The Microbial Quality of Pork Carcass during Storage

Abstract

ObjectivesTo assess the microbial quality of pork carcasses held for up to 21 d prior to fabrication.Materials and MethodsThe right sides of 20 freshly harvested pork carcasses were held in a carcass cooler for 21 d. Cooler temperature was measured every hour using a data logger. Three carcass locations (flank, shoulder, and jowl) were surface sampled on d 1, 7, 14, and 21 after slaughter using a stainless-steel meat corer. A 21.6 cm2 area corer was used to obtain flank and shoulder samples, and a 9.6 cm2 area corer was used to collect jowl samples. Each location had 4 sites that were randomly assigned for each sampling day. Meat sample cores were placed in sterile stomacher bags with 50 mL peptone water for microbiological analysis. An additional sample immediately adjacent to the shoulder incised sample was collected using the 9.6 cm2 area corer for moisture determination. The carcass pH was determined using a pH probe inserted 1.5 cm deep into the shoulder. Aerobic plate count (APC), Enterobacteriaceae (EB), yeast, and mold populations were enumerated in duplicate on petrifilm. APC data was analyzed as a randomized complete block design with repeated measures. The carcass side was considered to be a random blocking factor. Moisture and pH were analyzed as repeated measures over time with carcass side as the subject. Because the majority of observations for EB, yeast, and mold were below the detection limit (DL), these variables were analyzed as binary responses (1 = above DL and 0 = below DL) using Fisher’s exact test in SAS Proc FREQ (SAS Inst. Inc., Cary, NC).ResultsThe carcass cooler temperature averaged –0.7°C over the 21 d hanging period. The carcass surface moisture content declined (P 0.05) for APC. There was no day effect (P > 0.05) for APC; however, there was a location effect (P 0.05) for EB or mold populations, but there was a location (P 0.05) were above the DL.ConclusionPork carcass sides could be held in a carcass cooler for up 21 d at –0.7°C without compromising microbial quality.