SCIENTIFIC STUDY OF FOOD

DEFINITION OF FOOD NUTRIENTS

Food nutrients are the chemical substances in the food we eat. The various food nutrients differ from each other in their physical properties and chemical properties.

TYPES OF FOOD NUTRIENTS AND THEIR CHARACTERISTICS

PROTEINS

Proteins are bodybuilders. They are important for building and repairing body tissues. Sources include; meat, fish, eggs, poultry, milk, beans etc.

CHARACTERISTICS OF PROTEIN

1. Proteins are made up of carbon, hydrogen and nitrogen. There are elements.
2. The elements arranged themselves in different combinations to from amino acids.
3. The amino acids then form the proteins.
4. The final products of protein digestion are the amino acids
5. Proteins are digested by enzymes called protease.
6. Most proteins are insoluble in water.

CARBOHYDRATES

Carbohydrates are energy foods. They include sugars, starches and cellulose. Food sources included yam, rice, maize, cassava etc.

CHARCTERISTICS OF CARBOHYDRATES

1. The elements that make up carbohydrates are carbon, hydrogen and oxygen.
2. These elements combine in different ways to form.
3. Simple sugars e.g. glucose, fructose etc.
4. Complex sugars e.g. lactose
5. Starches e.g. yam, cassava e.tc.
6. Cellulose, this is found in some vegetables
7. All sugars are sweet but they vary in sweetness.

FAT AND OILS

Fats and oils are energy gives, like the carbohydrates, sources of fats and oils include palm oils, groundnut oil, fatty meat, egg yoke, butter, margarines’ etc.

CHARACTERISTICS OF FAT AND OILS

1. They contain high proportions of carbon and hydrogen but very little oxygen.
2. They are bad conductors of heat.
3. Fats and oils are insoluble in water.
4. Fats are solid at room temperature, oils are liquid.
5. VITAMINS:

Vitamins A&D

1. These are fat soluble vitamins
2. They are not dissolved in water
3. They are not destroyed by ordinary cooking
4. They are destroyed when the fat that contains them goes spoilt.

Vitamin B & C

1. It is water – soluble i.e. it dissolves in water
2. Food sources should be cooked in small quantity of water using quick cooking method.
3. Rich vitamin C food such as oranges are often eaten raw.
4. Fast method of cooking should be used, over – cooking can lead to loss of vitamin.

MINERIALS

1. Dry heat has little effect upon minerals in food
2. Moist heat may result in the loss of some of the soluble minerals such as sodium, potassium and magnesium salts.

See also

HEALTHY FEEDING AND EATING PRACTICES

GOOD POSTURE AND EXERCISE

THE TEETH, HANDS AND FEET

STRUCTURE OF THE SKIN

NOSE AND EAR