Introduction to Food Safety & Sanitation Management – Hazards to Food Safety
Learning Outcomes
- Upon completing this lesson, you should be able to:
- Identify population groups that are most susceptible to acquiring food-borne illness (FBI) such as the young, elderly, pregnant women & immunocompromised individuals (YOPI).
- Recognize and cite the major food-safety laws and regulations in the Philippines and abroad (e.g., Philippine Food Safety Act of 2013 – R.A. 10611, Codex Alimentarius, U.S. FDA Model Food Code, HACCP, ISO 22000).
- Classify the different hazards to food safety (biological, chemical, physical) and describe appropriate preventive controls.
Potentially Hazardous Foods (PHF) / Time & Temperature Control for Safety (TCS)
- Definition: Foods that support rapid & progressive growth of infectious or toxin-producing microorganisms; therefore require strict time–temperature control.
- Typical intrinsic factors of a PHF:
- High PROTEIN and/or high CARBOHYDRATE content.
- pH above 4.6 (low acidity).
- Water activity ( a_w ) above 0.85 (slide typo showed 8.5; correct food-science threshold is 0.85).
- Common examples: red meat, poultry, raw shell eggs, shellfish, dairy products, cooked rice or potatoes, refried beans, tofu, cut melon/cantaloupe, cooked vegetables.
Temperature Danger Zone (TDZ)
- Regulatory range: 41^\circ F \; (5^\circ C) to 140^\circ F \; (60^\circ C).
- Rule of 4 hours: Total cumulative time PHF spends in the TDZ must not exceed 4 h; beyond that food is discarded.
- Microbial growth in the TDZ is exponential, doubling roughly every 20 minutes under ideal conditions.
Ready-to-Eat (RTE) Foods
- Foods edible without any further washing, cooking, or preparation.
- Highly vulnerable because no kill-step is applied after handling.
- Typical RTE items:
- Delicatessen products (cheeses, luncheon meats)
- Fruits & vegetables (fresh-cut)
- Salads & salad ingredients
- Hotdogs
- Hard-boiled eggs that are peeled
Exercise – Which of the Following Are PHF?
- Fried rice ✓
- Sashimi ✓ (raw fish, high protein, ~neutral pH)
- Caramel cake ✗ (low water activity in frosting)
- Cut watermelon ✓
- Chicken pastel ✓
- Mashed potato ✓ (moist, neutral pH)
- Hawaiian pizza ✓ (meat & cheese toppings)
- Tofu ✓ (high protein, high a_w)
- Rib-eye steak ✓ (especially if undercooked)
- Goat cheese ✓
- Orange juice ✗ (pH < 4.6)
- Baked mussels ✓ (if held warm)
- Pancit palabok ✓ (moist noodles + proteins)
- Samgyeopsal ✓ (grilled meats held on table)
Biological Hazards – Foodborne Illnesses Caused by Bacteria
Bacterial Groups
- Spore-forming – can form resistant spores; survive cooking, dehydration, high salt; germinate under favorable conditions.
- Non-spore-forming – lack spores; generally destroyed by adequate cooking.
A. Spore-Forming Bacteria
| Bacterium | Oxygen Requirement | Illness Type | Key Symptoms (Onset) | High-Risk Foods | Core Prevention |
|---|---|---|---|---|---|
| Bacillus cereus | Facultative (w/ or w/o O$_2$) | Intoxication or toxin-mediated infection | • Diarrheal type: abdominal cramps (8–16 h) • Emetic type: vomiting ± cramps (30 min–6 h) | Diarrheal: meats, milk, veggies • Emetic: rice, starches, grains | Proper hot-holding; rapid cooling & reheating |
| Clostridium perfringens | Nearly anaerobic | Toxin-mediated infection | Intense abdominal pain, severe diarrhea (8–22 h) | Meats & gravies, stews, spice-rich dishes | Thorough cooking, rapid cooling, reheating to 165^\circ F |
| Clostridium botulinum | Strict anaerobe | Intoxication (neurotoxin) | Dizziness, double vision, dysphagia, respiratory paralysis (12–36 h) | Improperly canned foods, vacuum-packed items | Approved thermal processing, discard bulging cans, never use home-canned products |
B. Non-Spore-Forming Bacteria
| Bacterium | Special Growth Traits / Significance | Illness & Symptoms | Common Foods | Prevention |
|---|---|---|---|---|
