Background
Information
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What is Latex?
Latex is the protective fluid contained in tissue beneath the
bark of the rubber tree, Hevea brasiliensis. In its purest form,
latex is a milky white liquid composed of rubber particles dispersed
in water that can be tapped from the trunks of mature rubber trees.
Latex contains hundreds of proteins, including enzymes that are
involved in the biosynthesis of the rubber molecules.
Processing
Most natural rubber is produced in Africa and South Asia. Trees
are tapped for latex, by cutting a spiral groove in the bark and
placing a spout and collection cup, containing ammonia or some
other preservative, at the bottom.
Initially, the rubber had to be solidified within 24 hours to
stop bacterial spoilage, this was known as crepe, but in the 1920's
it was discovered that the addition of ammonia could preserve the
latex.
By centrifugation (rotating in order to separate liquids from
solids by the action of centrifugal force) a concentrated product
is obtained.
Additional chemicals, such as accelerators, and antioxidants are
added for strength, stretch and durability.
Natural rubber is derived from latex, and should be distinguished
from synthetic rubber, derived from petrochemicals.
History
Latex is believed to have originated more than a hundred years
ago. The tree originated from Brazil (hence its name - Hevea brasiliensis),
and latex was originally gathered from wild trees in the jungles
of Brazil in the 1870's. By 1890, Britain had introduced rubber
plantations in Malaysia (with the help of Kew gardens and the Singapore
Botanical Gardens) and was harvesting latex.
Africa and Sudan now produces 60 per cent of the world production.
The African industry is overseen by UAGAP, the Union of African Gum
Producing Countries whose members include Sudan, Chad, Niger and Nigeria.
UAGAP aims include improved quality control methods including greater
interaction with farmers and establishment of buffer stocks for periods
of lean production such as droughts.
Nigeria produces the highest quality gums,
such as Nigerian No 1, which are derived from wild trees. One
of Nigeria’s major domestic
players is Tadacon.
The largest buyer of gum in the first half of
the century was the UK. There was a time when London was synonymous
in the trade with
gum product exports. Subsequently, France began using gums, then
America.
Today, the US is the largest consumer of gum-based products, used
mainly in foods.
The value of gum trade exports has shrunk since
1967 when a total of 40,000 tonnes of Arabic gum were exported, worth £40 million,
while 4,000 tonnes of Karaya gum and 300 tonnes of Tragacanth gum were
exported both worth £5 million.
This levelled out in the 1980’s and has remained constant
ever since. By 1997 exports of Arabic gum total 25,000 tonnes worth £34
million with 3,000 tonnes (£4.5 million) and 150 tonnes (£2.5
million) for Karaya and Tragacanth gum respectively.
Types & Uses
Natural gums include Gum Arabic (Africa), Gum Karaya (India/Africa),
Gum Acacia, Gum Tragacanth (Iran) and Gum Ghatti, which are used
in the foods and pharmaceutical industries. Gums are used as emulsifiers
and stabilisers.
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Health Foods
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Global demand for healthier food additives,
including gums, has grown in recent years as the global food
industry's use of fats in food declines.
In particular, economic development in Asia and central
America has resulted in massive demand for better processed
food. Trends in the industry include the removal of fats,
calories and sodium from foods and replacing them with
nutritional ingredients. The rapid growth in the gums sector
is being largely driven by consumer demand for low-fat
and no-fat products. This means replacing oil with water
and using thickeners to provide the same taste and texture
normally supplied by fat.
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Labelling
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Paper and cloth, with users finding Gum Arabic
much more economical than synthetic adhesives. One of the
biggest advantages of the product is that, even after it
hardens, it remains water-soluble. It is therefore ideal
for use with fabric labels, which must come off at the time
of tailoring.
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Soft drinks
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All soft drinks are made with Gum Arabic,
which is an excellent stabiliser, is used for oil and water
entrapment and has a good "mouth feel".
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Chewing gum
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Chewing gum is nothing but Gum Arabic, sugar
and added flavours.
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Fireworks
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Used for binding fireworks
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Characteristics
In low concentrations, these gums form a `solution'; in higher concentrations,
a `slurry'; and at the top of the thickness scale, they form a `gel'.
The whiter varieties are more valuable, while the red and amber
ones fetch a lesser price. The black ones are at the bottom of the
scale.
Before it is processed, Gum Arabic comes in the form of lumps, crystals
and a fine crystalline powder which goes through a mesh. The product
has to be manually sorted out and segregated according to size, colour
and purity.
Gum Arabic is soluble in water, Gum Karaya is not soluble
in water.
What is the International Rubber Study Group (IRSG)
The IRSG was founded in 1944 to provide a forum for
the discussion of matters affecting the supply of and demand for
natural rubber;
it covers all aspects of the world rubber industry, including the
manufacture of products, trade in raw materials and products, shipping,
marketing and distribution. It collects and disseminates statistical
data and undertakes economic and statistical studies on specific
aspects.
What is the Association of Natural Rubber Producing Countries (ANRPC)
The ANRPC was founded in 1970 to promote the overall interests of
natural rubber; membership is open to the governments of countries
producing natural rubber. Its objectives are to bring about co-ordination
in production and marketing, to promote technical co-operation among
its member countries, and to bring about remunerative and stable
prices for natural rubber.
The ANRPC performs studies on the world rubber position, examines
short- and long-term problems and promotes research and development.
Its Secretariat is in Kuala Lumpur.
What is the International Natural Rubber Organization (INRO)
INRO was established in 1980 to operate the International Natural
Rubber Agreement the main purpose of which is to stabilize the price
of natural rubber by buying for and selling from a buffer stock.
INRO's terms of reference also cover measures to improve the status
of natural rubber by encouraging research and other activities. Its
headquarters are in Kuala Lumpur. At a meeting in September 1999
the participating nations agreed to terminate the Agreement and to
liquidate the buffer stock. This operation is now taking place.