What is the Chemistry of Food

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What is the Chemistry of Food?

• Chapter 11
• Basic Chemistry
• WZPP

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What is the Chemistry of Food? bc 11-Introduction

• Our human bodys need for energy and growth comes
  from the food we eat
• Many people in the world today die from
  starvation
• In the wealthy countries, there is an
  overabundance of food
• But many people do not know how to eat properly

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Where Does Food Come From?bc 11-1

• Every food is traced back to a green plant
• nCO2 nH2O Sunlight? Cn(H2O)n O2
• Carbon dioxide water ?with sunlight?
  glucose oxygen

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Where Does Food Come From?bc 11-1

• Chemicals needed to make up food
• Comes from the Earth itself
• Carbon is found in all living things
• Carbon must be consumed in the food that we eat
• Carbon is not an abundant element
• It must be recycled from past living things

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What Do We Need from Food?bc 11-2a

• We need 6 major components from food to sustain
  life
• These are called nutrients
• Carbohydrates
• Proteins
• Fats
• Minerals
• Water
• Vitamins

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How are Carbohydrates Essential for Life?bc 11-2b

• Carbohydrates is a compound with Carbon, Hydrogen
  and Oxygen
• General formula
• Cn(H2O)n
• Is in different forms
• Wood (cellulose), sugar, starch

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How are Carbohydrates Essential for Life?bc 11-2b

• In digestion, all carbohydrates are reduced to
  glucose
• Glucose is burned in our cells to release energy
• C6H12O6

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How are Carbohydrates Essential for Life?bc
11-2b drawings
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How are Carbohydrates Essential for Life?bc 11-2b

• Starch and sugar are essential in human nutrition
• Is the source of about 80 of our bodys energy
• Our bodys cells burn carbohydrates (glucose)
  very efficiently
• But fats burn very slowly

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How are Carbohydrates Essential for Life?bc 11-2b

• Refined sugars like Sucrose (cane sugar) are poor
  sources of nutrition
• Causes the release of cholesterol in the blood
• Cholesterol is a major contributor to heart
  disease

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How are Carbohydrates Essential for Life?bc 11-2b

• Complex carbohydrates
• Like potatoes, pasta, rice, whole-grain cereals
• Are essential part of human nutrition

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How are Carbohydrates Essential for Life?bc 11-2b

• When food is digested its nutrients are reacted
  with water
• nH2O (C6H10O5)n ?DIGESTION? nC6H12O6

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How are Carbohydrates Essential for Life?bc 11-2b

• Glucose fuels our cells
• nC6H12O6 6 O2 ????? 6 H2O 6 CO2 energy

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How are Proteins Essential for Life?bc 11-2c

• All living things are made of proteins
• Proteins in your body are made of amino acids
• Proteins are needed to replace lost tissue
• Nonessential amino acids
• Are made by our own cells
• Essential amino acids
• Are amino acids that are not made by our cells

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How are Proteins Essential for Life?bc 11-2c

• Animal proteins
• Is from fish, fowl, meat, eggs and milk products
• Is complete protein
• Has all the essential amino acids

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How are Proteins Essential for Life?bc 11-2c

• Vegetable (plant) protein
• Are incomplete
• Dont have all the essential amino acids
• Add beans rice will give you all the essential
  amino acids

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How are Fats Essential for Life?bc 11-2d

• Made of long chains of carbon and hydrogen
• Saturated fats
• Have only single bonds between the carbon atoms
• May interfere with the bodys ability to cope
  with cholesterol
• examples of saturated oils
• Coconut, Palm, hydrogenated vegetable oil

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How are Fats Essential for Life?bc 11-2d

• Polyunsaturated Fats
• Have many double bonds between carbon atoms
• Able to reduce the cholesterol in the blood
• Polyunsaturated oils (corn oil, safflower oil)
• Are vulnerable to oxidation near the double bond
• Oil will turn rancid, food will taste spoiled

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How are Fats Essential for Life?bc 11-2d

• Fats are burned for energy in your body
• Fats help to insulate and protect our bodies
  tissues
• Many food components (vitamins A, D, K E) are
  soluble in fats
• Fats are digested to fatty acids and glycerol

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How are Fats Essential for Life?bc 11-2d
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How are Minerals Water Essential for Life?bc
11-2e

• Calcium
• Needed for bones teeth, blood clotting
• Sources
• Milk
• Milk products
• cheese

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How are Minerals Water Essential for Life?bc
11-2e

• Phosphorus
• Needed for strong bones teeth
• Is in the formation of ATP
• Which plays part in nearly every chemical
  reaction of the body
• Sources
• Cheese
• Milk
• Meats
• Poultry
• Fish

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How are Minerals Water Essential for Life?bc
11-2e

• Iron
• Needed for red blood cells to carry oxygen
• Sources
• Liver
• Yeast
• Lean meats
• beans

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How are Minerals Water Essential for Life?bc
11-2e

• Water
• Cant live without water for more than a few days
• Dissolves transports other nutrients
  throughout the body
• Aids in digestion, absorption, circulation
  excretion
• Helps to regulate body temperature
• Source
• Water

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How are Minerals Water Essential for Life?bc
11-2e

