Effect of ozone and potassium lactate on lipid oxidation and survival of Salmonella typhimurium on fresh pork.

The objective of this research was to evaluate the effect of ozone gas and potassium lactate on lipid oxidation and survival of Salmonella typhimurium on fresh pork. A total of 144 samples of fresh pork samples were cut into pieces approximately (8x5x0.6) cm in size, then (0, 2 and 4%) potassium lactate (KL), inoculated with S. typhimurium was applied by spreading a 0.5 mL cell suspension over each sample. The pork samples were then packed in (6"x8") airtight polyethylene bags with a thickness of 87.5 microm and a volume of 3.5 L with and without ozone. Ozone gas was injected into the plastic bags at a rate of 0, 200, 500 and 1,000 mg h(-1) and the samples later stored at 8 degrees C. Thio-barbituric Acid Reactive Substance (TBARS) and microbial loads were determined on days 0, 5, 10 and 15. Data was statistically analyzed using SPSS software and differences among means detected at the 0.5% confident level using the Scheffe's test. Samples treated with 2 and 4% KL had significantly (p<0.01) lower TBARS value than non-treated samples. Combination of ozone and KL showed inhibitory effects on S. typhimurium in samples. S. typhimurium was sensitive to 4% KL with and without ozone. At 1,000 mg h(-1), ozone improved KL inhibitory effect on S. typhimurium. Ozone and KL are potential substances for inhibition of S. typhimurium.