On food and cooking the science and lore of the kitchen ( PDFDrive ) 1269
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countriesthatarethemajorconsumers.Sugar
beets,ontheotherhand,areatemperatecrop,
grown mainly in Europe and NorthAmerica,
so they are processed all the way to refined
sugarinasinglefactory.Harvestedsugarcane
is very perishable and must be processed
immediately; sugar beets may be stored for
weeks to months before they are processed
intosugar.
Sugarproductionrequirestwobasickinds
ofwork:crushingthecanetocollectthejuice,
andthenboilingoffthejuice’swater.The
crushingishardphysicallabor,andthe
boilingrequireslargeamountsofheat.Inthe
Caribbean,theseneedswerefilledbyslave
laboranddeforestation.Three19th-century
innovationshelpedmakesugaralesscostly
pleasure:theapplicationofsteampowerto
thecrushing;thevacuumpan,whichboilsthe
syrupatreducedpressureandsoatalower,
gentlertemperature;andthemultiple
evaporator,whichrecyclestheheatofone
evaporationstagetoheatthenext.
Theinitialclarificationofcaneandbeet
juiceisnowaccomplishedwithouteggsor
blood;heatandlimearegenerallyusedto
coagulateandremoveproteinsandother
impurities.Ratherthanwaitingforgravityto
drawoffmolasses,refinersusecentrifuges,
whichspintherawsugarasasaladspinner
spinsgreens,forcingtheliquidoffthecrystals
inminutesratherthanweeks.Thesucroseis
whitenedbythetechniqueofdecolorization,
inwhichgranularcarbon—amateriallike
activatedcharcoalthatcanabsorbundesirable
moleculesonitslargesurfacearea—isadded
tothecentrifuged,redissolvedsugar.Afterit
absorbsthelastremainingimpurities,the
charcoalisfilteredout.Thefinal
crystallizationprocessiscarefullycontrolled
togiveindividualsugarcrystalsofuniform
size.Ourtablesugarisanastonishinglypure
99.85%sucrose.
