Download Testing for Carbohydrates Fats Proteins

Unit
Food Science
Problem Area
Handling and Storing Plant
Products
Lesson
Testing for Carbohydrates,
Fats, and Proteins
Student Learning Objectives
 1. Explain why proper nutrition is important for all
organisms.
 2. List the six essential nutrients needed by organisms
and explain their overall importance.
 3. Explain the importance of water in the body.
 4. Explain how minerals are important to organisms.
 5. Explain the importance of vitamins to organisms.
 6. Explain the importance of protein for organisms.
 7. Explain why carbohydrates are essential to the
survival of organisms.
 8. Explain the importance of lipids.
Terms
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Adhesion
Amino acids
Capillarity
Carbohydrates
Catalyst
Cohesion
Disaccharides
DNA
Enzymes
Fat soluble vitamins
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Inorganic compounds
Lipids
Macrominerals
Minerals
Monosaccharides
Nucleic acids
Nutrients
Nutrition
Organic compounds
Polar compound
Terms cont.
 Polysaccharides
 Polyunsaturated fatty
acid
 Proteins
 RNA
 Saturated fatty acid
 Steroids
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Trace elements
Triglycerides
Vitamins
Water
Water soluble vitamins
Wax
Why is proper nutrition important for all organisms?
 A. Three Needs of Humans/Organisms
1. Food—Food provides energy.
2. Water—Water is necessary for a variety of
chemical reactions to occur and is the primary
solvent in our bodies.
3. Shelter—Our homes and clothing protect
from the extremes of the environment.
 B. Nutrition is the process by which animals eat
food and use it to live, grow and reproduce.
Proper nutrition allows us and all other
organisms to function at optimal levels.
Nutritional stress inhibits our ability to function.
Early sailors learned to take limes with them to
prevent scurvy due to a deficiency of Vitamin C
even though we really have only known about
Vitamin C for a few short decades.
 C. Proper Nutrition for animals and plants
causes:
1. Increased feed efficiency for livestock as well
as domesticated and wild animals.
2. Increased rate of gain provides bigger
financial yields for farmers.
3. Decreased days to market weight enables
farmers to increase their overall production and
profit.
4. Increased plant performance and efficiency
again increases profit.
5. Improved nutritional value of foodstuffs.
 D. Poor nutrition results in lower production and
returns because of:
1. Slow plant and animal growth
2. Poor reproduction
3. Lowered production levels
4. Poor health
5. Increased death loss
What are the nutrients that organisms need and how do they
help organisms function?
 Nutrients are substances that are necessary for the
functioning of an organism.
 A. Six Essential Nutrients
 1. Water is the primary component of all organisms. It is the
primary solvent in the body which contains all of the dissolved
and suspended solutes providing the transportation system for
the body.
 2. Minerals are an important component of the skeleton, soft
tissues, and fluids.
 3. Vitamins act as a catalyst in body processes; vitamins help
chemical reactions to occur in the body.
 4. Proteins are used to build and repair cells.
 5. Carbohydrates provide energy.
 6. Lipids provide and store energy.
 B. These six essential nutrients are all equally
important to the peak performance of all
organisms including humans.
 C. Water, minerals, and vitamins are all
inorganic compounds and protein,
carbohydrates, and lipids are all organic
compounds. Organic compounds contain
carbon, hydrogen, and oxygen and come from
living things. Inorganic compounds can contain
carbon, hydrogen, and oxygen, but they come
from the earth rather than from organisms.
Why is water important to the body?
 Water is the most important inorganic compound
in living things.
 A. Water is an excellent solvent and has a high
heat capacity.
 B. Water makes up about 70–80 percent of
plants and about 75 percent or more of muscles
and internal organs in animals.
 C. Water serves many different purposes.
1. Our body is made up a variety of solutions. A solution
consists of solutes and solvents. A solute is the
substance that is dissolved in the solution. The solvent
is the substance that dissolves the solute. Using a glass
of sweet ice tea as an example—the solutes are the tea
and the sugar and water is the solvent. Water is the
solvent in which all nutrients (solutes) are dissolved and
suspended.
