The food lab better home cooking through science ( PDFDrive ) 470

offood—orliquid—atastabletemperature:thebeercooler.
Here’showitworks:Abeercoolercankeepthingscool
because it is a two-walled plastic chamber with air space
between the walls. The air space acts as an insulator,
preventing thermal energy from the outside from reaching
thecoldfoodontheinside.Ofcourse,insulatorsworkboth
ways—thecoolerisjustasgoodatkeepingthermalenergy
ontheinsidefromescapingtotheoutside.Onceyourealize
thatabeercoolerisjustasgoodatkeepinghotthingshotas
it is at keeping cold things cold, the rest is easy: Fill your
cooler with water just a couple degrees higher than the
temperatureyou’dliketocookyourfoodat(toaccountfor
temperature loss when you add the cold food), seal your
foodinazipper-lockfreezerbag,dropitin,andcloseyour
cooler.Leavethefoodthereuntilitiscooked.It’sassimple
asthat.


ButWhatAbouttheVacuum?
Surely vacuum-sealing the food is an essential step in
effectivesous-videcooking?Asitturnsout,notreally.The
main reason to vacuum-seal food is that any air bubbles
trapped inside the plastic bag can act as an insulator,
preventing the food from cooking evenly.As long as you
cangetallthebubblesoutofyourbag,there’snoreasonit
shouldn’tworkjustaswellasabagsealedwithavacuumsealerandthere’saneasywaytodojustthat.Thistechnique
was demonstrated for me by DaveArnold, an instructor at
theFrenchCulinaryInstituteandcontributortotheCooking
Issuesblog(www.cookingissues.com):
1. Place your food inside a zipper-lock freezer bag and
sealit,leavingthelastinchunsealed.

2.Holdingontothebag,slowlyloweritintoalargepot,
cooler,orsinkfulofwater,usingyourhandstorelease