Page 80 - Statistics presented by Dr. Sara Ismail Aborass

9/8/2023

Fats and oils in saponifiable lipids

The main difference between saponifiable fats and oils is that fats are
composed of high amounts of saturated fatty acids which will take a
solid form at room temperature whereas oils are composed of mainly
unsaturated fatty acids which will take a liquid form at room temperature.

Generally, as chains become longer and/or more saturated, triglyceride is more likely to
be a fat (solid at room temp)
As chains become shorter and/or more unsaturated, triglyceride is more likely to be an
oil (liquid at room temp)
C- according to the degree of un-saturation of the fatty acid component(Oils)
Drying oils (large number of unsaturation)
Non-drying oils (least number of unsaturation)
Semi-drying oils (intermediate number of unsaturation)

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Drying oils

• Contain mainly glycerides of unsaturated fatty acids (E.g. Linoleic acid,
linolenic acid), they harden and form a solid film under the influence of
atmospheric oxygen (liquid + O2 solid)

• Linseed oil - fish and marine oils
Non-drying oils

• Contain least amount of glycerides of unsaturated fatty acid.
• Unsaturated fatty acids contain mainly one double bond only (oleic acid)
• They do not change on exposure to the atmosphere
• Olive oil – castor oil – almond oil – coconut oil

Semi-drying oils
• Intermediate degree of unsaturation
• Cotton seed oil – sesame oil

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