Investigation growth and survival of some pathogens in koumiss

ABSTRACT Investigation Growth and Survival of Some Pathogens in Koumiss Aim: This study was aimed to investigate growth and survival of Escherichia coli O157:H7 ATCC 43894, Listeria monocytogenes ATCC 7644 and Staphylococcus aureus NCTC 10654 in koumiss, produced from raw mare milk, during the fermantation. Material and Method: Escherichia coli O157:H7 (Group 1), Listeria monocytogenes (Group 2) and Staphylococcus aureus (Group 3) were added to the raw mare milk which would used for producing koumiss and with this three pathogen microorganisms (Group 4) was inoculated at the level of 106 cfu/ml. During the fermentation, microbiological and chemical analyses were performed by taking one sample, 1st, 5th and 24th hours and on the 2nd, 3rd, 4th and 5th days, from each of the groups. Inoculation of pathogenic microorganisms were carried out by adding starter culture and subjecting to the fermentation at 25°C. Results: It was observed that pH rate, dry matter and protein amount decreased, while titration acidity and alcohol amount increased throughout fermentation. It was observed that there was positive correlation between total aerobic mesophilic bacteria, psychrophilic aerobic, enumeration of Lactobacillus spp. and the pathogen microorganisms while there was negative correlation with enumeration of yeast and mould. That the number of pathogenic microorganisms deveased throughout fermentation. Escherichia coli O157: H7, Listeria monocytogenes and Staphylococcus aureus were completely destroyed on the second day of fermantation process. Conclusion: It was determined that the pathogenic microorganisms were completely inhibited on the second day of the fermentation. It is concluded that this situation was relevant with the increase of the titration acidity and alcohol amount, and decreasing pH level. Koumiss, produced from raw mare milk may cause public health issues until the second day of fermentation and it is recommended that the producers should pay attention to better production methods and their awareness might be raised.