Food Decay and Preservation
Bacteria and fungi are the main groups of decomposer organisms. Food decay is also known as food spoilage.
Bacteria and fungi need Food , Warmth and Moisture to grow.
There are several ways to stop or slow down the decay of foods. This is known as Food Preservation.
Food preservation methods
Bacteria cannot reproduce at low temperatures.
Bacteria and fungi need warmth to grow. In low temperatures they stop growing.
Following is the list of food preserved by freezing;
- Fresh foods
- Cooked foods
Removing water prevents the microorganisms from growing, or digesting the food.
A look at the grade 2 lesson
Grade 2 Science(NSO) : Food
Food can be divided into three types
Energy giving food
Give us energy to work. They contain carbohydrate and fats.
They are found in foods like rice, pasta, cassava, yam etc. when starchy foods are eaten and digested, simple sugars like glucose are obtained. It is this glucose that the body uses for energy.
There are two major types of carbohydrates:
1. Simple carbohydrates (Sugar)
- White sugar you would find in a sugar bowl
Cooking of food
Cooking improves the flavor of food and also makes the food easier to chew and more digestible. Micro oirganisms present in the food are killed during cooking which makes the food safer to consume. Various methods of cooking are listed below :
Involves cooking the food at the boiling temperature of water ie 100 degree centigrade.
Example : Eggs , potatoes etc