2. Water reacts with many chemical compounds to
break down food.
3. Water provides rigidity for plants.
4. Water regulates body temperature.
 D. Chemical properties of water are unique and aid to its universal
importance.
 1. Cohesion is the bonding of water molecules to each other.
This can be evidenced in a puddle of water on a table. Water is a
polar compound. Water has a net charge of zero (one
hydrogen and two oxygen atoms bond resulting no charge).
However, because of the molecular structure (how the atoms
bond together), a water molecule has an imbalance in its charge
resulting in a slightly negative pole and a slightly positive pole.
Because of this, water molecules bond to other water molecules
very easily.
 Water’s high heat capacity is due to its polarity; it takes a great
deal of heat or energy to break the bonds between water
molecules. This is why it takes a pot of water a seemingly long
time to boil; the heat must work to break the bonds before the
water will boil. This characteristic is good for organisms because
we would die if a small amount of heat were needed such as
from the sun to cause us to “boil.”
 2. Adhesion is the bonding of water molecules to other
substances. Again water bonds to other substances easily
because of polarity, especially other polar compounds. A
small drop of water will adhere to the side of your car or to
the wall.
 3. Capillarity is the ability of a liquid to move upward
against the force of gravity by molecular attraction to a
surrounding surface. Water is able to move from the roots
of a plant to the leaves because of cohesion and adhesion.
Looking at a clear graduated cylinder will help to visualize
how capillarity works in plants. The water bonds to the
inside of the graduated cylinder due to adhesion. Water
molecules bond to themselves due to cohesion. As the
water moves up the sides of the cylinder due to adhesion,
cohesion pulls more water molecules upward. The
narrower the tube, the faster the liquid will move upward
against the force of gravity.
Why are minerals important to organisms?
 Minerals are found in rocks, soil, and water and are
essential to the body for optimal performance.
 A. The primary purpose of minerals is that they become
part of the body making up bones, fluids, and tissues.
 B. Macrominerals are needed in large quantities.
Macrominerals include sodium, calcium phosphorus,
potassium, and magnesium.
 C. Trace elements are needed in smaller quantities, but
are just as important to your health. Copper, tin, iodine,
and iron are examples of trace elements.
 D. Many ailments can be attributed to a low mineral
intake. Thus, many doctors recommend that humans
take vitamin and mineral supplements.
1. Anemia or a feeling of tiredness can be attributed to
low iron levels.
2. Fatigue, rapid pulse, and increased appetite can
result form low levels of iodine.
3. Muscle tremors or shaking can result from insufficient
levels of magnesium.
4. Low calcium levels can result in poorly formed teeth
and bones resulting in Osteoporosis or brittle bone
disease. Calcium is needed for a variety of chemical
reactions and muscle contractions to occur.
Osteoporosis can result from the body’s compensation
of a lack of calcium by removing it from the bones.
Why are vitamins important to organisms?
 Vitamins serve as a catalyst in the body meaning that
they cause chemical reactions to occur. They do not
provide energy or build the body.
 A. Vitamins serve many purposes including:
1. clotting of blood
2. formation of bones
3. aiding reproduction at both the cellular and
multicellular levels
4. keeping membranes healthy
5. producing milk
6. prevention of certain nervous system disorders
 B. Vitamins can be classified as either fat
soluble or water soluble.
1. Water soluble vitamins include vitamins C
and B. This means that the vitamins must be
consumed every day because your body uses
C and B vitamins as they are needed. Excess
amounts of these are excreted from the body.
2. Fat soluble vitamins include vitamins A, D,
E, and K. These vitamins are stored in the body
and used as needed.
 C. Vitamins are essential to the proper
functioning of the body, but they are needed in
very small amounts. The recommended daily
allowance of Vitamin C is only 60 mg, but one
ounce of Vitamin C contains 28,000 mg. Large
doses of vitamins can have negative effects on
the body as well.
 D. Animals receive most of the vitamins that they
need through their feed, but supplements can be
purchased to add to their ration.
 E. Vitamins are usually made up of carbon,
hydrogen, oxygen, and nitrogen.
Why do organisms need protein?
