• Luo, Xin
• Mellor, Glen
• Li, Yutao
• Frank, Damian
• Zhang, Yimin
• Chen, Xue
• Stark, Janet
• Kaur, Mandeep
• Hughes, Joanne

Abstract

The shelf life of vacuum packaged chilled beef (VPCB) can be defined as an arbitrary microbiological limit or when the organoleptic quality becomes unacceptable. While there is no universally accepted definition of shelf life, excellent temperature control throughout the supply chain is essential for a high quality product. The robustness of temperature control within Chinese distribution networks was tested using Australian VPCB. Half striploins (Longissimus lumborum) from 40 steer carcasses were vacuum packaged and randomly allocated for export to three Chinese destinations and to a CONTROL treatment stored under ideal temperature conditions (~-1 oC) in Australia.Temperature loggers measured the temperature of VPCB until pack opening. Meat biochemistry (pH, Minolta tristimulus color), total aerobic plate counts (APC), total lactic acid bacteria (LAB), total volatile basic nitrogen (TVB-N) and extensive sensory testing on the raw meat was performed at 84, 98, 120 and 140 days postslaughter. The temperature was generally well maintained at -1 oC during shipping and at Chinese distribution centers, however temperature deviations negatively affected the sensory scores of some VPCB. APC and LAB did not increase consistently over the storage period and ranged between 5.98 – 7.78 log10 cfu/cm2 and 5.89 – 7.18 log10 cfu/cm2 respectively. The sensory scores of the CONTROL and Chinese VPCB did not indicate spoilage at 140 days, however TVB-N was higher than 15 mg/ 100 g in most Chinese samples. TVB-N was a good predictor of the sensory attributes in the VPCB compared to absolute microbial counts. This study showed that extended shelf-life was achieved for Australian VPCB with appropriate temperature control and highlighted the inadequacy of total microbial counts as shelf life markers.

Topics

• impedance spectroscopy
• Nitrogen