Food can make you ill for many reasons. To work safely you need to recognise the hazards and know how they reach the plate.
The three types of hazard
- Biological. Bacteria, viruses, moulds and parasites. They are the most frequent cause of food poisoning.
- Chemical. Detergents, disinfectants, pesticides, residues of substances used at work, and also undeclared allergens.
- Physical. Foreign bodies such as glass, splinters, metal fragments, pieces of packaging, hair, jewellery, plasters.
The most important micro-organisms
Bacteria multiply very well when they find food, moisture, time and favourable temperatures. Some examples:
- Salmonella: often found in eggs, poultry and raw meat.
- Listeria monocytogenes: survives the cold of the fridge. It is a particular concern for pregnant women, older people and vulnerable people. It can be found in ready-to-eat products, soft cheeses and sliced cured meats.
- Staphylococcus aureus: lives on people's skin and in their noses. It can produce toxins that cooking does not destroy.
- Norovirus: passes from a sick person to food, often via the hands.
- Toxin-producing Escherichia coli and Campylobacter: linked to raw meat, raw milk and unsafe water.
Some bacteria form spores or toxins that withstand heat. That is why poor preparation cannot be put right by "heating it more".
How contamination arrives
- From people: dirty hands, coughs and sneezes, gut illnesses, infected wounds.
- From raw materials: meat, poultry, eggs and vegetables with soil may already be contaminated.
- From the environment: dirty surfaces, waste, unsuitable water, insects and rodents.
- From wrong use of equipment: knives, chopping boards, cloths and gloves used first on raw food and then on ready-to-eat food.
Cross-contamination
This is the passage of microbes (or allergens) from one food to another. The typical case: you cut raw chicken and then, with the same board, the salad. The chicken is cooked, the salad is not.
How to prevent it:
- keep raw and cooked apart, in the fridge and on the worktop;
- keep raw food at the bottom and ready-to-eat food above;
- use separate equipment (or equipment well washed and disinfected between uses);
- wash your hands after touching raw food;
- cover food and store it in closed containers.
What microbes need to grow
Food rich in protein or water, time and temperature. You can act mainly on the last two: keep food out of the right temperature for as short a time as possible and respect the cold chain and the hot chain (lesson 4).
Foodborne illnesses
Typical symptoms: nausea, vomiting, diarrhoea, fever, abdominal pain. Anyone with these symptoms must not work with food (lesson 3). A single sick worker can infect many people.
Receiving and checking goods
Regulation 852/2004 (Annex II, Chapter IX) says that the FBO must not accept raw materials or ingredients that it knows are contaminated in a way that will not be made safe by normal treatment. On delivery, check:
- the temperature of chilled and frozen products;
- that packaging is intact and clean;
- the label and the expiry date;
- the appearance, smell and cleanliness of the delivery vehicle.
If something is wrong, do not accept the goods, or set them apart and tell the person in charge.
Remember
- Hazards are biological, chemical and physical.
- Bacteria grow with food, moisture, time and temperature.
- Cross-contamination is avoided by keeping raw and ready-to-eat food apart.
- A sick worker must not handle food.