7 Fats by 0ww0RNy

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									FATS
Fats and oils are chemically similar, but differ
in physical states.




                      1
Fats   : - found in animals
         - solid in room temperature
         - butter and tallow (types of fat)

Oil    : - fats from plants
         - liquid in room temperature
         - palm oil, coconut oil, sunflower oil

- Fats and oil are mixtures of different esters.
- Fats are formed from 3 molecules of long-
  chain carboxylic acids called fatty acids
  with 1 molecules of alcohol called glycerol.




                       2
     O
     ║        Fatty acids
OH ― C ― R1   - R1 , R2 , R3 contains
                12 to 18 carbon
     O          atoms per molecule
     ║        - R1 , R2 , R3 are three
OH ― C ― R2     alkyl groups which
                may be the same or
     O
     ║          different
OH ― C ― R3   - group: carboxilic acid



    H
    │
H ― C ― OH
    │         Glycerol
H ― C ― OH    - propane-1,2,3-triol
    │
              - group: alcohol
H ― C ― OH
    │
    H




              3
Formation of a fat molecule
                                 O
                                 ║
               Break up
    H                       OH ― C ― R1
               and rejoin
    │
H ― C ― OH        +              O
    │                            ║
               Break up
H ― C ― OH     and rejoin
                            OH ― C ― R2
    │
H ― C ― OH                       O
    │          Break up          ║
    H          and rejoin   OH ― C ― R3



              H       O
              │       ║
          H ― C ― O ― C ― R1
              │
              │       O
              │       ║
          H ― C ― O ― C ― R2     + 3H2O
              │
              │       O
              │       ║
          H ― C ― O ― C ― R3
              │
              H

                      4
Importance of fats and oils
- energy
- nutrients
- thermal insulation
- protection to internal organ

[Text book: Figure 2.34 pg. 86]

Saturated and unsaturated fats
- Fat or oil molecules is affected by parent fatty
  acids.
- Fatty acids can be differentiated in two ways;
    i. the length of the carbon chains
        (12 to 18 carbon atoms)
    ii. saturated or unsaturated

Saturated fatty acid
- All carbon atoms joined together by
  carbon-carbon single covalent bond.
- example:
    Lauric acid      (12 carbon atoms)
    Palmitic acid    (16 carbon atoms)
    Stearic acid     (18 carbon atoms)
                      5
Unsaturated fatty acid
- The carbon chain has one or more
  carbon-carbon double covalent bond.

Example:
i. Oleic acid: monounsaturated fatty acid
   (one carbon-carbon double bond)-
  [no of C = 18, DB = 9&10]

ii. Linoleic acid: polyunsaturated fatty acid
    (two carbon-carbon double bond)
  [no. of C = 18, DB = 9&10, 12&13]

iii. Linolenic acid: polyunsaturated fatty acid
    (three carbon-carbon dauble bond)
    [no. of C = 18, DB = 9&10, 12&13,
                         15&16]




                      6
Saturated Fats
- Fats contain esters of glycerol and saturated
  fatty acids.

 - Example:
 i. Tristearin    ( glycerol + stearic acid)
ii. Tripalmitin   (glycerol + palmitic acid)

Tristearin

      H       O
      │       ║
  H ― C ― O ― C ― (CH2)16 — CH3
      │
      │       O
      │       ║
  H ― C ― O ― C ― (CH2)16 — CH3
      │
      │       O
      │       ║
  H ― C ― O ― C ― (CH2)16 — CH3
      │
      H


                      7
Tripalmitin


     H       O
     │       ║
 H ― C ― O ― C ― (CH2)14 — CH3
     │
     │       O
     │       ║
 H ― C ― O ― C ― (CH2)14 — CH3
     │
     │       O
     │       ║
 H ― C ― O ― C ― (CH2)14 — CH3
     │
     H


- Animal fats have large proportions of
  saturated fats.
- They have high melting point and solids at
  room temperature.



                     8
Unsaturated Fats
  - Fats contain esters of glycerol and
    unsaturated fatty acids.

 Example:
   i. Triolein      (glycerol + oleic acid)

     H       O
     │       ║
 H ― C ― O ― C ― (CH2)7 — CH ═ CH — (CH2)7 — CH3
     │
     │       O
     │       ║
 H ― C ― O ― C ― (CH2)7 — CH ═ CH — (CH2)7 — CH3
     │
     │       O
     │       ║
 H ― C ― O ― C ― (CH2)7 — CH ═ CH — (CH2)7 — CH3
     │
     H

   - Plant or vegetable oils contain a large
     proportions of unsaturated fats.
   - They have lower melting points and are
     liquids at room tempoerature.
                         9
Converted unsaturated fats to saturated fats
- Unsaturated fats can be converted into
  saturated fats by process called catalytic
  hydrogenation.

The hydrogenation process is carried out by
bubbling hydrogen gas through hot, liquid
oil in the presence of fine particles of nickel
catalyst.




                     10
Effect of fats on health
- Saturated fats (animal oil) will raise the level
  of cholesterol.
- Cholesterol causes fatty deposites or the wall
  of veins or arteries.
- Blood circulation is restricted and will raise
  the blood presure
- Arteriosclerosis, can result in heart attack.
- Unsaturated fats (plant oil) do not contain
  cholesterol. Do not cause cardiovascular
  problems.
                      11
   Uses of palm oil
   - Has many advantages.
   - A cheaper, better and healthier oil.

   [Text book: Figure 2.36 pg. 90]

Prepared by;
Kamal Ariffin Bin Saaim
SMKDBL
http://kemhawk.webs.com




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