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On food and cooking the science and lore of the kitchen ( PDFDrive ) 371

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andwhenit’sold.
TheHealthfulness
ofFishOils

WhyshouldfishandnotAngussteersprovide
thehighlyunsaturatedfatsthatturnouttobe
goodforus?Becauseoceanicwatersare
colderthanpasturesandbarns,andmostfish
arecold-blooded.Throwabeefsteakinthe
oceananditcongeals;itscellsaredesignedto
operateattheanimal’susualbody
temperature,around100ºF/40ºC.Thecell
membranesandenergystoresofoceanfish
andtheplanktontheyeatmustremainfluid
andworkableattemperaturesthatapproach
32ºF/0ºC.Theirfattyacidsarethereforevery
longandirregularinstructure(p.801),and
don’tsolidifyintoorderlycrystalsuntilthe
temperaturegetsverylowindeed.
ThePerishabilityofFish
andShellfish


Thecoldaquaticenvironmentisalso
responsibleforthenotorioustendencyoffish
andshellfishtospoilfasterthanothermeats.
Thecoldhastwodifferenteffects.First,it
requiresfishtorelyonthehighlyunsaturated
fattyacidsthatremainfluidatlow
temperatures:andthesemoleculesarehighly
susceptibletobeingbrokenbyoxygeninto


stale-smelling,cardboardyfragments.More
importantly,coldwaterrequiresfishtohave
enzymesthatworkwellinthecold,andthe
bacteriathatliveinandonthefishalsothrive
atlowtemperatures.Theenzymesand
bacteriatypicalofourwarm-bloodedmeat
animalsnormallyworkat100ºF/40ºC,andare
slowedtoacrawlinarefrigeratorat40ºF/5ºC.
Butthesamerefrigeratorfeelsperfectly
balmytodeep-waterfishenzymesand
spoilagebacteria.Andamongfishes,coldwaterspecies,especiallyfattyones,spoil
fasterthantropicalones.Whererefrigerated
beefwillkeepandevenimproveforweeks,



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