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On food and cooking the science and lore of the kitchen ( PDFDrive ) 1481

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temperatureofthefoodasawholequickly
rises.
Metalfoilandutensilscanbeputinthe
microwaveovenwithmoistfoodswithout
causingproblems,providedthey’re
reasonablylargeandkeptsomedistancefrom
thewallsandeachothertopreventarcing.
Finemetallicdecorationonchinawillspark
andsufferdamage.Foilisusefulforpartly
shieldingsomefoodsfromtheradiation,the
thinedgesoffishfillets,forexample.
Microwaveovensarearecentinvention.In
1945Dr.PercySpencer,ascientistworking
forRaytheoninWaltham,Massachusetts,
filedapatentfortheuseofmicrowavesin
cookingafterhehadsuccessfullypoppedcorn
withthem.Thiskindofradiationhadalready
beenusedindiathermy,ordeepheat
treatmentforpatientswitharthritis,aswellas
incommunicationsandnavigation.
Microwaveovensbecameapopularappliance
inthe1970s.


Advantages
and
Disadvantages
of
Microwaves Microwave radiation has one
great advantage over infrared: the fact that it
cooks food much faster. Microwaves can


penetratefoodtoadepthofaboutaninch/2.5
cm, while infrared energy is almost entirely
absorbed at the surface. Because heat
radiationcantraveltothecenteroffoodsonly
bytheslowprocessofconduction,it’seasily
beatenbymicrowaves,withtheirsubstantially
deeper reach. This reach, along with the
microwaves’ concentration on heating the
foodandnotitssurroundings,resultsinavery
efficientuseofenergy.
Microwavecookinghasseveral
disadvantages.Oneisthat,inthecaseof
meats,speedyheatingcancausegreaterfluid
lossandsoadriertexture,andmakesitmore
difficulttocontroldoneness.Thiscanbe
partlyovercomebypulsingtheovenonand
offtoslowtheheating.Anotherproblemis
thatmicrowavescannotbrownmanyfoods



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