Foodtech

Foodtech

1. Carbohyrates

   • The three types of carbohydrates
     • Sugar
       • Glucose, fructose (simple sugars) lactose, sucrose (double sugars)
       • 4 main types of sugars
         • Granulated, Caster, Brown and Icing
           • Most come from sugar cane. Sugar also naturally occurs in things like fruit and honey
       • Why is sugar used?
         • Makes things sweet, softens sharp flavours, Acts as a preservative eg jam, aerates when beaten with fat and lightens it eg in cakes, speeds up fermentation eg in bread, adds colour eg cakes, biscuits and pastries, can be heated and caramelise eg on top of desserts
       • Sugar substitutes
         • They are better for your health, contain fewer calories, good for those on a diet and diebetics, shouldn't be used in home baking as they do not have the same properties as cane sugar
     • Starch
       • Complex sugar- needs to be broken down before energy can be used. Good to eat a few hours before playing sport
       • Starch can alter the structure of foods and thicken foods
         • Bulking agent: Starch granules swell when a liquid is added so can provide the bulk of a product eg the flour makes up most of the volume in pasta
         • Gelling agent: When heat and moisture is added to the starch granules, At 80 degrees C starch particles break open and the mixture becomes thick and viscous, at 100 degrees C gelatinisation makes the thickened liquid form a gel and on cooling the gel solidifies and takes the form of the container its in
         • Thickening agent: Starch and liquid are mixed and form a suspension when heat is applied gelatinisation occurs which causes thickening
       • Modified starches (smart starches)
         • They are treated to react in certain conditions
           • Pre-gelatinised starch thickens instantly when mixed with hot water eg packet custard, instant noodles
         • Syneresis: When a protein coagulates, squeezing out the fat and water. It can be prevented by using modified starches as this allows reheating without syneresis, keeping the moisture in
       • Gluten helps bread dough stretch and rise and gives is elasticity (stretchiness)
     • Fibre
       • Bran, fruit, beans and brown bread contain alot of fibre

2. Proteins

   • Provide body with growth and repair
   • Protein is made of amino acids
     • Body breaks protein down into amino acids and uses these to build new proteins. Which your body then uses to make muscle etc
   • Meats
     • Beef, lamb and pork are called red meats they are a great source of protein but too much can cause heart diesese
       • Meat can be tenderised by partly breaking doiwn the fubres in the meat. You can do this by bashing it with a mallet, marinating it in something acidic or cooking it slowly eg in casseroles
       • Meat can dry out during cooking, to avoid this you can seal the outside of the meat by cooking at a high temperature for the first couple of minutes as this keeps the juices in
     • Chicken, turkey and duck are types of poultry and these are white meats
       • Poultry is a good source of protein and vitamin B and it is fairly low in saturated fat but it can be contaminated with the salmonella virus which can make you seriously ill.
   • Types of fish: Oily fish eg herring, mackerel, salmon and tuna, White fish eg cod, haddock, plaice and skate and shellfish eg crab, lobster and mussels
     • Fish is vert nutritious, it contains loads of vitamins and omega 3 oils which are dead good for you.
   • Eggs, Nutritional content: Protein about 13%, Fat which is mainly saturated about 10%, Vitamins A, B2 and D, Minerals, including iodine
     • Uses of eggs: Binding, Coating or Enrobing, Glazing, Aeration, Emulsification and Thcikening
       • Emulsification: Lecithin found in egg yolks keeps the emulsion stable eg in mayonnaise
       • Aeration traps air as the protein becomes stretched
       • Thickening due to coagulation. The egg white coagulates (becomes solid) at 60 degrees C and the egg yolk at 70 degrees C
       • Binding eg in burger as coagulation sticks the burgers together as they cook
     • Eggs may contain salmonella so it is important that the eggs are cooked thoroughly so that all bacteria gets destroyed. Pregnant women, babies, the elderly and frail people should be extra careful when eating eggs. MAnufacturers often use dried or pasteurised egg to be on the safe side eg in mayonnaise
     • Ways of cooking eggs
       • Boiled and poached re healthy as they are cooked using no fat
       • Scrambled eggs are healthy too and if you do them in a microwave you dont need any fat
       • Fried eggs can absorb alot of fat from the oil so it is best to use unsaturated fat and drain off as much ail as possible