Lard
This fat is obtained from cutaneous adipose tissue of pork. Its fatty acid
composition depends on the diet. As an example, linoleic acid content is low
(about 2%) when pork is fed with rice but high (about 30%) when soja is used as
main food.
The dressed weight of pigs contains about 30% fat but very fat pigs can contain
up to 50% fatty matter. The world production of lard is about 7.4 million tons per
year (2004-2005).
Beef tallow
This fat is extracted from beef adipose tissue. By definition, tallow is fat
rendered primarily from cattle, but it also is fat from sheep and goats. Its fatty acid composition
depends on the tissue location more than on the food ingested. As lipids are
partially hydrogenated in the rumen, 6-8% elaidic acid and traces of conjugated
dienes and trienes are detected in beef tallow.
The proportion of fat in the dressed weight varies from 8% up to 25% in fat beef.
The world production of beef tallow was about 8.2 million tons in 2004-05
(about 7% of the global fats and oils production).
Accounts of the use of tallow in soapmaking extend back thousands of years
(traditional soap is made of about 85% tallow and 15% coconut or palm kernel
oil). Tallow was also a part of the world's first surviving art since
prehistoric cave paintings were most probably made using animal tallow mixed
with pigments.
While amounts of tallow used for edible purposes in human show slight decline,
its use is increasing in animal feeds.
Inedible tallow gives numerous and various derivatives from plastics, lotions,
soaps and detergents, tires, candles, paints and varnishes, lubricants and
several pharmaceuticals. Tallow is an important factor in the global fatty acids
market. These fatty acids play an important role in the formulation of
pesticides, herbicides, emulsifiers, and dispersing agents. Several derivatives
are produced from tallow : fatty alcohols, amines, amides, esters and
glycerol.
Bone fats
This fat is found in bone marrow (about 95% of the dry weight) and is separated
during gelatin processing. As phospholipids are present, bone fats are more
unsaturated than the other animal fats. Odd carbon number and branched fatty
acids are found as in tallow.
Poultry fats
They are produced from various bird species and their fatty acid composition
depends largely on the food ingested. Chicken fat is characterized by a
relatively high proportion (about 10%) of palmitoleic (16:1 n-9) and linoleic
acid (18:2 n-6) (about 25%). Fatty liver of duck or goose is characterized by
triglycerides rich in oleic acid (about 60%) and containing moderate amounts of
palmitic and stearic acids (20 and 15%, respectively).
The average fatty acid compositions (weight percent) of these important fat
products are given in the table below:
|
Lard |
Tallow |
Bone |
Poultry |
|
| 14:0 |
1-2 |
3-4 |
1.8-2.5 |
0.2-1.3 |
| 15:0 |
- |
<0.6 |
<1 |
- |
| 16:0 |
22-26 |
23-27 |
23-26 |
22-28 |
| 16:1 |
1.5-3 |
2-4 |
2-4 |
2-9 |
| 17:0 |
<0.5 |
1-1.5 |
1-1.5 |
- |
| 17:1 |
<0.4 |
<1 |
<1 |
- |
| 18:0 |
13-18 |
15-23 |
15-18 |
6-11 |
| 18:1 |
39-45 |
36-43 |
41-45 |
37-53 |
| 18:2 |
8-15 |
1.5-4 |
2-5 |
9-25 |
| 18:3 |
0.5-1.5 |
0.3-1 |
0.5-2 |
<2 |
| 20:0 |
<0.3 |
<0.2 |
- |
- |
| 20:1 |
<1.3 |
<0.5 |
<1 |
- |
| isoC15-18 |
<0.3 |
1-2.5 |
0.6-2 |
- |
To get information on the triacylglycerol structure of these fats :