• The average adults body contains about 40 quarts
  of water
• A mans body is 60 to 65 percent water
• A womans body is 50 to 60 percent water

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How were Vitamins discovered?bc 11-2f

• People have know for many years that disease can
  result from food deficiency
• Sailors prevented scurvy by eating fresh fruits
  and vegetables
• An experiment with the diet of rats proved the
  existence of vitamins when the rats became ill

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How is Vitamin A Essential for Life?bc 11-2g

• Is the first fat-soluble food factor identified
• Lack
• Loss of weight
• Increased chance of infection
• Prevents
• The eye disease that the eye tissues dry up
• Prevents night blindness
• Promotes good eye sight and skin

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Rat A, B1bc 11-2g
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How is Vitamin A Essential for Life?bc 11-2g

• Is stored in the liver
• Too much can be poisonous
• (like 10,000 x the normal amounts)
• Sources
• Liver
• Fortified milk
• Carrots
• Broccoli

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How are B-Complex Vitamins Essential for Life?bc
11-2h

• Vitamin B-1 or thiamine
• Is needed for carbohydrate metabolism
• Prevents beriberi
• Which causes paralysis, anemia and weakness
• Is sensitive to heat
• 20 to 50 of the vitamin is lost in cooking
• Is neutralized by some vegetables
• Like soybeans, red cabbage, beets, Brussels
  sprouts

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How are B-Complex Vitamins Essential for Life?bc
11-2h

• B-complex vitamins
• All are water soluble
• Sources include
• Brewers yeast, wheatgerm, milk, whole grain
  cereals, and brown rice

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How is Vitamin C Essential for Life?bc 11-2i

• Is contained in all citrus fruit
• Cannot be stored in the body
• Must be consumed each day
• Lack of vitamin C makes you more vulnerable to
  infection and having cavities
• Can be destroyed by heat and exposure to air
• Helps with tissue repair and to heal wounds

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How is Vitamin D Essential for Life?bc 11-2j

• Called the sunshine vitamin
• Is fat soluble
• Is important for strong bones (bone development)
  and teeth
• Prevents the disease called rickets
• Can be poisonous if taken in large doses
• Other sources include
• Fortified milk, fish oils

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How is Vitamin E Essential for Life?bc 11-2k

• Needed for growth and development
• Needed for normal blood formation
• 
  not found in text
• Is found in
• Green lettuce leaves, whole grain cereals, beef
  liver, egg yolk and wheatgerm oil

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How is Vitamin K Essential for Life?bc 11-2l

• Is involved in the clotting of blood
• Is found in
• Green leafy vegetables

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How Does Cooking Change Our Food?bc 11-3a

• There are several ways to prepare food
• Fry
• Broil
• Bake
• Roast
• Boil

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How Does Cooking Change Our Food?bc 11-3a

• Cooking changes
• The appearance
• The flavor of foods
• The nutritional values of food

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What Happens to Food When We Fry It?bc 11-3b

• Food that is fried absorbs fats oils
• Proteins begin to be digested in the stomach and
  finish in the small intestine
• Fats begin to be digested in the small intestine
• The fats absorbed by the foods inhibit the start
  of protein digestion

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What Happens to Food When We Fry It?bc 11-3b

• Many vitamins (like B-complex C) are destroyed
  by the heating of frying

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What Happens to Food in Baking?bc 11-3c

• Baking food is inefficient
• Air is so thin at high temperatures that few
  molecules come in contact with the food

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What Happens to Food in Baking?bc 11-3c

• Bread is made leaven by adding yeast or baking
  power
• Each method produces carbon dioxide gas
• Causes bread to rise
• Makes bread easier to chew and digest

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How does Boiling Change Food?bc 11-3d

• Vegetables are composed of cells surrounded by
  wood, or cellulose cells
• By boiling, plants lose its rigid structure
• Pectin dissolves between cell walls

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How do Microwave Ovens Cook Our Food?bc 11-3e

• Is a form of radiant energy
• Microwave energy is useful in cooking because
  the energy is absorbed by water and converted
  into heat inside if the food
• The water boils off as steam
• Food is quickly cooked internally as if it were
  steamed

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How do Microwave Ovens Cook Our Food?bc 11-3e

• Since the air inside of the oven remains cool,
  the food is not baked

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How do Microwave Ovens Cook Our Food?bc 11-3e

• Microwave ovens are generally safe
• There is a danger of microwave leakage
• The microwaves could be absorbed by people who
  are exposed to the waves
• The power is too low to cause immediate injury
• People with pacemakers need to be very cautious
  near microwave ovens

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How can Food be Preserved?bc 11-4

• Meats and vegetables will rot or decay due to
  action of microorganisms
• Preserving food slows down this action

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How can Food be Preserved?bc 11-4

• Drying (adding salt)
• Draws moisture from the meat
• Microorganisms must have water to survive

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How can Food be Preserved?bc 11-4

• Cooking
• Heating destroys microorganisms

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How can Food be Preserved?bc 11-4

• Refrigeration
• Slows down microorganism activity

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How can Food be Preserved?bc 11-4

• Canning
• Cooked food is sealed in a can
• Swollen cans may indicate microorganism are
  growing in the can
• Botulism is caused by consumption of spoiled food
• 
  
  End notes bc 11