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PringlesCalories Fat Satur-
ated FatCost
Regular Pringles
150 9 2.5 $1.00
Light Pringles
70 0 0 $2.58
Lipids, like carbohydrates, contain carbon, hydrogen, and oxygen.
But lipids do not provide structure to food products and they cannot dissolve in water.
Most lipid molecules found in foods and the body have two basic parts.
The base or core is a glycerol molecule called glycerides.
The second part of most molecules is called a fatty acid.
Glycerides – 1st type of lipid
Monoglycerides – is a glycerol with one fatty acid attached at the site of a hydroxyl group.
Diglycerides – is a glycerol with two fatty acids attached.
Triglycerides – have a fatty acid joined at each of the three hydroxyl sites.
Phospholipids- 2nd type of lipid
A second basic type of lipid that has a glycerol base with two fatty acids AND a phosphorus-containing acid attached.
The fatty acids are soluble in water.
This allows phospholipids to mix with both water-based and fat-based substances.
Phospholipids- 2nd type of lipid
Phospholipids help carry fats back and forth across cell membranes into the water-based fluids.
In food products, phospholipids keep foods like mayonnaise from separating.
Sterol – 3rd type of lipid
Complicated molecules derived or made from lipids.
Examples: cholesterol, vitamin D, steroid hormones.
Cholesterol is a part of every cell in the human body.
To understand the effects of
lipids in food mixtures,
you need to understand
the ways lipids are categorized.
Lipids are grouped according to:
molecular structure
physical state at room temperature
dietary sources
Molecular Structure (category)
One way to categorize lipids is by how
saturated their carbon chains are
with hydrogen atoms.
Molecular Structure (category) Each carbon atom is capable of
forming 4 bonds. A carbon atom can bond twice to
another carbon atom. This is called a double bond.
Fatty acids will have 0, 1, or multiple double bonds.
Molecular Structure (category)
When fatty acids have the maximum number of hydrogen atoms, they are saturated.
Examples: butter, shortening, coconut oil
Molecular Structure (category)
Fatty acids that have one double bond in the carbon chain are called monounsaturated.
Examples: olive oil, almonds, walnuts, canola oil
Molecular Structure (category) Polyunsaturated fatty acids have
two or more double bonds in the carbon chain. Each double bond bends the fatty acid chain. Bends make it difficult for the molecules to pack together tightly.
Examples: safflower, sunflower, and
corn oil
Physical State (category)
Lipids that are solid at room temperature are called fats.
Lipids that are liquid at room temperature are called oils.
Physical State (category)
Hydrogenation – adding hydrogen atoms to an unsaturated fat to increase its saturation level.
Physical State (category)
Advantages of hydrogenated vegetable oil: Longer shelf life than oil Greater stability than lard Costs less than lard Faster dissolving and setting properties in
chocolate
Food Source (category)
Milk fats come from the milk of cows or goats.
Lauric acids come from palms of coconut.
Vegetable butters come from seeds of tropical plants.
Oleic-linoleic acids come from corn, peanuts, sunflowers, or olives
Food Source (category)
Linolenic acid comes from soybeans and wheat germ.
Animal fats are found in meat and poultry.
Marine oils come from fish.
Functions of Lipids in Food Preparation
Transfer heat
Tenderize
Aerate (add air to a batter)
Enhance flavor
Lubricates
Liquids in emulsions
Functions of Lipids in Food Preparation
Transfer heat – lipids will continue to increase as heat is added; every lipid has a smoke point and a flash point.Smoke point – temperature at which the
fatty acids begin to break apart and produce smoke.
Flash point – temperature at which lipids flame.
Functions of Lipids in Food Preparation
Tenderize – fats tend to shorten the
long protein strands of flour of most
baked goods, thereby, tenderizing the
baked good.
Functions of Lipids in Food Preparation
Aerate (add air to a batter) –
saturated fat has the ability to allow
tiny air pockets to form when batters
are beaten sufficiently. If over-beaten,
fat could melt and then air pockets
are lost.
Functions of Lipids in Food Preparation
Enhance flavor – fats add flavor,
helps transfer and intensify flavor.
Examples: Butter adds flavor to
bread; onions and garlic cooked in fat
will be stronger than if cooked in a
broth base.
Functions of Lipids in Food Preparation
Lubricates – makes food seem
moister and easier to chew.
Examples: Marbling in meat;
mayonnaise spread on sandwiches
Functions of Lipids in Food Preparation
Liquids in emulsions – usually one
of two liquids in an emulsion – a
mixture that contains a lipid and a
water-based liquid.
Examples: mayonnaise; bottle salad
dressings
Lipids in Your Diet - Functions
Concentrated source of energy – 9
calories / gram
Cell production – cell walls made of
lipids and proteins
Lipids in Your Diet - Functions
Temperature regulation – fatty tissue
insulates and holds body warmth
Helps transport vitamins – some
vitamins needs fat to be transported
Essential Fatty Acids
Fatty acids that the body cannot produce:Linoleic acidLinolenic acid
Both of these are polyunsaturated Both are found in most plants and fish oils Essential for growth and development
Role of Cholesterol
Used to build cell membranes – it is a rigid molecule that helps solidify cell walls; adds stability to cell’s structure
Body makes cholesterol from lipids
Atherosclerosis
Results when there is too much cholesterol in the blood
Too much blood cholesterol causes deposits called plaque.
The rigidity of the cholesterol plaque deposits on the walls of arteries hardens the arteries. This hardening is called atherosclerosis.
Lipoproteins These are clusters of lipid and protein
molecules. Transports cholesterol throughout the body LDL (Low-density lipoproteins) carry
cholesterol from the liver HDL (High-density lipoproteins) find
unneeded cholesterol and return it to the liver. LDL and HDL work together to keep
cholesterol in balance.