Food Safety and Sanitation
Temperatures
Danger zone: 41–135°F (5–57°C). Cool cooked foods from 135 to 70°F within 2 hours and to 41°F within 4 more (6 total). Reheat to 165°F within 2 hours. Cold hold at 41°F or below; hot hold at 135°F or above. Cool in shallow pans, use ice baths, and avoid stacking hot containers.
HACCP and hygiene
HACCP has seven principles; critical control points are where control prevents, eliminates, or reduces a hazard. Clean removes soil; sanitize reduces microbes; use correct concentration and contact time. Sanitizer test strips verify concentration. Prevent cross-contact for allergens (milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soy, sesame). Handwashing is the single most important practice; wash for at least 20 seconds. Store raw proteins below ready-to-eat foods. Use time as a public health control only with written procedures and labels.
Traps
Questions test 40 vs 41°F, sanitizer too strong or too weak, bare-hand contact with ready-to-eat food, and “sanitizing” a visibly dirty surface.
Worked example
Calibrate a thermometer in ice water at 32°F; adjust to zero. Rule: if a cream pie or custard has been above 41°F for more than 4 hours, discard it.