Food Commodities

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Food Commodities
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CONTENTS

1. What are Food Commodities
2. Rice, Wheat and Cereals
3. Meat Poultry
4. Seafood
5. Eggs
6. Cheese Milk
7. Legumes, Vegetables and Fruit
8. Summary

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1. What are food commodities?
Products or raw materials that can be bought or
sold.
They are wheat, rice cereals meat
poultry seafood eggs cheese
milk legumes, vegetables fruit
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2. WHEAT, RICE CEREALS
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2. WHEAT, RICE CEREALS
Wheat

• Main cereal food in many Western countries.
• Grown in regions such as USA, Canada, Europe,
  Russia, Egypt and India.

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2. WHEAT, RICE CEREALS

• Structure of Wheat
• Composed of 3 parts
• Bran
• Endosperm
• Germ

Source http//www.pechsiam.com/allabout.htm, 2006
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2. WHEAT, RICE CEREALS

• Types of Flour

Types Uses
Soft, weak flour, low in protein For making cookies, cakes, crackers pastries
Hard, strong flour, high in protein (made from hard red winter wheat) For making pan breads, pizza crusts rolls
Hard, strong flour, high in protein (made from hard red spring wheat) Mainly for making breads
White wheat flour (made from hard white wheat) For making the same products as soft hard red wheat
Durum flour (made from durum wheat) course ground endosperm (semolina) for production of pastas durum flour for making American noodles some types of pastas
Wholegrain wholemeal flour For making breads muffins
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2. WHEAT, RICE CEREALS
Nutrients in Wheat

• Carbohydrates
• Proteins
• Fats
• B-vitamins
• Vitamin E

• Iron
• Phosphorus
• Calcium
• Fibre

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2. WHEAT, RICE CEREALS
Using Wheat in Cooking

• When heat is applied in a baked product, the
  proteins coagulate to give final structure of the
  product.
• The starch granules absorb water, swell burst,
  resulting in a moist product.
• Commonly used as the main ingredient for cakes,
  biscuits, pastries, bread snack items.

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2. WHEAT, RICE CEREALS
Rice

• Staple food in several Asian countries,
  particularly China, India, Japan Korea.
• Structure is similar to wheat.
• Can be short-grained (glutinous when cooked) or
  long-grained (fluffy when cooked)

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2. WHEAT, RICE CEREALS
Types of Rice

• Polished rice

• Unpolished rice

• Glutinous rice

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2. WHEAT, RICE CEREALS
Nutrients in Rice

• Carbohydrates
• Proteins
• Fats
• B-vitamins

• Iron
• Phosphorus
• Magnesium

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2. WHEAT, RICE CEREALS
Using Rice in Cooking

• When cooked in water, the grains absorb water
  swell.
• If correct amount of water is used light,
  fluffy glutinous rice is produced
• If too much water is used rice turns mushy
• Consumed as cooked plain rice or made into rice
  products such as dumplings, porridge, rice
  crispes or longtong.

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2. WHEAT, RICE CEREALS
Cereals

• Seed grains of cultivated grasses.
• Most common staple food in most countries as they
  are relatively inexpensive easy to grow.

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2. WHEAT, RICE CEREALS

• Types of Cereals

Types Nutrients Uses
Maize (corn) Carbohydrates, proteins, fats, fibre, iron and vitamins especially B1, B2 B3 Yellow variety contains carotene that can be converted into vitamin A by the body Eaten as corn-on-the-cob Used in soups cereals Crushed corn grain for making tortilla Fine corn flour thickening agent for gravies soups Used in cakes, biscuits blancmange
Oat Higher fat, protein soluble dietary fibre content than other cereals For making oat porridge, muesli oat brans
Barley Similar to other cereals Used in barley drinks, soups and local desserts Added to cattle feed used in the whisky-making industry
Rye Similar to other cereals For making breads, biscuits pancakes
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3. Meat Poultry
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3. MEAT POULTRY
Meat

• Refers to the flesh of animals, which is made up
  of muscles fats.
• Animals are reared on farms for their meat.

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3. MEAT POULTRY
Types of Meat

• Beef (from cattle)
• Mutton (from goat sheep)
• Pork (from pig)
• Veal (from calf)
• Venison (from deer)

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3. MEAT POULTRY
Structure of Meat

• Composed of 2 main proteins
• Myosin
• Actin
• Click here to find out how myosin and actin look
  like.
• Fibres are held together in bundles by connective
  tissue, which is made up if 2 proteins
• Collagen
• Elastin
• Small amount of fats in between muscle fibre of
  lean meat are known as marbling fats
  contributes to flavour, moisture texture.