| Campylobacter jejuni | Microaerophile (3–6 % O$_2$); leading cause of bacterial gastroenteritis | Watery/bloody diarrhea (2–5 d) | Raw poultry, unpasteurized milk | Avoid cross-contamination; cook poultry to 165^\circ F |
| Shiga-toxin–producing Escherichia coli (STEC) | e.g., E. coli O157:H7; low infectious dose | Hemorrhagic colitis → HUS, kidney failure (12–72 h) | Undercooked burgers, raw milk, cider, leafy greens | Ground-beef ≥ 155^\circ F; sanitation, handwashing |
| Listeria monocytogenes | Grows at <41^\circ F & high salt; dangerous for pregnant women | Flu-like → meningitis, fetal damage (1 d–3 wks) | RTE deli meats, soft cheeses, raw produce | Keep RTE foods ≤41^\circ F, FIFO rotation, cook thoroughly |
| Salmonella spp. | Facultative anaerobe in intestinal tracts | Nausea, fever, cramps, diarrhea (6–48 h) | Raw eggs, poultry, meat, milk | Cook poultry ≥ 165^\circ F; prevent cross-contamination |
| Shigella spp. | Human reservoir; produces shiga toxin (reverses water re-absorption) | Bacillary dysentery, severe diarrhea (1–7 d) | Hand-prepared salads, raw produce, RTE foods | Reinforce hand hygiene; exclude ill workers |
| Staphylococcus aureus | Produces heat-stable toxin on foods | Rapid nausea, vomiting, cramps (2–6 h) | Hand-contact foods, pastries, sliced meats | Good personal hygiene; keep foods ≤41^\circ F or ≥135^\circ F (cooking does NOT destroy toxin) |
| Vibrio spp. (cholerae, parahaemolyticus, vulnificus) | Halophilic; marine environments | Gastroenteritis, cholera-like dehydration (2–48 h) | Raw/undercooked shellfish | Source from approved waters; cook shellfish to 145^\circ F |
Biological Hazards – Foodborne Illnesses Caused by Viruses
- Viruses do not multiply in food, but food serves as vehicle; extremely small infectious dose; resistant to mild disinfectants.
| Virus | Primary Transmission | Key Clinical Features | Incubation | Implicated Foods/Media | Prevention |
|---|---|---|---|---|---|
| Hepatitis A | Fecal–oral, contaminated water, RTE foods | Jaundice, liver swelling, fatigue | 10–50 d | Hand-prepared foods, shellfish | Handwashing, exclude ill workers, vaccination |
| Hepatitis B | Blood & body fluids | Acute/chronic hepatitis, possible cirrhosis | 45–160 d | Not typically food; occupational relevance | Vaccination, safe practices |
| Hepatitis C | Bloodborne (IV drugs, transfusion) | Often asymptomatic → cirrhosis | 2 wks–6 m | Non-food route | No vaccine; medical controls |
| Norwalk / Norovirus | Person-to-person, water, shellfish | Projectile vomiting, diarrhea, cramps | 24–48 h | Raw oysters, salads, ice | Potable water, cook shellfish, sanitize surfaces |
| Rotavirus | Fecal–oral; infants & kids | Severe pediatric diarrhea, low fever | 1–3 d | Water, raw produce | Hygiene, immunization (Rotarix®, RotaTeq®) |
Biological Hazards – Foodborne Illnesses Caused by Parasites
| Parasite | Morphology / Alias | Symptoms (Onset) | Vehicles | Preventive Measures |
|---|---|---|---|---|
| Anisakis spp. | Nematode “herring/cod worm” (≈1.5 in) | Coughing, vomiting (1 h–2 wks) | Raw or undercooked marine fish | Cook fish to 145^\circ F; freeze −4 °F (−20 °C) ≥7 days |
| Cyclospora cayetanensis | Protozoan | Explosive watery diarrhea (≈1 wk) | Raspberries, basil, water | Reputable suppliers, washing |
| Cryptosporidium parvum | Protozoa in cow feces | Severe watery diarrhea (≈1 wk) | Contaminated water, ill handlers | Potable water, hygiene |
| Giardia lamblia | Protozoan “beaver fever” | Diarrhea (≈1 wk) | Untreated surface water | Boil or filter water, hygiene |
| Toxoplasma gondii | Protozoan in cats, livestock | Swollen nodes, eye/brain lesions (10–13 d) | Raw meats, produce | Cook meats, wash produce, control cats |
| Trichinella spiralis | Nematode | GI upset → muscle soreness (2–28 d) | Undercooked pork, wild game | Cook pork to 145^\circ F + 3 min rest; game 160 °F |
Chemical Hazards & Food Allergens
Naturally Occurring Chemicals
Food Allergens (immune hypersensitivity)
- “Big 8” (US)/“Big 9” (PH Draft): milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soy (Sesame sometimes added).
