Typical colonies were subjected to biochemical tests for confirmation according to the Compendium of Methods for the Microbiological Examination of Foods from the American

Public Health Association ( Labbé, 2001). After homogenization and dilution in peptone water 0.1% w/v, the slurries diluted mortadella samples were subjected to heat treatment at 75 °C for 20 min to inactivate the viable cells and activate the dormant spores. Subsequently, 1 ml aliquots of appropriate dilutions were inoculated in a series of three tubes containing culture medium Reinforced Clostridial Medium (RCM, Oxoid Ltd., England, UK) and covered with a thioglycollate agar seal (2% agar and 0.1% sodium thioglycollate) for generation of anaerobic atmosphere. The tube’s series were incubated at 37 °C for 7 days with periodic evaluations every 24 h. Tubes with characteristic growth (turbidity and gas production) were considered positive and interpreted in the appropriate MPN tables Volasertib manufacturer (Most Probable Number). The results are expressed in MPN of spores per gram of sample (MPN/g) (Scott et al., 2001). C. perfringens counts were taken in mortadella (control samples) produced without inoculum of the target organism to verify the contamination of samples, which may result in interference of the observed results. Total plate count (Plate Count Agar PCA, HiMedia, India) 37 °C for 24 to 48 h, was estimated. Treatments were arranged in split plot factorial

designs with different click here EO concentrations (0.0%, 0.78%, 1.56% and 3.125%) and nitrite levels (0 ppm, 100 ppm and 200 ppm) for the plots and times

of storage (1, 10, 20 and 30 days) for the subplot. The data were obtained from three independent experiments and the means were from triplicate results. The data obtained were subjected to analysis of variance (ANOVA), Ergoloid and the comparison between means was determined by Scott–Knott test adopting a 5% significance level. The statistical analyses of data were carried out using statistical R software (2010). The EO of winter savory (S. montana L.) was subjected to a detailed GC–MS analysis to determine its chemical composition. As shown in Table 1, 26 compounds were identified representing 99.48% of the total EO. The average extraction yield of the S. montana EO was 0.47% (4.7 ml/kg of spice dried aerial parts) in a MFB. The major groups of the compounds were monoterpene hydrocarbons and phenolic compounds. Thymol (28.99%), p-cymene (12.00%), linalool (11.00%) and carvacrol (10.71%) were found to be the major chemical constituents of the investigated EO. The observed values for the diameter of inhibition zones in determining the MIC of EO on C. perfringens are shown in Fig. 1. The evaluated variable (concentration) was significant (p = 7.25e− 06), with larger inhibition zones at higher concentrations of the savory EO. We observed formation of inhibition zones at concentrations higher than 1.