Bacteriological evaluation of soft cheese sold for human consumption in ado-ekiti, Nigeria

Background: Dairy products strongly enhance the growth of microorganisms. Soft cheese sold in Ado-Ekiti are mostly prepared locally and hawked by women who are mostly illiterates. The paucity of information on health safety of consumers of the local cheese necessitates this study. The prevalence, microbial load and antibiotic sensitivity pattern of isolated bacteria were investigated. Methods: Twenty samples of soft cheese randomly collected from various hawkers were processed. One gram of the curd was homogenized in 9 ml of peptone water and 0.1 ml of various dilutions from 10-1 to 10-6 was plated on standard media. Aerobic plate count, total coliform count and other bacteria count were enumerated after culture. The antibiotic susceptibility pattern of isolated organisms was evaluated using disk diffusion method. Results: The mean aerobic plate count of bacteria and the total coliform count were 6.8 x 107 and 3.7x107 respectively. The most prevalent organism was Escherichia coli 18 (90%) followed by Klebsiella pneumoniae 14 (70%), Pseudomonas aeruginosa 12 (60%), Salmonella typhi 6 (30%), Staphylococcus aureus 5 (25%) and Bacillus cereus 5 (25%). The mean colony forming unit/g of cheese was highest in Escherichia coli (8.2x106), followed by Klebsiella pneumoniae (6.4x106), Pseudomonas aeruginosa (9.3x105), Staphylococcus aureus (6.9x104) and Bacillus cereus (4.6x104). Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Bacillus cereus were susceptible to ofloxacin and ciprofloxacin. Salmonella typhi and Staphylococcus aureus were susceptible to ceftaxidime, cefuroxime, gentamycin, ofloxacin and ciprofloxacin. Conclusion: Local cheese sold in Ado-Ekiti may not be safe for human consumption.