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3. MEAT POULTRY
Structure of Meat
Legend
Actin
Myosin
Back
Source http//www.exploratorium.edu/cooking/meat/
INT-what-is-meat.html, 2006
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3. MEAT POULTRY
Nutrients in Meat

• Proteins
• Fats
• Cholesterol
• Vitamin D
• Vitamins, especially B1, B2 B3

• Phosphorus
• Sulphur
• Iron
• Water

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3. MEAT POULTRY
Using Meat in Cooking

• When cooked using dry heat such as roasting,
  soluble proteins coagulate resulting in some
  shrinkage.
• Colour of meat changes from red to brown.
• During moist-heat cooking such as braising,
  insoluble proteins are slowly converted into
  soluble gelatine. Soluble vitamins minerals are
  passed into cooking water. Some flavouring matter
  leave the meat, making the meat less tasty.

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3. MEAT POULTRY
Before cooking
After cooking
Beef muscle fibers with blow-up of a coiled
protein, before cooking
An uncoiled, or denatured, protein, after cooking
Sourcehttp//www.exploratorium.edu/cooking/meat/I
NT-what-is-meat.html, 2006
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3. MEAT POULTRY
Poultry

• Domesticated birds such as
• Chickens
• Ducks
• Geese
• Turkeys

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3. MEAT POULTRY
Nutrients in Poultry

• Proteins
• Fats
• Cholesterol
• Vitamin B-group

• Phosphorus
• Iron
• Water

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3. MEAT POULTRY
Using Poultry in Cooking

• Method of cooking depends on age of the bird.
• Young bird is tender has very little fat best
  fried, grilled or roasted whole.
• Over-roasting tends to toughen the meat make
  the flesh dry.
• Older bird is tougher as it has more connective
  tissue in the muscles suitable for simmering,
  boiling steaming.
• Can be used to make stews, soups, pies burgers.
  

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3. MEAT POULTRY
Offal

• Edible internal parts of the animals such as
• Liver
• Heart
• Kidneys
• Tripe (stomach)
• Tongue
• Brain
• Intestines

Source http//www.halalmeat.com.au/offal.html,
2006
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3. MEAT POULTRY
Nutrients in Offal

• Proteins (high)
• Fats
• Cholesterol (high)

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3. MEAT POULTRY
Using Offal in Cooking

• Requires thorough cleaning to remove any
  unpleasant smell.
• Liver kidneys are best sliced thinly fried.
• Tripe intestines are usually boiled or made
  into a stew.

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4. Seafood
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4. SEAFOOD
Seafood

• Comprises
• Fish
• Shellfish

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4. SEAFOOD
Types of Fish

• White fish
• Pomfret
• Red snapper
• Threadfin

• Oily fish
• Mackerel
• Shad

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4. SEAFOOD
Types of Shellfish

• Molluscs
• Cockles
• Clams
• Oysters

• Crustaceans
• Crabs
• Prawns
• Lobsters

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4. SEAFOOD
Structure of Seafood

• Has less connective tissue than meat no
  elastin.
• Muscle fibres are shorter than those of meat
  easier to cook more digestible than meat.
• Shellfish is tougher more chewy less
  digestible than white oily fish.

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4. SEAFOOD
Nutrients in Seafood

• Potassium
• Sodium
• Phosphorus
• Water

• Proteins
• Cholesterol
• Calcium
• Iron
• Iodine
• Unsaturated fats (little or no)
• Vitamin A, D B-group

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4. SEAFOOD
Using Seafood in Cooking

• In dry-heat cooking such as frying, soluble
  proteins coagulate, causing shrinkages. As water
  evaporated from the surface of the seafood,
  deposits of flavouring matter minerals are left
  behind makes fried fish prawns tasty.
• In moist-heat cooking such as boiling,
  water-soluble nutrients flavouring matter may
  be lost from the seafood seafood may taste
  bland.
• Fish can be grilled, baked, pan-fried or steamed.
• Used as fish curry, fried fish, fish cakes and
  fishballs. Raw fish (sashimi) is a Japanese
  delicacy.
• Shellfish can be fried, frilled, steamed or
  boiled. Molluscs must be properly cooked as they
  tend to harbour harmful bacteria.

