Causes And Sources Of Food Contamination And Poisoning JSS3 Home Economics Lesson Note

CAUSES AND SOURCES OF FOOD CONTAMINATION AND POISONING

The causes of food contamination and poisoning include:

Contamination of food by micro-organisms e.g. bacteria (Escherichia coli, salmonella), viruses (norovirus, rotavirus, sapo-virus, etc.)

Parasites: they derive nourishment from their host, e.g. roundworms, tapeworms, etc.

Toxins and contaminants: some bacteria produce toxins or poison outside their cells when they are growing and multiplying in food, these toxins are known as exotoxins; are poisonous chemicals that are less easily destroyed by heating than the bacteria from which they come. The heating of food may kill bacteria, but the toxins may still survive and still cause food poison when the food is eaten.

Yeast: this is responsible for the decomposition of food with high sugar content.

Allergens: food allergens are abnormal responses to food triggered by one’s body’s immune system.

Sources of Food Contamination and Poisoning

The major sources of food poisoning and contamination are:

 Air

Dust

Sewage

Rodents

Flies

Dirty equipment

Insects

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. It can also be defined as the deterioration of the physical and chemical properties of food, making it unfit for consumption.

The signs of food spoilage include the following:

Unpleasant odour

Unpleasant taste

Unpleasant texture

Unpleasant color

 EVALUATION

State four causes of food poisoning

Mention five sources of food poisoning and contamination