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me_rathee
February 27th, 2009, 01:21 PM
How Do Microwaves Cook Food?



http://www.rps.psu.edu/probing/graphics/microwave.jpg

Microwaves possess three basic characteristics:



Just as sunlight shines through a window, microwaves pass right through some materials. Materials such as glass, paper, and plastic are transparent to and generally unaffected by microwaves.
Microwaves are reflected by metal surfaces, much as a ball would bounce off a wall. The metal walls of the cooking space actually form a cavity resonator. In other words, the enclosure is designed to resonate the microwaves as they are radiated from the magnetron tube. The principle of resonance may be illustrated using sound waves. When a piano key is struck, it produces sound vibrations or sound waves. Sometimes a note is played on a piano, and an object across the room, perhaps a wineglass, can be heard vibrating and producing the same sound. This is the result of resonance. The resonating characteristics of the wineglass are the same as those of the piano string. Therefore, the wineglass is in tune, or in resonance, with the sound wave produced by the piano string. In the same way, the cooking cavity of a microwave oven is designed to be in "tune" with the resonant characteristics of the microwaves.



Metal racks are physically proportioned so as not to disrupt the energy pattern.



Microwaves penetrate and are absorbed by some substances, primarily food products.

Friction Produces the Heat That Cooks the Food

To illustrate this third characteristic, notice the cooked turkey to the right. The waves of microwave energy are cycling above and below a horizontal baseline. The half cycle below the baseline possesses negative properties, and the half cycle above the line is correspondingly positive. Basically, the effect of this wave, as it alternates between positive and negative, would be like a magnet flipping back and forth. http://www.gallawa.com/microtech/images/cooktrky.gif


All liquids and food products, such as this turkey, are made up of molecules. These molecules have positive and negative particles, so they tend to behave like microscopic magnets. As the positive half cycle of the microwave penetrates the food, the negative particles of the molecules are attracted and attempt to align themselves with this positive field of energy. Then, when the microwave energy alternates to the negative half cycle, the opposite occurs -- The negative particles are repelled and the positive particles are attracted, causing a flipping motion (actually, this reaction is the movement of the particles within each molecule, so, technically, they reverse polarity). This might be compared to a room full of people trying to run back and forth, from one side to the other. Obviously, there would be a lot of bumping, rubbing, agitation, and friction. Now, consider that the actual frequency of the RF energy used in microwave ovens is 2450 million cycles per second! Moreover, consider that within the course of one of those cycles, the molecules would actually change their direction (polarity) twice - once for the positive half-cycle and once for the negative half-cycle. This red-hot rate of vibration causes tremendous friction within the food, and - just as rubbing your hands together makes them warm - this friction produces heat. So the heat is produced directly in the food, but the food is not cooked, as is commonly believed, from the inside out. Actually, the cooking begins just beneath the outer surface and from there inward and outward, with the majority of the energy being expended in the outer layers. The rate and degree of heating depend on the depth and density of the food, as well as its ability to conduct heat. Because the microwave energy is changed to heat as soon as it is absorbed by the food, it cannot make the food radioactive or contaminated. When the microwave energy is turned off and the food is removed from the oven, there is no residual radiation remaining in the food. In this regard, a microwave oven is much like and electric light that stops glowing when it is turned off.

anilsangwan
February 27th, 2009, 02:19 PM
Bahut badhiya rathee saab... aap ne toh aankhon k saamney hi KUKKKADDD paka diya Micro mein :)

VPannu
February 27th, 2009, 04:19 PM
http://www.gallawa.com/microtech/images/cooktrky.gif
yo kukkad taattaa hove se ak ispe maakkhi haande sein? :confused::eek:

SANDEEP5
February 27th, 2009, 05:55 PM
yo kukkad taattaa hove se ak ispe maakkhi haande sein? :confused::eek:


Pannu Bhai itna taattaa to na hota jo ye laal laal se bijli chamak rhi isme, par haan maakhi jaroor nyu hi haandya kare hain.

any way good info. Thanks rathee ji.

me_rathee
February 28th, 2009, 12:14 PM
Bhaai maakhiya ka bhi jigra se.......isse taate ne to hum khaan te pehlya sochange aur maakhi pehlya e chipat rhi se

sunitahooda
March 1st, 2009, 08:18 AM
Virender is it true that Microwave cooked food is harmful to consume? I use microwave a lot, please throw some light on this too:)
Bhaai maakhiya ka bhi jigra se.......isse taate ne to hum khaan te pehlya sochange aur maakhi pehlya e chipat rhi se

trueblueindian
March 1st, 2009, 01:42 PM
Virender is it true that Microwave cooked food is harmful to consume? I use microwave a lot, please throw some light on this too:)

Yup that info will surely be usefull

deepakchoudhry
March 1st, 2009, 03:20 PM
Virender is it true that Microwave cooked food is harmful to consume? I use microwave a lot, please throw some light on this too:)


I have asked this few times as well and looked up on the internet but there are no conclusive answers.

