On food and cooking the science and lore of the kitchen ( PDFDrive ) 1166
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varietiesofcornwhoseseedscontainlittleor
no amylose and are nearly all amylopectin,
which doesn’t form networks as readily as
amylose. Waxy starches therefore make
sauces and gels that resist congealing and
separationintoafirmsolidphaseandwatery
residue, a problem to which high-amylose
starchesareprone.
Ingredientmanufacturersalsousephysical
andchemicaltreatmentstomodifythestarch
moleculesfromstandardplantvarieties.They
precookanddrystarchesinvariouswaysto
producepowdersorgranulesthatreadily
absorbcoldwaterordisperseinandthicken
liquidswithoutrequiringcooking.Andthey
alterthemwithchemicals—cross-linking
chainstoeachother,oroxidizingthem,or
substitutingfat-solublesidegroupsalongthe
chain—tomakethemlessproneto
breakdownduringcooking,tomakethem
moreeffectiveemulsionstabilizers,andto
givethemotherqualitiesthat“native”
starchesdon’tnormallyhave.Suchstarches
arelistedoningredientlabelsas“modified
starch.”
TheInfluenceofOther
IngredientsonStarchSauces
Flavorings:Salt,Sugar,AcidStarchand
waterarethebasisforasauce’sstructure,and
mostotheringredientshaveonlysecondary
effectsonthatstructure.Salt,acid,andsugar
arefrequentlyaddedfortheircontributionsto
flavor.Saltslightlylowersthegelation
temperatureofstarch,whilesugarsincrease
it.Acidsintheformofwineorvinegar
encouragethefragmentationofstarchchains
intomuchshorterlengths,sothatstarch
granulesgelateanddisintegrateatlower
temperatures,andthefinalproductisless
viscousforagivenamountofstarch.Root
starchesarenoticeablyaffectedbymoderate
acidity(apHlowerthan5),whilegrain
