On food and cooking the science and lore of the kitchen ( PDFDrive ) 1402
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digestive enzymes, weakens cell walls, and
begins the process of converting starch into
fermentablesugars.Theshadingindicatesthe
progress of cell-wall weakening and starch
digestion. Malting is stopped when the
growing shoot just reaches the tip of the
kernel.
BitternessandAromaHopsprovidetwo
differentelements:bitternessfromphenolic
“alphaacids”intheirresins,andaromafrom
theiressentialoil.Somehopvarieties
contributeadependablelevelofbitterness,
whileothersareprizedfortheiraroma.The
importantbitteringcompoundsarethealpha
acidshumuloneandlupulone.Intheirnative
formthey’renotverysolubleinwater,but
prolongedboilingtransformstheminto
solublestructuresthatflavorthebeer
effectively.(Brewerssometimesusehop
extractsthathavebeenpretreatedtoproduce
themoresolublealphaacids.)Becauseboiling
evaporatesawaymanyofthevolatilearoma
compounds,anotherdoseofhopsis
sometimesaddedtothebrewaftertheboiling,
specificallytoaddaroma.Thearomaof
ordinaryhopsischaracterizedbytheterpene
myrcene,whichisalsofoundinbayleafand
verbena,andiswoodyandresinous.“Noble”
hopvarietiesaredominatedbyhumulene,
whichismoredelicate,andoftencontainpine
andcitrusnotesfromotherterpenes(pinene,
limonene,citral).TheAmericanvariety
“Cascades”hasadistinctivefloweriness(due
tolinaloolandgeraniol).
BrewingBeer
Thebrewingofbeertakesplaceinseveral
stages.
Mashing:groundbarleymaltissoakedin
hotwater.Thisrevivesthebarley
enzymes,whichbreakstarchintosugar
chainsandsugars,andproteinintoamino
