Inhibitory effects of spices essential oils on Salmonella spp. ve Staphylococcus aureus pathogens in meat

The purpose of this study was to evaluate the antimicrobial effect of Origanum onites, Ocimum basilicum ana Syzygyum aromaticum essential oils (EOs) against two strains of Salmonella serovar Typhimurium or Staphylocococus aureus in minced beef meat (20% fat) stored at +4ºC during seven days. The effects of EOs on meat color, pH and sensory properties was also determined.For this purpose, MIC (minimum inhibitory concentration) values of EOs were determined by agar dilution method. Seven different concentrations of (0,03%, 0,06%, 0,12%, 0,25%, 0,5%, 1% and 2% (w / w)) EOs were used. MIC value of Origanum onites and Ocimum basilicum EOs were found as 0,06% and 0,25% (w / w) on Salmonella serovar Typhimurium, respectively. Also it was determined as 0,03 % and 0,025% (w / w) on Staphylocococus aureus. MIC value of Syzygyum aromaticum was found higer than higest concentration that used that?s why only Origanum onites and Ocimum basilicum EOs were used in inoculation trials. Salmonella Typhimurium and Staphylocococus aureus counts were increased during storage period in all EO concentrations except 1 and 2%. 2% of both EO was found most effective concentration. Origanum onites EO had more antimicrobial activity than Ocimum basilicum EO on Salmonella Typhimurium and Staphylocococus aureus. While 2% of Origanum onites EO concentration showed 3,16 log reduction, 2% Ocimum basilicum EO showed 2,48 log reduction on S. Typhimurium during 7 days at +4ºC storage in minced beef meat. S. aureus was increased in all concentrations during storage period, however counts were 1,01 log and 0,79 log lower than control for 2% concentration of Origanum onites and Ocimum basilicum respectively.Acording to statistical results, EOs had significant effect (P<0,05) on meat color and pH during seven days at +4ºC storage. Moreover, addition of high concentration of EOs have adversely affected the sensory properties of meat balls.