Malcolm G Stephen 2003 Fats and Oils © Malcolm G Stephen 2004.
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Transcript of Malcolm G Stephen 2003 Fats and Oils © Malcolm G Stephen 2004.
Malcolm G Stephen 2003
Fats and Oils
© Malcolm G Stephen 2004
Malcolm G Stephen 2003
Fats and Oils
Naturally occurring
Animal fat
Vegetable oil
Marine oil
lardsuet
sunflower oilcoconut oil
cod liver oilwhale oil
Malcolm G Stephen 2003
Fats and Oils
glycerol
Systematic name is propane-1,2,3-triol
Fats and oils are built from an alcohol with three -O-H groups.
Malcolm G Stephen 2003
Fats and Oils
Stearic acid
Systematic name is octadecanoic acid
The other components of fat molecules are carboxylic acidssuch as
Malcolm G Stephen 2003
Fats and Oils
Fats and oils are ESTERS of glycerol and long chain carboxylic acids
Malcolm G Stephen 2003
Fats and Oils
The structural formula shown above suggests that the fat
molecule is shaped like an E, but the molecule is actuallyshaped more like this-
Removal of water in the condensation reaction gives a fat-
Malcolm G Stephen 2003
Fats and OilsFats are mainly built from carboxylic acids with C-C single bonds.
Stearic acid in beef fat
notice that with only C-C bonds the molecule is “straight”
Malcolm G Stephen 2003
Fats and OilsOils have some C=C bonds in the carboxylic acids from which they are made.
Oleic acid in olive oil
notice that the shape of the molecule is distorted by the C=C bond
Malcolm G Stephen 2003
Fats and Oils
Oil
Fat
Double bonds in oil make the molecule less compact.Less tightly packed molecules make oils liquid.
Fat molecules pack together tightly, making fats solid at room temperature.
Malcolm G Stephen 2003
Fats and OilsConverting C=C bonds to C-C will change oils into fats.This is done by addition of hydrogen (hydrogenation) using a nickel catalyst.
in oil
in fat
Malcolm G Stephen 2003
Fats and Oils
© Malcolm G Stephen 2004