Food borne illness is when someone gets sick (diarrhea, stomach pains, vomiting) from eating contaminated food. Mostly food borne illness is caused by harmful bacteria that gets into food. The micro-organism itself makes you sick or it produces a toxin that makes you sick. Yet, proper handling of food and good hygiene can prevent it. KEEP FOOD SAFE!
Invisible micro-organisms
Micro-organisms are very small (living) organisms. They are not visible to the naked eye. You need a microscope to see them. The study of micro-organisms is called microbiology.
Many different types
- There are many different types of micro-organisms.
- Bacteria are just one type, alongside viruses, fungi and protozoa
Not all are bad. Micro-organisms can be found everywhere. Some are useful, e.g. Yeast (to produce butter, yogurt, bread), Mould (in cheese), bacteria (in dairy, sausages). Some are vital (digestion). Few can cause illness- pathogens (e.g. Salmonella, Listeria) OR spoilers (Moulds on bread, Lactobacilli in milk).
SO KEEP THE BAD ONES OUT!
Don’t help them! Micro-organisms don’t have legs. They need help to get from place to place. They can get into food via
- people (sneezing, coughing, or via clothes or dirty hands!)
- raw food and contaminated water
- insects and pests
- dirty equipment, tools and utensils
- dust and soil
MAKE SURE YOU DON’T HELP THEM END UP IN THE FOOD!
Bacteria grow rapidly. Depending on conditions, bacteria can grow and multiply very rapidly. They can double their numbers every 20 minutes:
| Time | No of bacteria |
|---|---|
| 0 | 1 |
| 20 mins | 2 |
| 2 hours | 64 |
| 6 hours | 262144 |
| 8 hours | 16777216 |
| 16 hours | 35184373088832 |
Conditions for growth
Bacteria are like people – they have certain needs to keep them alive and grow.
- Food – no food, no bacteria
- Acidity (pH) – the more acidic, the less bacteria
- Temperature – they like it from 7 to 65C (45-150F)
- Time – more time, more bacteria
- Oxygen – no oxygen, no life
- Moisture – less water, less bacteria
Temperature danger zone
Germs multiply rapidly at temperatures between 7 and 65C (45-150F). That’s the temperature danger zone.
- Cold does not kill germs – it only slows growth
- Heat (>75C/165F) kills most germs – so make sure food is cooked well and held at proper temperatures
- The longer the cooking time, the more die – cook food for 2 minutes at least
So: keep clean & prevent:
- Contamination – harmful substances getting into food causing illness or injury.
- Cross-contamination – contaminants being carried from one food or utensil to another by dirty hands, utensils, gloves, equipment or food
- KEEP YOURSELF CLEAN!
- KEEP YOUR WORK AREA CLEAN!
- KEEP THE FOOD CLEAN!
And: Avoid the danger zone
- Cook food WELL!
- Keep hot food HOT!
- Keep cold food COLD!
- Keep frozen food FROZEN!
- or best: DON’T KEEP IT AT ALL!
- CONTROL TEMPERATURE AND TIME!
Cleaning and disinfection
Cleaning removes micro-organisms; disinfection kills them. The objective is to reduce their numbers to safe, harmless levels. Clean all areas, surfaces and equipment
- as you go
- between and after preparing raw and ready to eat food or high risk foods
- after final use for the day
Pay special attention to food contact points (cutting boards, containers, utensils) and hand contact points (door handles, taps) – these items should be disinfected frequently.
Watch for the tough guys
Some bacteria are less sensitive to disinfectants than others, or produce a toxin or form spores that survive heat, drought, most chemical disinfectants, and make you sick. Only good cleaning and strict hygiene helps.
Viruses are tiny micro-organisms that use other cells to multiply by injecting their genetic material. Viruses are very much harder to kill by disinfectants than bacteria. They can be spread by coughing and sneezing, so good personal hygiene and social distancing is crucial.
Fungi causes food spoilage. Fungi are present in the air, on surfaces, and on mouldy food. So foods should always be covered and mouldy food must be discarded.