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5. Eggs
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5. EGGS
Eggs

• Economical food source that can be used in a
  variety of ways.
• One of the most common breakfast foods.

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5. EGGS
Types of Eggs

• Eggs of
• Chicken
• Ducks
• Geese
• quails

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5. EGGS

• Structure of Eggs
• Composed of 3 main parts
• Eggshell
• Egg white
• Egg yolk

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5. EGGS
Source http//www.eggs.ab.ca/about/egggrades.htm,
2006
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5. EGGS
Nutrients in Eggs

• Sodium
• Chlorine
• Sulphur
• Water

• Proteins
• Fats
• Cholesterol
• Calcium
• Iron
• Potassium
• Vitamin A, B-group, D, E K

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5. EGGS
Using Eggs in Cooking

• Heat causes proteins to coagulate
• egg white turns solid opaque
• egg yolk turns solid, dry and powdery
• Can be fried, boiled, scrambled, poached, steamed
  or made into omelettes, soufflés custards.

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EGGS
Using Eggs in Cooking

• Have the following uses in cooking
• As a main protein food such as omelette
• For thickening soups, sauces, puddings custards
• As a rising agent in cake-making
• For trapping air to make food light. Eg chiffon
  cakes
• As an emulsifier. Eg mayonnaise
• For glazing pastries pies to give them a shiny
  look
• For coating food. Eg fish cutlets

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6. Cheese Milk
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6. CHEESE MILK
Milk

• Usually obtained from cows.
• Milk of other animals such as goats mares is
  also consumed by people.
• Milk its products such as butter, cream
  cheese are known as dairy foods.

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6. CHEESE MILK

• Types of Milk

Types Properties
Untreated mlik Milk that has not gone through any kind of heat treatment bottled in the farm
Pasteurised milk Milk that has been given mild heat treatment (72C for 15 secs) to destroy most disease-carrying germs
Homogenised milk Pasteurised milk processed to disperse the fat globules distribute them evenly throughout the milk
Sterilised milk Homogenised milk heated to a high temperature (113C for 15-40 min) in a vacuum-sealed container
Ultra-high temperature milk (UHT milk) Homogenised milk heated to a high temperature of 132C for not more than 1 sec packaged in sealed cartons can be kept for months without refrigeration
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6. CHEESE MILK

• Types of Milk

Types Properties
Evaporated milk Milk from which some water has been removed by evaporation contains 25 less water than fresh milk sterilised at 115.5C for 20 min
Condensed milk Milk from which some water has been removed by evaporation sweetened with sugar
Powdered milk Milk from which all water has been removed in powder form
Skimmed milk Milk with fats skimmed off
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6. CHEESE MILK
Nutrients in Milk

• Sodium
• Chlorine
• Phosphorus
• Water

• Carbohydrates
• Proteins
• Fats
• Cholesterol
• Calcium
• Potassium
• Vitamin A, B1, B2, B3, C D

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6. CHEESE MILK
Using Milk in Cooking

• When milk is boiled, proteins coagulate form a
  layer on the surface. As the boiling continues,
  hot air steam get trapped under this layer
  causes the milk to overflow from its container.
• Can be consumed on its own.
• Used in beverages such as tea, coffee, cocoa
  milkshake.
• Used in many parts of the world to make desserts.
• Also processed to produce dairy products such as
  cheese, cream butter.

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6. CHEESE MILK
Cheese

• Concentrated form of milk
• A means of preserving the nutritive value of milk
  most important milk product

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6. CHEESE MILK
Types of Cheese

• Very hard cheese
• Parmesan cheese
• Hard cheese
• Cheddar cheese

• Soft cheese
• Cream cheese
• Processed cheese
• Cottage cheese

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6. CHEESE MILK
Nutrients in Cheese

• Sodium
• Chlorine
• Phosphorus
• Water

• Proteins
• Fats
• Cholesterol
• Calcium
• Potassium
• Vitamin A, B1, B2, B3, C D

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6. CHEESE MILK
Using Cheese in Cooking

• When cheese is heated, the fat melts separates,
  the cheese becomes soft.
• On further heating, the proteins over-coagulate
  become stringy tough.
• Used in macaroni cheese, cheese biscuits,
  cheesecake, cheese scones cheese sauce.
• Also used as topping for food items like pizza,
  lasagne and salads.

