Methods of Chilling and Packaging of Beef, Pork and Lamb Variety Meats for Transoceanic Shipment: Microbiological...

The effect of various initial chilling treatments on the numbers and types of microorganisms of beef, pork and lamb tongues (n = 60) and livers (n = 60) packaged either in polyethylene (PE) film or in vacuum packages in Texas and transported fresh-chilled via transoceanic shipment to Antwerp, Belgium, was evaluated. Initial chilling treatments included: cooler-tempered (4 to 6 h at 2°C), cooler-chilled (24 h at 2°C) freezer-tempered (0.5 to 1 h at -20°C), freezer-chilled (2 h at -20°C), ice-chilled (2 h in ice water slush) and no prechilling (NPC) before packaging and subsequent refrigerated storage at 2°C. After the initial chilling treatments, the microflora was varied with Micrococcus spp. with or without coryneform bacteria being the predominant bacterial types of most samples. After refrigerated storage for 13 to 15 d, lactic acid bacteria became dominant in most vacuum-packaged samples and in pork and lamb samples stored in PE film. Brochothrix thermosphacta and Pseudomonas spp. constituted a greater part of the microflora of beef tongues and livers stored in PE film than that of comparable vacuum-packaged samples. Increases in aerobic plate counts (APC) of refrigerated vacuum-packaged samples nearly always were greatest for samples (NPC) that were not pre-chilled before packaging and usually were smallest for samples that were either freezer-chilled, freezer-tempered or ice-chilled.