On food and cooking the science and lore of the kitchen ( PDFDrive ) 1292
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allowthesyruptocoolbeforeinitiating
crystallization
avoidagitatingthesyrupwhileitcools
whenthesyrupiscool,agitate
continuouslyandvigorouslyforaslong
asthesyrupisworkable
PreventingCrystalFormation:Making
SugarintoaGlassCandymakersproducean
entirelydifferentstructureandtexturewhen
theycoolasyrupsorapidlythatthesugar
moleculesstopmovingbeforetheyhavea
chancetoformanycrystalsatall.Thisishow
transparenthardcandiesaremade.Ifthe
watercontentofthecookedsyrupisjust1or
2%,thenit’sessentiallymoltensugarwitha
traceofwaterdispersedinit.Thesyrupis
veryviscous,andifitcoolsquickly,the
sucrosemoleculesneverhaveachanceto
settleintoorderlycrystals.Instead,theyjust
setinplaceinadisorganizedmass.Suchan
amorphous,noncrystallinematerialiscalleda
glass.Ordinarywindowandtableglassisa
noncrystallineversionofsilicondioxide.Like
thismineralglass,sugarglassisbrittleand
transparent(andoftenstandsinforitsharder
andmoredangerouscousininthemoviesand
onstage!).Glassesaretransparentbecause
individualsugarmoleculesaretoosmallto
deflectlightwhenthey’rerandomlyarranged.
Crystallinesolidsappearopaquebecauseeven
tinycrystalsaresolidmassesofmany
molecules,andtheirsurfacesarebigenough
todeflectlight.
Limiting Crystal Growth with Interfering
AgentsInpractice,it’snoteasytocontrolor
prevent the crystallization of pure sucrose
syrups,andcandymakershavelongreliedon
other ingredients that interfere with and
therefore limit crystal formation and growth.
Theseinterferingagentshelpthecookprepare
clear noncrystalline hard candies and finetextured creams, fudges, and other soft
