Bacteriological quality and occurrence of Escherichia coli and Staphylococcus aureus in ice cream sold in Zaria, Kaduna State Nigeria

A cross-sectional study was conducted across Zaria metropolis to determine the bacteriological quality and occurrence of Escherichia coli and Staphylococcus aureus in ice cream sold to consumers by supermarkets and street traffickers. A total of 240 samples comprising 111 industrially and 129 locally produced ice creams were examined for the Total Aerobic Plate and Coliform Counts for S. aureus and E. coli and identification of the isolates were done using conventional biochemical characterization and Microbact test. The isolate were further subjected to antimicrobial susceptibility test by disk diffusion method. Of the 240 samples, 19 (8.0%) were positive for S. aureus and 5 (2.0%) were positive for E. coli ; 5 (26.3%) of the S. aureus isolates were from industrially produced ice cream while 14 (73.6%) were from locally made ice cream with a statistically significant (P < 0.05). Overall, the mean Total Aerobic Plate Counts (TAPC) per ml of industrial and locally produced ice cream were 1.14 X 10 7 and 2.02 X10 7 respectively with a statistically significant difference (P < 0.05) and the mean counts for Total Coliform Count (TCC) per ml for industrial ice cream and local ice cream were 5.69 X 10 3 and 4.73 X 10 3 respectively. Brands of ice cream of industrially produced origin had significantly lower of S. aureus and E. coli load than those of local sources. Antibiotic susceptibility profile for S. aureus showed that all the isolates were resistant to multiple antibiotics. Antibiotic susceptibility profile for E coli showed that all the isolates were resistant to one or more antibiotics except for Nitrofurantoin and Ciprofloxacin. Locally produced ice creams sold in Zaria appear to pose a higher health risk to consumers compared to industrially produced ice cream. It is imperative that bacteriological standards be enforced in order to prevent ice cream borne infections in humans. There is a need also to control antibiotic usage among dairy farmers and continuous surveillance of antimicrobial resistance trends on animals from which ice cream is sourced.