Food technology – Summary NUTRITION
Protein
-Body is made up of protein- every cell has protein in it
Protein:
1. Makes up structure of body 2. New protein is needed for growth and repairing body cells when cells are old or damaged 3. Inside body- proteins used as messengers and workers in body system 4. Regulates the amount of fluid in body.
Can be used for fuel if other sources run out- 17 kilojoules of energy per gram
Amino acids- proteins are composed of 22 different amino acids. 8 are essential- body cannot make them. Others can be made in the body from ingested amino acids
Complete and incomplete proteins:
COMPLETE- animal proteins (meat, fish, poultry, milk, cheese, and eggs) Complete proteins contain adequate amounts of all essential amino acids.
INCOMPLETE- Vegetable proteins (grains, legumes, nuts, seeds, and other vegetables) are incomplete proteins because they are missing, or do not have enough of, one or more of the essential amino acids. Incomplete proteins can combine to form complete proteins. Eg Mexican beans with corn tortillas
Deficient in protein: - swelling of the tissue - slow healing - stunt growth -impaired digestion

Lipids
Lipid or ‘fat cell’ in your body- important store of energy
Lipids:
- carry, in your blood some of the vitamins not soluble in water (Vitamins A,D, E and K) - Keep skin and hair soft and smooth * Provides essential fatty acids
Provides 37 kilojoules per gram
Three types: 1. Unsaturated fats- good for heart. E.g plant foods and fish 2. Saturated fats- can raise blood cholesterol levels and increase risk of heart disease. E.g meat, butter, cheese, commercial baked goods 3. Trans fats- raise cholesterol and increase the risk of heart disease. Eg snack food, fried food, baked goods.
Sources: 1. Animals sources -meat - dairy foods - oily fish 2. Plant sources - avocado - olives - coconut

Carbohydrates
Carbohydrate is a nutrient made up of carbon, hydrogen and oxygen. It results from photosynthesis in plants.
Three classes of CHO’s:
1. Monosaccharides- Simplest form of CHO’s. Three forms: 1.Glucose (ripe fruits, honey, some veg) 2. Fructose (fruits and honey) 3. Galactose- formed during the digestion of lactose (milk sugar)
2. Disaccharides- Contains two molecules of monosaccharides and include:
1. Sucrose (cane sugar, fruits, some veg)
2. Lactose (found in milk)
3. Maltose (found in malt sugar)
FOODS RICH IN SUGARS:
-Honey
-Orange juice
-lollies
-Dried fruit
FOODS RICH IN SUGARS:
-Honey
-Orange juice
-lollies
-Dried fruit
3. Polysaccharides- made up of many molecules of monosaccharides
FOODS RICH IN STARCH:
- potato
-Wholemeal bread
-Cooked rice
-corn
CARBOHYDRATES are the body’s preferred source of energy.

During digestion- starches and sugars break down into glucose.

CHO’s are stored as glycogen in the liver, when required, is released as glucose to maintain a steady blood glucose level.
1 gram of CHO= 16 kilojoules
Vitamins
Vitamins are critical for the functioning of the body and are involved in many metabolic processes, regulating blood cells, formation of hormones. They do not provide energy-but required for the release of energy from carbohydrates, protein and fats. Water-soluble vitamins are not stored in your body and need to be continually replenished from your diet.
Types of WATER SOLUBLE vitamins: (dissolve in water)
THIAMIN: it releases energy from carbohydrates and lipids. Found in all plants and animals. Particularly meat. Highly processed foods are generally lower in thiamin.
VITAMIN C: involved in formation of collagen, which helps to maintain strength of cell walls and of body tissues like skin. Vitamin deficiency causes a disease called scurvy. Plant foods- main source of vitamin C.