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7. Legumes, Vegetables Fruit
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7. LEGUMES, VEGETABLES FRUIT
Legumes Pulses

• Plants with seeds that grow in special fruits
  known as pods
• Legumes pods
• Pulses edible dried seeds within the pods

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7. LEGUMES, VEGETABLES FRUIT
Types of Legumes Pulses

• Legumes
• French beans
• Long beans

• Pulses
• Peas
• Lentils
• Peanuts

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7. LEGUMES, VEGETABLES FRUIT
Nutrients in Legumes Pulses

• Iron
• Calcium
• Potassium

• Carbohydrates
• Proteins
• Fats
• Fibre
• Vitamin B-group

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7. LEGUMES, VEGETABLES FRUIT
Using Legumes Pulses in Cooking

• Pulses need to be soaked in water prior to
  cooking causes them to swell soften gt easier
  to cook, usually by boiling or simmering.
• Used in soups, stews, salads dhal curries.
• Used to make tofu, soya milk, tempeh, soya sauce
  salted soya beans.
• Textured soya protein is known as textured
  vegetable protein.

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7. LEGUMES, VEGETABLES FRUIT
Vegetables

• Plants or plant parts that are used as food

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7. LEGUMES, VEGETABLES FRUIT
Types of Vegetables
Types Examples Nutrients
Leaves Lettuce, spinach, cabbage, kale, mustard greens Vitamin A, C, E K, calcium, iron, sulphur, phosphorus
Stems Celery, asparagus Vitamin A, B1, B2, B6, folic acid, potassium
Tubers Potato, sweet potato, yam, tapioca, water chestnut Carbohydrates, vitamin C
Roots Carrot, turnip Carbohydrates, vitamin A, B6 C, calcium
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7. LEGUMES, VEGETABLES FRUIT
Types of Vegetables
Types Examples Nutrients
Bulbs Onion, garlic Carbohydrates, vitamin A, B6 C, calcium
Flowers Cauliflower, broccoli Vitamin A, B-group, C E, folic acid, potassium, phosphorus, magnesium
Fruits Tomato, cucumber, eggplant Vitamin A, B-group C, potassium
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7. LEGUMES, VEGETABLES FRUIT
Using Vegetables in Cooking

• Vegetables are cooked to make them more
  digestible.
• During cooking, volume of vegetables is reduced
  as the fibres are soften. Heat also causes starch
  grains to swell gelatinise.
• When green vegetables are cooked, they initially
  appear to become greener due to chlorophyll
  pigments. Upon long period of cooking, the
  pigments break downs to appear yellowish.
• Leafy vegetables may be stir fried or boiled
  eaten with the liquid.
• Root vegetables may be baked, roasted, braised or
  pressured-cooked.
• Soft vegetables such as tomatoes fresh
  mushrooms may be grilled.

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7. LEGUMES, VEGETABLES FRUIT
Fruit

• Prized for its refreshing flavour sweetness
• Most fruit, when ripe, can be eaten at any time
  or after a meal as a dessert.
• Others are better after they are cooked.

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7. LEGUMES, VEGETABLES FRUIT
Types of Fruit
Types Examples
Stone fruit Peach, cherry, plum, apricot
Fleshy fruit Apple, pear, pineapple, papaya, banana, melon
Berry fruit Strawberry, blackcurrant, raspberry, gooseberry
Citrus fruit Orange, lemon, tangerine, lime
Dried fruit Sultana, raisin, date, prune, currant
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7. LEGUMES, VEGETABLES FRUIT
Nutrients in Fruit

• Potassium
• Phosphorus
• Manganese
• Water

• Carbohydrates
• Fibre
• Calcium
• Iron
• Vitamin A, B-group C

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7. LEGUMES, VEGETABLES FRUIT
Using Fruit in Cooking

• Fruit is usually eaten raw, either on its own or
  in salads.
• May also be cooked by stewing, baking, frying
  boiling.
• Can be used in pie fillings, pies, puddings,
  fritters jams. May be chopped or pureed before
  use.
• During cooking, pectin in acidic fruit dissolves
  in the warm acid condition, softening the
  tissues. Cellulose walls are also softened.
  Soluble nutrients are found in the liquid, which
  should be eaten with the fruit.
• Boiling inactivates the enzymes in the fruit,
  preventing it from turning brown.

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8. Summary

• By the end of this lesson, you should be able
  to
• Understand the features of different types of
  foods
• List the nutritive composition of the various
  foods cereals, meat, fish, eggs, dairy products,
  pulses, legumes, vegetables and fruit.
• Choose food commodities wisely.
• Explain how food are used in cooking and their
  chemical changes.