The calibration temperature of pH-glass electrodes: significance for meat quality classification

In this short communication we show important factors concerning pH measurements in pork. The purpose of the study was to investigate the effect of the calibration temperature of pH-buffer and of the pH-electrode on pH measured 1–120 min post mortem in pork, and to evaluate its significance for prediction of meat quality. The calibration temperature of pH-electrodes as well as the sample temperature is essential for pH measurements, as pH measurements are highly temperature-dependent. This is especially important when using pH measurement for prediction of meat quality or when different experiments are compared. We have used two calibration temperatures of 15 °C (normal) and 35 °C (modified) in the present investigation. Based on our findings, we therefore recommend a buffer and electrode temperature of 35 °C as a standard procedure for measuring pH early post mortem. As a minimum the pH should be presented along with the measuring and calibrating temperatures.