Like all plant-based food products, sugar starts on the
farm. Sugar cane is a
grass crop that has been cultivated since the time of Alexander the
Great.
When the cane matures, it flowers at the top of the stalk signaling it
is ready
for harvest. In most instances, the fields are burnt as a way of
stripping the
plant of excess leaves. The cane is then harvested by cutting the stalks
either
mechanically or by hand. The harvested stalks are then delivered to a
sugar
mill where the cane is crushed by conveying it through a series of
rollers to
remove the juice.
This initial juice is about 10% sucrose, while the rest
is water. In order to re-
move field impurities from the juice, it is clarified either by the
addition of
natural lime or a flocculent. The cleaned juice is then concentrated by
evapor-
ating the excess water through the use of heat under vacuum conditions.
This
creates a super saturation solution which, when "seeded" with sugar
crystals,
starts the crystallization process.
The molasses-laden crystals are then placed into a
centrifuge where the
molasses is separated from the sucrose by the centrifugal force of the
spinning
centrifuge. The crystals produced at this stage are considered raw
sugar. Raw
sugar by definition is unfit for direct human consumption due to the
lack of
proper hygiene and food-grade handling practices. The crystals are of a
dark
brown and gray complexion and have a number of impurities or sediment
contained within them. Raw sugar, therefore, is then sent to a sugar
refinery
for further processing.
At the refinery the raw sugar is mixed with a heated
solution in order to convey
it through the factory. This is called affination. The sucrose solution
then goes
through much the same process it originally went through at the mill. It
is filtered
and cleaned again, then re-crystallized and, in some instances,
re-melted and
re-crystallized again. Finally, it is decolorized by using animal bone
char or
other types of decolorizing agents that remove the natural color and any
remaining trace elements. The finished product is refined white sugar.
Go on to The Color
Black
Return to 24 February 1999 Issue
Return to Newsletters
** Fair Use Notice**
This document may contain copyrighted material, use of which has not been
specifically authorized by the copyright owners. I believe that this
not-for-profit, educational use on the Web constitutes a fair use of the
copyrighted material (as provided for in section 107 of the US Copyright
Law). If you wish to use this copyrighted material for purposes of your
own that go beyond fair use, you must obtain permission from the copyright
owner.