Quantitative Microbial Risk Assessment of Ready-to-Eat Marinated Soy Cheese Sold on University Campus, Jos Nigeria

Quantitative Microbial Risk Assessment (QMRA) is a scientific method used to estimate the risk of illness caused by foodborne pathogens through the consumption of contaminated food. This study determined the QMRA of ready-to-eat (RTE) marinated soy cheese sold on the University campus, Jos Nigeria. A total of 90 soy cheese samples were randomly collected from vendors, with structured questionnaires administered to consumers for consumption patterns and associated health outcomes data. A QMRA for E. coli and S. aureus was carried out using Monte Carlo simulation and the Beta-Poisson model following standard guidelines. The results revealed high total viable bacteria counts ranging from 8.16 × 10² to 8.60 × 10? CFU/g, coliforms count from 3.00 × 10² to 3.67 × 10³ CFU/g, and staphylococci count from 2.67 × 10² to 3.13 × 10? CFU/g exceeding acceptable RTE food standards. Out of 186 bacterial isolates, E. coli (25.80%) was the most occurred followed by S. aureus (20.97%) while Shigella spp. (8.06%) were the least prevalent. Self-health risk profiling showed that 73.3% of surveyed consumers reported symptoms of illnesses including; diarrhea (56.7%), vomiting (16.7%), with nausea (13.3%) as the least clinical symptoms. Key high-risk groups identified were females, individuals aged 30–35, and frequent consumers. QMRA indicated high infection probabilities for S. aureus (0.99) and E. coli (up to 0.99 annually), reflecting a cumulative risk with repeated exposure. This high infection risk associated with ready-to-eat marinated soy cheese consumption underscores the need for improved safety practices to prevent foodborne disease outbreaks.