On food and cooking the science and lore of the kitchen ( PDFDrive ) 1452
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essentialrolesofmicrobesandoxygeninthe
traditionalOrléansprocess(p.773).Modern
methodsforgrowingbaker’syeastand
producingpenicillinwereadaptedtovinegar
manufactureafterWorldWarII,andnow
producefinishedvinegarinadayortwo.
TheVirtuesofAceticAcid
Aceticacidcontributestwodifferentflavor
elementstofoods.Oneisitsacidityonthe
tongue,andtheotherisitscharacteristic
aromainthenose,whichcanintensifytoa
kindofstartlingpungency,particularlywhen
thevinegarisheated.Thevinegarmolecule
canexistintwoforms:astheintactmolecule,
andbrokenintoitsmainportionandafree
hydrogenion.Thehydrogeniongivesthe
mainimpressionofacidity,whileonlythe
intactmoleculeisvolatileandcanescape
fromthevinegarorfood,travelthroughthe
air,andreachthenose.Boththeintactand
“dissociated”formscoexistsidebyside,in
proportionsthataredeterminedbytheir
chemicalsurroundings.Ifthefoodisalready
acidic—thankstothepresenceoftartaric
acidinwinevinegar,forexample—thenless
oftheaceticaciddissociates,moreisintact
andvolatile,andthevinegararomais
stronger.
Aceticacidisanespeciallyeffective
preservingagent.Asolutionasweakas0.1%
—theequivalentofateaspoonofstandardstrengthvinegarinacupofwater/5mlin250
ml—willinhibitthegrowthofmany
microbes.
Aceticacidhasahigherboilingpointthan
water,236ºF/118ºC.Thismeansthatvinegar
willgetmoreconcentratedifit’sboiled.
Becausehalfofitsmoleculeismorefat-like
thanwater-like,itisabettersolventthan
waterformanychemicalrelativesoffats,
includingthearomacompoundsinherbsand
spices.Thisiswhycooksflavorvinegarsby
