The Prevalence And Growth Potential Of Some Salmonella Species In Kitfo And Effect Of Kitfo Preparation Processes On The Test Organisms

In an attempt to assess the microbial load and the prevalence of salmonellae in "kitfo", a total of 50rnraw or "Tire kitfo" samples were collected from ten food establishments (hotels, restaurant and bars)rnfrom different areas of Addis Ababa. The microbial load in "tire kitfo" samples collected from allrnsources was markedly high. The highest average loads of aerobic mesophilic bacteria (8.33rnLog(CFUlg», coliforms (6.77 Log(CFUlg», staphylococci (7.29 Log(CFUlg», lactic acid bacteriarn(5.37 Log(CFU/g», molds and yeasts (5.96 Log(CFUlg», and aerobic spores (5.67 Log(CFUlg»rnwere encountered in "kitfo" from three hotels and one bar. On the other hand, the lowest averagernloads of aerobic mesophilic bacteria (7.30 Log(CFU/g», coliforms (4.51 Log(CFU/g»,rnstaphylococci (6.18 Log(CFU/g», lactic acid bacteria (4.10 Log(CFU/g», molds and yeasts (4.06rnLog(CFUlg», and aerobic spores (3.71 Log(CFU/g» were found from one restaurant and twornhotels. Variation within samples in counts of coliforms, staphylococci, lactic acid bacteria, moldsrnand yeasts, and aerobic spores was significant in all or most establishments (CV> 10%). However,rncounts of staphylococci and lactic acid bacteria did not show marked variations among hotels,rnrestaurant and bars. Variation within samples in the count of aerobic mesophilic bacteria in mostrnfood establishments was not significant (CV < 10%). The microbial load of slightly cooked "kitfo"rn("Iebleb kitfo") was found to be high, though it was less than that of raw or "tire kitfo". Variation inrnthe counts of aerobic mesophilic bacteria, staphylococci and lactic acid bacteria in "lebleb kitfo"rnatllJHg ten establisluIleIlts was liul slgiiincalit (CV ~ 10%), while thaI of coliforms, molds and yeasts,rnand aerobic spores was significant (CV> 10%). No microorganisms have been detected from "tibsrnkitfo", except very few aerobic spores. From the study of the prevalence of Salmonella in "kitfo"rntwenty one positive samples were obtained from the 50 samples collected from the above hotels,rnrestaurant and bars. Among these positive samples of Salmonella, the highest number of positivern';)«IHpJ"''' • ..I 1HUIl!'1'-''' "J.o II)) n"'l1. .... llVlll .... "'1,,11 VI -l.A.Vl ..... l.L1 UIiU .LIUl ..", UIlU Lll'; JVW .... .,l HUIllU1.,.J Virnpositive samples (one) was from Hotel G. No Salmonella was isolated from "kitfo" of Hotel D, Ernand Restaurant A. No Salmonella was encountered in "lebleb" and "tibs kitfo" samples. Of thernthree selective enrichment broths, i.e. Selenite Broth, Thetrathionate Broth, and Rappaport- VassiliadisrnMedium used for enriching the growth of Salmonella species, RVB was found to be superior. Of thernfour plating media, i.e., Salmonella-Shigella (SS)agar, MacConkey agar, Brilliant Green agar (BG) andrnXylose Lysine Desoxycholate (XLD) medium, BG was found out to be superior in supporting therngrowth of salmonellae encountered in this work. The microbial load of swabs from raw beef wasrnrelatively low when compared to that of "kitfo". The loads of aerobic mesophilic bacteria, coliforms,rnstaphylococci, lactic acid bacteria, molds & yeasts and aerobic spores were found to be 5.07rnLog(CFU/cm'), 2.34 Log(CFU/cm'), 3.14 Log(CFU/cm'), 2.63 Log(CFU/cm'), 2.54 Log(CFUlcm'),rnand 2.60 Log(CFU/cm'), respectively. When assessing the growth potential of Salmonella species inrn"kitfo", they were found to grow weI!. They grew to the level of 7.0 Log(CFU/g) within 12h ofrnincubation.

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