Lee S, Norman J M, Gunasekaran S, van Laack R L, Kim B C, Kauffman R G
Department of Animal Science, Korea University, Seoul, 136-701, South Korea.
Meat Sci. 2000 Aug;55(4):385-9. doi: 10.1016/s0309-1740(99)00166-7.
This study was designed to re-examine the interrelationships among ultimate pH (pH(u)), electrical conductivity (EC) and water-holding capacity (WHC), and to test if EC, using one of two EC instruments, and pH(u) can be used to predict WHC. The % drip (PD) was used as measure of WHC. Forty-seven pork loins were classified either as PSE (pale, soft, exudative), RSE (reddish-pink, soft, exudative), RFN (reddish-pink, firm, non-exudative) or DFD (dark, firm, dry), based on L* values, PD and pH(u.) The measurement of EC, conducted using the instrument developed at the University of Wisconsin-Madison (UW-EC) was highly correlated to PD at 24 h post mortem (CD=66%), but the pH (NWK) measure of EC was not as highly related to WHC as UW-EC. The predictive value of pH(u) and EC for WHC were similar. When 47 samples were divided into three different groups, such as low (< 2% drip), medium (2-6% drip) and high (> 6% drip) drip loss, UW-EC alone grouped 80% of the samples correctly. Thus, EC seemed to be an accurate predictor of WHC in pork muscle when measured at 24 h post mortem. It is conceivable that EC can be used independently, or with even better success in combination with pH(u), to classify WHC of pork carcasses.
本研究旨在重新审视最终pH值（pH(u)）、电导率（EC）和持水能力（WHC）之间的相互关系，并测试使用两种EC仪器之一测得的EC和pH(u)是否可用于预测WHC。用滴水损失百分比（PD）作为WHC的衡量指标。根据L*值、PD和pH(u)，将47块猪里脊肉分为PSE（苍白、柔软、渗出）、RSE（微红、柔软、渗出）、RFN（微红、坚实、不渗出）或DFD（暗黑、坚实、干燥）四类。使用威斯康星大学麦迪逊分校开发的仪器（UW-EC）进行的EC测量与宰后24小时的PD高度相关（相关系数=66%），但EC的pH（NWK）测量值与WHC的相关性不如UW-EC高。pH(u)和EC对WHC的预测价值相似。当将47个样本分为低（滴水损失<2%）、中（滴水损失2-6%）和高（滴水损失>6%）三个不同组时，仅UW-EC就能正确地将80%的样本分类。因此，宰后24小时测量时，EC似乎是猪肉肌肉中WHC的准确预测指标。可以想象，EC可以单独使用，或者与pH(u)结合使用时效果更好，用于对猪胴体的WHC进行分类。
