On food and cooking the science and lore of the kitchen ( PDFDrive ) 1463

Caramelization

Thesimplestbrowningreactionisthe
caramelizationofsugar,andit’snotsimpleat
all(p.656).Whenweheatplaintablesugar,
essentiallyjustmoleculesofsucrose,itfirst
meltsintoathicksyrup,thenslowlychanges
color,becominglightyellowand
progressivelydeepeningtoadarkbrown.At
thesametime,itsflavor,initiallysweetand
odorless,developsacidity,somebitterness,
andaricharoma.Thechemicalreactions
involvedinthistransformationaremany,and
theyresultintheformationofhundredsof
differentreactionproducts,amongthemsour
organicacids,sweetandbitterderivatives,
manyfragrantvolatilemolecules,andbrowncoloredpolymers.It’saremarkablechange,
andafortunateone:itcontributestothe
pleasuresofmanycandiesandothersweets.
TheMaillardReactions


Evenmorefortunateandcomplexarethe
reactionsresponsibleforthecookedcolorand
flavorofbreadcrusts,chocolate,coffeebeans,
darkbeers,androastedmeats,allfoodsthat
arenotprimarilysugar.Theseareknownas
theMaillardreactions,afterLouisCamille
Maillard,aFrenchphysician,whodiscovered
anddescribedthemaround1910.The
sequencebeginswiththereactionofa

carbohydratemolecule(afreesugarorone
boundupinstarch;glucoseandfructoseare
morereactivethantablesugar)andanamino
acid(freeorpartofaproteinchain).An
unstableintermediatestructureisformed,and
thisthenundergoesfurtherchanges,
producinghundredsofdifferentby-products.
Again,abrowncolorationandfull,intense
flavorresult.Maillardflavorsaremore
complexandmeatythancaramelizedflavors,
becausetheinvolvementoftheaminoacids
addsnitrogenandsulfuratomstothemixof
carbon,hydrogen,andoxygen,andproduces