Antimicrobial Effects of Kermanian Black Cumin (Bunium persicum Boiss.) Essential Oil in Gouda Cheese Matrix

Research on natural antimicrobial agents, especially of plant origin, highly noticed in recent years and evaluation of antimicrobial effects of native plants such as Iranian black cumin (zireh- siah) is especially important. In the present study, sensory characteristics and antimicrobial effects of Kermanian black cumin essential oil were investigated in Gouda cheese during ripening period. Extraction of the essential oil was performed by hidrodistillation.The oil was analyzed by GC using flame ionization (FID) and GC/ MS for detection.The antimicrobial effects were determined against various microbial groups (aerobic mesophilic bacteria, enterococci, mesophilic lactobacilli, enterobacteriaceae, lactococcus and yeasts). Microbial groupswere counted during ripening period using plate count on specific culture media. Organoleptic evaluation including teture, flavour, odor, colour and total acceptability were determined at the end of aging. Accordig to results, the essential oil yield was 4/1 %(W/ W). Twenty- one compounds were identified in the oil that concluded 98.97% of the total oil.The major components of Kermanian black cumin essential oil were propanal, 2- methyl- 3- phenyl (26.05 %) and gamma- terpinene (21.86 %). Generally, the increase of Kermanian black Cumin essential oil concentration led to reduction in microbial counts in different groups.The maximum antimicrobial effect was seen in yeast that reduced by 2 log compared to the control group at EO concentration of 0.4%at day 90.The minimum reduction was observed in enterobacteriaceae that showed only 0.75 log decreese compared to the control at the same concentration of EO. Addition of EO improved organoleptic properties of Gouda cheese especially in the case of flavour and odour charactristic. However, no significant differences were observed in texture and colour between treatment and control groups. Kermanian black cumin essential oil could be used as preservative material and flavouring agent in some kinds of food such as cheese and also could be provided consumers health.