 Living things are made up of many different chemical
molecules. After carbohydrates, protein is the second
most abundant nutrient found in plants. Proteins make
up the bulk of all solid material within your body and the
bodies of other animals. Your muscle, skin, hair, and
inside organs are largely protein. Proteins are essential
for body growth and repair.
 They also make up some hormones which function in
chemical control in the body and are found in enzymes
and antibodies. There are many kinds of proteins found
in plants and they are classified by their origin. Protein
deposited in seeds is the major source for human
consumption. Protein is essential for many of life’s
biological processes.
 A. The main purpose of protein is to build and
repair cells. Three to five percent of the body’s
cells are rebuilt every day. Protein is also the
major component of the body’s genetic code.
Proteins are an organic compound that is
composed of one or more chains of
polypeptides. Polypeptides are in turn made
from amino acids.
 B. Amino acids are monomers (single chemical
units) that form proteins.
 1. Each amino acid contains a central carbon
atom and four other atoms or groups that bond
covalently to the carbon atom. Different amino
acids have different “R groups.”
2. There are only 20 known amino acids, but there are
thousands of different proteins. The human body can
manufacture only 11 of the 20 amino acids. The other nine
are called essential amino acids and must be consumed
through the food that is eaten.
 C. A dipeptide is two amino acids bonded together. A
polypeptide is a long chain of amino acids. Proteins are
composed of 2 or more polypeptides.
 D. Enzymes are proteins that act as catalysts in
intermediary metabolism which is a series of chemical
reactions in which energy is released in slow controlled
amounts so that cells will not be damaged. Enzymes lower
the activation energy that is needed thus decreasing the
amount of activation energy that is needed for a chemical
reaction to occur.
 E. Nucleic Acids are complex organic molecules that
store important hereditary information in the cell’s
nucleus.
 1. DNA or deoxyribonucleic acid is hereditary information in the
form of a large molecule. DNA stores all of the essential
information that is needed for directing all of the cell’s activities.
 2. RNA or ribonucleic acid stores and transfers information that
is essential for the manufacturing of proteins. RNA is found in
the nucleus and in the cytoplasm of the cell.
 F. Foods high in protein include beans, meat, nuts,
cheese, and eggs. Feedstuffs high in protein include
soybeans, peanuts, cottonseed, linseed, and urea
(nonprotein nitrogen). Protein from animal sources is
usually of a higher quality than plant protein. Nutritionists
recommend that about 15 % of the human diet should be
made up of protein.
Why are carbohydrates important for organisms?
 Carbohydrates are organic compounds that are
the main source of energy for organisms. If low
levels are carbohydrates are consumed, the
body will use fat and protein for energy. This can
result in insufficient levels of fat and protein to
perform other vital functions.
 A. Carbohydrates are composed of carbon,
hydrogen and oxygen. The number of carbon
atoms will vary, but the hydrogen and oxygen
atoms will be found in a ratio of 2:1. Water is
also found to have a 2:1 ratio.
 B. There are three types of carbohydrates.
1. Monosaccharides are simple sugars or single
molecule sugars. They contain 1 carbon: 2 hydrogen: 1
oxygen. The most common monosaccharides are
glucose, fructose, and galactose; all have a chemical
formula of C6 H12 O6 . Molecules that have the same
molecular composition, but have different structures are
called isomers.
a. Glucose is the main source of energy for plants
and animals is created during photosynthesis (H2
O+CO2 + light à O2 +C6 H12 O6 ).
b. Fructose is found in fruits and is the sweetest of all
the monosaccharides.
c. Galactose is found in milk.
 2. Disaccharides are double sugars.
a. Lactose is found in milk and is formed from
glucose and galactose.
b. Sucrose is created from fructose and glucose and
is found in sugar cane and sugar beets.
c. Maltose is formed from two glucose molecules.
3. Polysaccharides are complex molecules containing
three or more monosaccharides.
a. Glycogen is how animals store glucose.
b. Starch is how plants store glucose. Starch is found
in potatoes, bread, vegetables, and rice. Plants are
the primary producers of carbohydrates.
c. Cellulose is found in plants and is indigestible by
humans. Ruminants are able to digest cellulose
because of the presence of microorganisms in their
stomach.