- Reactions: skin hives, oral swelling, GI distress, anaphylaxis; onset often minutes.
- Control: accurate labeling, segregation, dedicated utensils, informed staff.
Marine & Fungal Toxins
- Ciguatoxin: reef-associated finfish; vertigo, temperature reversal. Heat-stable.
- Scombrotoxin (Histamine): time-temperature abuse of tuna, mahi-mahi; rapid flushing, rash; prevent by chilling ≤41^\circ F.
- Shellfish Toxins (Paralytic, Neurotoxic, Amnesic): produced by dinoflagellates; neurologic numbness 10–60 min; buy from certified waters.
- Mycotoxins (Aflatoxin, Ochratoxin, etc.): molds on grains, nuts; acute hemorrhage or chronic carcinogenesis; keep products dry ≤0.70\ a_w.
Added / Man-Made Chemicals
- Cleaning & sanitizing agents (chlorine, quats) → use per label & properly store.
- Food additives (nitrites, sulfites) → comply with GMP & legal limits.
- Pesticide residues → wash/rinse, buy GAP-certified produce.
- Heavy metals from equipment (lead, copper, cadmium, galvanized containers) → use food-grade materials only.
Physical Hazards
- Foreign objects that may cause injury or illness.
- Common items: glass shards, metal shavings, staples, stones, bones, jewelry, hair, broken toothpicks, bandages.
- Controls: inspection of raw materials, protective coverings, metal detection, good maintenance, personal-hygiene rules (no jewelry).
Integrative Notes & Real-World Connections
- HACCP Principle 1 – Hazard Analysis relies on knowing all biological, chemical & physical hazards just outlined.
- Vulnerable groups (YOPI) suffer more severe outcomes; menu design & cooking standards must reflect this (e.g., no raw oysters in elder-care).
- Time–temperature abuse is the SINGLE most common root cause cited in epidemiological outbreak reports (ServSafe® data).
- Emerging pathogens (e.g., Listeria in ice cream, Cyclospora in imported berries) highlight global supply-chain complexity; necessitate supplier audits & traceability.
- Climate change may expand the habitat of Vibrio spp. → warmer seas → higher incidence of seafood-borne illness.
- Ethical duty: accurate allergen labeling protects consumer health & avoids legal liability (Phil. Food Safety Act penalties up to ₱ 500,000 & business closure).
Quick Reference – Critical Control Numbers
- TDZ: 41^\circ F to 140^\circ F ( 5^\circ C – 60^\circ C )
- Minimum internal cooking temps (US FDA Model Food Code):
- Poultry, stuffed foods: 165^\circ F ( <1 s )
- Ground meats: 155^\circ F (17 s)
- Fish, pork, beef steaks, eggs for immediate service: 145^\circ F (15 s)
- Plant foods hot-held: 135^\circ F
- Cooling guideline (2 + 4 rule): 135^\circ F → 70^\circ F within 2 h, then 70^\circ F → 41^\circ F within an additional 4 h.
Recommended Preventive Framework
- Purchasing – reputable, approved suppliers; certificates on shellfish.
- Receiving – inspect temperatures & packaging; reject cans with bulges.
- Storage – FIFO, label & date; separate raw from RTE; maintain ≤41^\circ F or ≥135^\circ F.
- Preparation – handwashing, avoid cross-contamination, calibrated thermometers.
- Cooking – reach regulatory internal temperatures; verify.
- Cooling & Reheating – use shallow pans, ice wands; reheat to 165^\circ F for 15 s.
- Service – hold hot foods ≥135^\circ F, cold foods ≤41^\circ F; 4-hour discard policy.
- Sanitation & Personal Hygiene – clean → rinse → sanitize (correct ppm); exclude ill workers ≥24 h after symptoms.
References (as provided)
- Bueno, D. (2014). Food Microbiology and Food Safety.
- National Restaurant Association. (2017). ServSafe Manager 7th ed.
- Somoray, A. (2016). Principles of Food Safety, Sanitation and Hygiene.
- Schmidt, R. H., & Rodrick, G. E. Food Safety Handbook. Wiley.
- InTechOpen (2020). “Food Safety – Problems and Solutions.”
- FRLA. ServSafe 6th ed.