This study was undertaken to investigate the effects of selected essential oils on viability of Salmonella in çiğ köfte, a commonly consumed snake food in Turkey containing raw ground beef. Çiğ köfte was prepared by a local restaurant, inoculated with high levels of 5-strain mixture of Salmonella (6.50log10cfu/g), and then divided into 6 groups. Each group was treated with 1.8% levels of normal saline (control), carvone, cineole, eugenol, linalol, or limonen. Treated batches were stored at 4°C for 3h. Duplicate samples were taken from each group 30min and 3h after treatment for enumeration of Salmonella using XLD agar. Results indicated that regardless of the sampling interval, the numbers of Salmonella were significantly reduced in all treatments except in control and limonen treated samples. Salmonella numbers were reduced to 6.43, 4.77, 5.33, <1.0, 3.90 and 6.34 log10cfu/g in control, carvone, cineole, eugenol, linalool, and limonene groups, respectively. The numbers of pathogen were decreased below of the detection limit even, after 30min in eugenol treated samples. In a second experiment, a batch of çiğ köfte was inoculated with Salmonella (6.45log10 cfu/g) and divided into 5 groups for treatments with eugenol at the levels of 1.8%(v/w), 1.5%, 1.0%, 0.5% or remained untreated (control). The pathogen was enumerated from duplicate samples 1h after treatment. Results indicated that pathogen numbers were decreased to <1.0, 2.60, 3.78 and 5.45log10 cfu/g in çiğ köfte samples treated with 1.8%,1.5%,1.0% and 0.5% eugenol, respectively and to 6.31 log10 cfu/g in control. These results revealed that essential oils, especially eugenol, may be used for non-thermal inactivation of Salmonella in foods that do not have an actual bactericidal step in such as çiğ köfte, after evaluation of their potential sensory effects .
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