On food and cooking the science and lore of the kitchen ( PDFDrive ) 1279
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andaviscoussyrup.Afewyearslater,he
discoveredthatmaltedbarleyhadthesame
effectastheacid(andtherebylaidthe
foundationsforascientificunderstandingof
beerbrewing).Wenowknowthatstarch
consistsoflongchainsofglucosemolecules,
andthatbothacidsandcertainplant,animal,
andmicrobialenzymeswillbreaktheselong
chainsdownintosmallerpiecesand
eventuallyintoindividualglucosemolecules.
Thesugarsmakethesyrupsweet,andthe
remainingfragmentsofglucosechainsgive
thesolutionathick,viscousconsistency.In
theUnitedStates,theacidtechniquewasused
toproducesyrupfrompotatostarchinthe
1840s,andfromcornstarchbeginninginthe
1860s.
High-Fructose Corn Syrups The 1960s
brought the invention of fructose syrups.
Thesestartoutasplaincornorpotatosyrups,
but an additional enzyme process converts
some of the glucose sugars into fructose,
whichismuchsweeterandthereforegivesthe
syrupsahighersweeteningpower.Thesolids
in standard high-fructose corn syrup are
around 53% glucose and 42% fructose, and
provide the same sweetness as the syrup’s
equivalent weight in table sugar. Because
high-fructose syrups are relatively cheap,
soft-drink manufacturers began to replace
cane and beet sugars with them in the 1980s,
and Americans began to consume more corn
syrups than cane and beet sugar. Today
they’re a very important sweetener in food
manufacturing.
Making Corn Syrups To make corn syrups,
manufacturers extract starch granules from
thekernelsofcommondentcorn(p.477),and
then treat them with acid and/or with
microbialormaltenzymestodevelopasweet
syrup that is then clarified, decolorized, and
evaporated to the desired concentration.
