Food Safety
What this domain tests
Food Safety questions test hazard identification, hygiene practice and preventive systems. The WBPSC Food Sub-Inspector role is inspection-oriented, so expect practical scenarios on temperature control, cross-contamination, HACCP and foodborne illness.
Core rules and concepts
- Hazards are biological (bacteria, viruses, parasites), chemical (pesticides, mycotoxins, cleaning agents) and physical (glass, metal, stones).
- The danger zone is 5°C to 60°C; keep hot food above 60°C and cold food at or below 5°C.
- HACCP has seven principles: hazard analysis, determine CCPs, set critical limits, monitor, take corrective action, verify and keep records.
- HACCP is preventive; end-product testing alone is not HACCP.
- Separate raw and cooked food, use potable water, wash hands, control pests and exclude infected food handlers.
- Aflatoxin comes from Aspergillus flavus, often in groundnuts and cereals; histamine can form in spoiled fish.
Worked example
Cooked rice is left at 30°C for six hours before serving. That is inside the danger zone, so spores of Bacillus cereus can germinate and produce toxin. Reheating may kill vegetative cells but does not reliably remove the toxin. The safe control is to cool quickly and refrigerate within two hours, then reheat thoroughly once.
Traps that cost marks
Freezing does not kill bacteria. Reheating does not destroy all toxins. HACCP is not a licence or a laboratory test. Allergen cross-contact can occur through shared utensils even when food looks clean.