 C. Nutritionists recommend that about 55% of the human diet
be composed of carbohydrates. Humans should consume
plenty of fruits, vegetables, and whole grain breads.
 D. Unused carbohydrates are converted to fat and are stored
in the body for future use.
 E. The storage form of carbohydrates found in tuber, bulbs
and roots is starch. Two forms of starch are known: amylose
and amylopectin. Carbohydrates in the form of starch are not
used by the plant because starch is insoluble in water.
However, plants manufacture the enzyme amylase which
breaks starch down into soluble sugars for use by the plant.
Amylase is an enzyme important in germination because it
breaks down the starch present in seed to provide energy for
the growing seedling. Starch is easily digested by animals and
an important source of energy.
Why do organisms need lipids to survive?
 Lipids are important chemical molecules that are present
in living organisms. Lipids are a fatty compound made up
of carbon, hydrogen, and oxygen. They do not dissolve
in water and thus are referred to as hydrophobic.
 A. Lipids are used for storage of energy, to add flavor to
food, for a healthy skin and hair, for the nervous system,
and for a variety of chemical processes. Lipids can be
added to animal feeds helping to improve flavor,
palatability, texture, and energy levels. Lipids are also
needed to carry and store fat soluble vitamins. Fat
soluble vitamins include vitamins A, D, E, and K.
 B. The three primary types of lipids include triglyceride,
wax, and steroid.
1. Triglyercides are made up of three fatty acid
molecules and one glycerol molecule. Examples of
triglycerides include oils and fats.
a. Oils are triglycerides that are liquid at room
temperature and are typically found in the seeds of
plants.
b. Fats are solid at room temperature and are found in
animals.
2. Wax is a lipid consisting of a long fatty acid joined to
a long alcohol chain. Because waxes are highly
waterproof, they are found in the waxy coating of leaves
and in ears.
3. Steroids include cholesterol and cortisone and are
found in hormones, nerve tissue, and plant poisons.
 C. Lipids are created when a molecule of glycerol is joined to any
number of fatty acids. Examples of fatty acids include lauric acid,
butyric acid, and caproic acid.
 1. Some fatty acids are made by the body. Essential fatty acids
are not made in the body and must be consumed. Therefore, a
no fat diet is not acceptable.
 2. Depending upon how much hydrogen is found in a fatty acid
determines whether it is saturated or polyunsaturated. When the
molecule is completely full of hydrogen, it is called a saturated
fatty acid. Saturated fats are solid at room temperature and are
primarily found in meat and coconut.
 3. Fats that are liquid at room temperature are called
polyunsaturated fatty acids. They are found in fish and in
plants.
 4. Hydrogenation is a process where polyunsaturated fats can be
made solid at room temperature. Whipped topping and
margarine are examples of foods created through this process.
 D. Most fats found in plants are deposited in the seed.
For example, coconut contains 65% crude fat, soybeans
15–20% crude fat and corn contains approximately 59%
crude fat. Fats are the most concentrated food energy
source.
 E. In the United States, fat contributes nearly 50% of the
calories in the average diet. Recent studies linking high
fat diets with cardiovascular disease and elevated
cholesterol levels in the blood have caused people to cut
back on their daily consumption of fat. Usually this has
meant that persons eat less red meat and eggs, but it is
also necessary to monitor intake of saturated fats from
plant products as well.
 F. Most doctors agree that an average person
should consume about 30% of their daily caloric
intake as fat and should have their body fat
percentage be around 20% depending on
various factors. Fats are an important part of the
diet.
 G. Foods containing lipids include margarine,
butter, chips, plant oils, nuts, meat, eggs,
cheese, milk, and ice cream.
Review/Summary
 Why is proper nutrition important for all
organisms?
 What are the nutrients that organisms need and
how do they help organisms function?
 Why is water important to the body?
 Why are minerals important to organisms?
 Why are vitamins important to organisms?
 Why do organisms need protein?
 Why are carbohydrates important for
organisms?
 Why do organisms need lipids to survive?