Concetti Chiave
- Bacteria are microorganisms that include helpful, spoilage, and pathogenic types, each playing different roles in food and health.
- Pathogenic bacteria are responsible for food poisoning and can be found in various sources like raw food, pests, and poor hygiene.
- Cooking can destroy bacteria, but some form protective spores that allow them to survive harsh conditions.
- Bacteria need food, moisture, warmth, and time to multiply to dangerous levels, making hygiene crucial in food handling.
- Food contamination can be physical, chemical, or microbial, with contaminants coming from various sources like equipment, animals, and poor hygiene.
Bacteria and food poisoning
Bacteria are single celled micro-organism, invisible to human eye and living all around the natural world. There are helpful bacteria, spoilage bacteria and photogenic bacteria.
Helpful bacteria help us to digest food, to make food such as yogurt and cheese and make crops.
Spoilage bacteria make food perish.
Pathogenic bacteria cause illness and responsible for food poisoning and food borne diseases. They can be found in raw food, pests and pets, people, air and dust, dirt and food waste.
Cooking usually destroys them, but when they form spores, that is a protective coating, bacteria can survive even harsh conditions.
Bacteria can move, but they cannot travel on their own.
To multiply to dangerous levels bacteria need particular conditions such as food, moisture, warmth and time.
Food contamination refers to the presence in food of harmful chemicals and microorganisms which can cause consumer illness.
Contaminants can be: physical, chemical and microbial.
Examples of physical contaminants are: stones, fruit leaves, shell fragments, fish scales, poultry bone fragments, jewellery, hair, fingernails, insects, dust, dirt.
Examples of chemical contaminants are: clearing chemicals, agricultural chemicals, pesticides and pest bait.
Example of microbial contaminants are: cuts, boils of the skin, poor personal hygiene on hands, ears, hair, insects, mice, dogs, cats, fur feathers, untreated sources of drinking water, unwashed fruit and vegetables.
Contamination can be:
DIRECT, when a raw food touches a high risk food;
INDIRECT, when a liquid or juice from a raw food drip onto high risk food;
CROSS, when bacteria are carried, for instance by hands or utensils, from a raw food to a high risk food.