There are two types of fatty acids, saturated and unsaturated.
There are a variety of organic compounds.
The compounds are insoluble in water.
Hydrogens only to carbon have no tendency to form hydrogen bonds with water.
The majority of fat is found beneath the skin of most animals, where it helps retain body heat.
We know how to cook with fats and oils because we consume them as food.
They are also being used as an alternative fuel source for industrialized societies.
The important lipids found in living organisms include the triglycerides, steroids, and waxes.
The structure and function of these classes of lipids will be explored in the next sections.
Triglycerides are composed of fat and cholesterol.
The chain has an even number of carbons and acarboxylates at one end.
The cells contain 16 or 18 carbon atoms per molecule of the fatty acids.
The fatty acid chains are either saturated or unsaturated.
Double bonds in the carbon chain reduce the number of hydrogen atoms.
A trans fat has at least one bond in a trans configuration.
The cis or trans configuration of an oil affects its activity.
Saturated and unsaturated fat acids.
A long hydrocarbon chain has a carboxyl group attached to it.
There are no double bonds between the carbons in the chain.
If there are double bonds between some of the carbons, there is a problem with the chain.
Glycerol is a compound with three groups.
soluble glycerol is made in water by the --OH groups.
When a fat or an oil forms, the --COOH functional groups of three fatty acids react with the -- OH groups of glycerol during a dehydration reaction, resulting in a fat molecule and three molecule of water.
Fats and oils are degraded.
triglycerides don't mix with water because they have many nonpolar C--H bonds.
Even though cooking oils and water are both liquid, they don't mix because they are incompatible.
As fat forms and water is given off, glycerol is bonding to three fatty acid molecules.
The bonds are broken due to the addition of water.
The temperature at which the Triglycerides melt is lower than the temperature at which the saturated Triglycerides melt.
The reason is that a double bond creates a kink in the chain that prevents close packing.
Butter is a fat that is solid at room temperature and is composed of saturated fatty acids, whereas corn oil is a liquid even when placed in the refrigerator.
This difference is useful to living organisms.
The feet of reindeer and penguins have a substance in them that helps protect them from freezing.
Fats from animals are solid at room temperature, whereas oils from plants are liquid at room temperature.
Diets high in animal fat are associated with circulatory disorders because saturated fats can accumulate inside the lining of blood vessels and block blood flow.
Replacing fat with oils such as olive oil and canola oil is recommended by health organizations.
Fat is used for long-term energy storage.
The C--H bonds of fatty acids make them a richer source of chemical energy than glycogen because they have more bonds with stored energy.
Fat droplets do not have water in them.
Small birds, such as the broad-tailed hummingbird, store a lot of fat before they start their long migratory flights.
Each day, 0.15 g of fat is accumulated.
A bird would not be able to fly if it had the same amount of energy as glycogen.
Saturated fats and trans fats should be limited in your diet.
Saturated fats, which come from animals and are solid at room temperature, have effects in the body that are different from those of unsaturated fats, which come from plants and are liquid at room temperature.
Too much saturated fat has been shown to contribute to the formation of arteries and cardiovascular disease.
Unsaturated fats don't stick together in the blood and therefore don't cause arteriosclerosis.
Plant oils can easily go rancid and aren't solid at room temperature, which makes them more difficult to cook with and to use in solid food products.
The treatment made the plant oils semisolid at room temperature and gave the partially hydrogenated oils better shelf life.
Many commercially packaged foods contain trans fats, which have been shown to increase bad cholesterol and lower good cholesterol levels in the blood.
Trans fat consumption increases the risk of cardiovascular disease.