What are the differences between saturated and unsaturated fatty acids?

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Accepted Answer

Saturated fatty acids are the simplest form of fats. The term saturated indicates that each carbon atom in a fat molecule is bonded with the maximum number of hydrogen atoms. Unsaturated fatty acids are more complex. The term unsaturated indicates that the carbon atoms do not have the maximum number of hydrogen bound to them. Here’s a more detailed look at the differences between saturated fatty acids and unsaturated fatty acids.

Basis of differentiation
Saturated fatty acids
Unsaturated fatty acids

Definition
Are the simplest form of fats - are unbranched linear chains of CH2 with only single bonds between carbon atoms and no unsaturated linkages indicating an inability to absorb any more hydrogen atoms
Are more complex fatty acids in which the bent hydrocarbon chains are linked together by one or more carbon-carbon double bonds indicating the potential to absorb additional hydrogen atoms

Characteristic of bonds
Have only a single bond, lack carbon-carbon double bonds
May have one or more carbon-carbon double bonds

Configuration
Trans and cis configuration are not possible
May exist in cis or trans configuration

Hydrogen atoms
Carbon atoms have the maximum possible hydrogen atoms bound to them
Do not have maximum possible hydrogen atoms bound to the carbon atoms

Characteristic of hydrocarbon chain
Hydrocarbon chains are linear and unbranched
Hydrocarbon chains are bent and branched

Potential for hydrogenation
Hydrogenation is not possible as the maximum number of hydrogen atoms are bound to the carbon molecule and no more hydrogen atoms can be added to the hydrocarbon chain
Hydrogenation is possible because the carbons atoms do not have the maximum possible hydrogen atoms bound to them – hydrogenation converts unsaturated fatty acids to saturated fatty acids

Composition
Make up the fat part of lipids
Make up the oil part of lipids

Sources
Typically found in animal fats such as whole milk, butter, and meat
Typically found in plant sources such as olive oil, sunflower oil, avocado oil, and mustard oil

Storage
Stored under the skin and in the liver in mammals
Stored in the form of fat granules in the seeds and fruits of plants

State at room temperature
Exist in the solid state at room temperature 
Exist in the liquid state at room temperature

Melting point
Higher melting point
Lower melting point

Shelf life
Longer shelf life – can be stored for longer periods of time without getting rancid or spoiling
Shorter shelf life – will get rancid and spoil when stored for long periods

Solubility in vitamins
Soluble in vitamins
Insoluble in vitamins

Common Examples
Palmitic acid, stearic acid, lauric acid, arachidic acid, and myristic acid
Oleic acid, linoleic acid, linolenic acid, palmitoleic acid, and arachidonic acid

Basis of differentiation	Saturated fatty acids	Unsaturated fatty acids
Definition	Are the simplest form of fats - are unbranched linear chains of CH2 with only single bonds between carbon atoms and no unsaturated linkages indicating an inability to absorb any more hydrogen atoms	Are more complex fatty acids in which the bent hydrocarbon chains are linked together by one or more carbon-carbon double bonds indicating the potential to absorb additional hydrogen atoms
Characteristic of bonds	Have only a single bond, lack carbon-carbon double bonds	May have one or more carbon-carbon double bonds
Configuration	Trans and cis configuration are not possible	May exist in cis or trans configuration
Hydrogen atoms	Carbon atoms have the maximum possible hydrogen atoms bound to them	Do not have maximum possible hydrogen atoms bound to the carbon atoms
Characteristic of hydrocarbon chain	Hydrocarbon chains are linear and unbranched	Hydrocarbon chains are bent and branched
Potential for hydrogenation	Hydrogenation is not possible as the maximum number of hydrogen atoms are bound to the carbon molecule and no more hydrogen atoms can be added to the hydrocarbon chain	Hydrogenation is possible because the carbons atoms do not have the maximum possible hydrogen atoms bound to them – hydrogenation converts unsaturated fatty acids to saturated fatty acids
Composition	Make up the fat part of lipids	Make up the oil part of lipids
Sources	Typically found in animal fats such as whole milk, butter, and meat	Typically found in plant sources such as olive oil, sunflower oil, avocado oil, and mustard oil
Storage	Stored under the skin and in the liver in mammals	Stored in the form of fat granules in the seeds and fruits of plants
State at room temperature	Exist in the solid state at room temperature	Exist in the liquid state at room temperature
Melting point	Higher melting point	Lower melting point
Shelf life	Longer shelf life – can be stored for longer periods of time without getting rancid or spoiling	Shorter shelf life – will get rancid and spoil when stored for long periods
Solubility in vitamins	Soluble in vitamins	Insoluble in vitamins
Common Examples	Palmitic acid, stearic acid, lauric acid, arachidic acid, and myristic acid	Oleic acid, linoleic acid, linolenic acid, palmitoleic acid, and arachidonic acid

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