9 x 10² CFU/g. Cooking reduced the APC by 3 to 4 log cycles and eliminated total coliforms and E. coli Salmonella spp., however, survived processing or reappeared through recontamination.