Abstract: The inhibitory effect of thermally processed tannic acid against Pseudomonas, B. thermosphact, Staphylococcus and Enterobacteriaceae was explored by disc diffusion method. The results indicated that thermally processed tannic acid at the concentration of 2.50% could inhibit B. thermosphact and Staphylococcus with an inhibitory zone of 22 mm. The inhibitory effects of thermally processed tannic acid, lactic acid and 75% aqueous ethanol against bacterial growth in chilled fresh pork were comparatively observed. Compared with lactic acid, thermally processed tannic acid at the same concentration exhibited better inhibitory effect against bacterial growth in chilled fresh pork. The Gompertz model was employed to describe growth parameters such as specific growth rate and lag time of microorganisms in fresh pork stored at 4℃. Increasing concentration of tannic acid revealed better antibacterial activity. However, when the concentration of tannic acid was higher than 0.63%, the increase of lag time was not obvious.

Key words: chilled fresh pork, thermally processed tannic acid, antibacterial activity, prediction model, lag time