HYGIENIC EFFECTS OF TEUCRIUM POLIUM ESSENTIAL OIL AGAINST SALMONELLA TYPHIMORIUM LT2 IN PROBIOTIC YOGHURT

The aim of this study was to evaluate the probability to produce yoghurt containing live and active probiotic microorganisms as functional food with favorite sensorial properties. The maintenance of Salmonella as a pathogen agent was evaluated under the synergistic effects of simultaneous presence of Teucrium polium essential oil (EO) and Lactobacillus acidophilus. For this purpose, 108-109 CFU/ml of L. acidophilus, 103 CFU/ml Salmonella Typhimurium LT2, and different concentrations of Teucrium polium EO were added to yoghurt. The products were kept for 28 days in 4°C refrigerator and evaluated for changes in organoleptic properties and the maintenance of L. acidophilus and S. Typhimurium LT2. The presence of bacteria was determined by culture in selective media and PCR methods. T. polium EO had the best Salmonella growth inhibition at 60 ppm and 80 ppm and in synergistic combination with L. acidophilus. No Salmonella was isolated during the 28 days of preservation of probiotic yoghurt or probiotic yoghurt containing different concentrations of T. polium EO. However, Salmonella could be isolated and counted in days 1 and 7 from negative control group and the groups containing T. polium EO. The best organoleptic properties of essential oil concentrations were observed in groups containing L. acidophilus. Using the combination of T. polium EO and L. acidophilus improved the hygienic and organoleptic quality of yoghurt.