CAUSES AND SOURCES OF FOOD CONTAMINATION AND POISONING

CONTENT

1. Causes of Food Contamination and Poisoning
2. Sources of Food Contamination and Poisoning
3. Sensory Signs of Spoilage and Causative Micro-organisms

Causes of Food Contamination and Poisoning

The causes of food contamination and poisoning include:

1. Contamination of food by micro-organisms e.g. bacteria (Escherichia coli, salmonella), virus (noro-virus, rota- virus, sapo-virus etc.)
2. Parasites: they derive nourishment from their host, e.g. round worms, tape worms etc.
3. Toxins and contaminants: some bacteria produce toxin or poison outside their cells when they are growing and multiplying in food, these toxin are known as exotoxins; are poisonous chemicals are less easily destroyed by heating than the bacteria from which they come. Heating of food may kill bacteria, but the toxins may still survive an still cause food poison when the food is eaten.
4. Yeast: this is responsible for decomposition of food with high sugar content.
5. Allergens: food allergens are an abnormal response to food triggered by one’s body immune system.

Sources of Food Contamination and Poisoning

The major sources of food poisoning and contamination are:

1. Air
2. Dust
3. Sewage
4. Rodents
5. Flies
6. Dirty equipment
7. Insects
8. person
   

Sensory Signs of Spoilage and Causative Micro-organisms

Meaning of Food Spoilage

This is undesirable changes taking place in the food which eventually leads to its rejection.