I suppose for researchers to give any answers is too early as microwave is fairly a new technology.

Well ....better start saving money for that hospital bed, just in case.:)

rajeshchhikara
March 2nd, 2009, 09:09 AM
bhai agar aap gas pae garam karoge to food ko vo energy bahut der se

milti hai ,jo aap microwaves se in fraction of seconds main paate ho

actually every cooking have electrons based mechanism if it is from chula,gas,or microwaves.......

microwaves have high energy ....

Microwaves used in these ovens are similar to the microwaves used in radar equipment and in telephone, television and radio communications. They are in the non-ionizing range of electromagnetic radiation, which are very different from ionizing radiation. Ionizing radiation includes the dangerous X-rays, gamma rays, and cosmic rays and is extremely toxic, powerful and penetrating. But again, non-ionizing radiation is what's used for microwave ovens and cellular telephone devices.
Coming to its cooking qualities, they are convenient for cooking as they pass through glass, paper and plastic and are absorbed by food, producing heat that can reheat or cook the food. Moreover, there are no signs that microwave cooking reduces the nutritional value of food, in fact, some experts believe that microwave cooking may preserve more of the vitamins in food because it cooks food more quickly, leaving less time for the heat to break down the vitamins, and uses less water, which can leach out the vitamins.
Many people are concerned with being exposed to a microwave oven's radiation. There are studies on the effects of microwave cooking that show both positive and negative effects on food, just as there are current studies on the dangerous effects of radiation from cell phones.

sunitahooda
March 2nd, 2009, 10:17 AM
Rajesh this was the reason why i was worried, sometime back i got an e-mail which showed two plants with same growth but being watered with normal water and other one with microwaved water and the one watered with microwaved water was looking under developed and lifeless where the other one was fresh and green. Since then i've been wondering if there is some solid truth behind that mail or its just a junk chain mail?

Oon microwave mai badda araam sai...khechall ghani kum ho jaya kare:p....kum dhobrey manney paddya karein:D


Many people are concerned with being exposed to a microwave oven's radiation. There are studies on the effects of microwave cooking that show both positive and negative effects on food, just as there are current studies on the dangerous effects of radiation from cell phones.

anilsangwan
March 2nd, 2009, 12:31 PM
Bebbey.......Pedd apni isi tisi karaawe......Microwave mein ubaallll ki paani Pedd mein gairo toh pedd underdeveloped nahi.... fukkk jaaga thoddey dina mein... :D :D :D


Rajesh this was the reason why i was worried, sometime back i got an e-mail which showed two plants with same growth but being watered with normal water and other one with microwaved water and the one watered with microwaved water was looking under developed and lifeless where the other one was fresh and green.

sunitahooda
March 2nd, 2009, 12:56 PM
ताता पाणी ना था बस ताता कर कै सीला करे पाछे गेरया था:o
Bebbey.......Pedd apni isi tisi karaawe......Microwave mein ubaallll ki paani Pedd mein gairo toh pedd underdeveloped nahi.... fukkk jaaga thoddey dina mein... :D :D :D

anilsangwan
March 2nd, 2009, 01:31 PM
Fer toh Saradd-Garamm honni e thee pedd k........ itni si baat ka naa bera in scientistaaa ne?


ताता पाणी ना था बस ताता कर कै सीला करे पाछे गेरया था:o

rajeshchhikara
March 2nd, 2009, 02:09 PM
kuch na hota pani tae pani e ho hai......chemical formula thodi na badle hai microwave per rate of vaporisation pae fark pade hai.....bas jab pedda main gero temp 20-32 c tak ho tae pedda bhi roj hara sa ho jya gya


aap dhore jo va mail aai thi va faltu ki thi sunita ji.........koi khaas fark na padta ............phla chulae pae log roti poya karte jab bhi tae aankh puthya karti.

aap aram tae use karo these waves are not harmful.....

sunitahooda
March 2nd, 2009, 02:44 PM
I have found microwave cooked food delicious, cooks with less oil hence less calories. Even deep frying dishes can be cooked with just few drops of oil and tastes equally good....bas poori and pakoddey bhi bann jatey to kya baat thi:)

satyenderdeswal
March 2nd, 2009, 02:46 PM
err sabte badhiya baat jab hoti jab microwave akey muh main tuk tod tod ke de jata.....se ne :p:p
I have found microwave cooked food delicious, cooks with less oil hence less calories. Even deep frying dishes can be cooked with just few drops of oil and tastes equally good....bas poori and pakoddey bhi bann jatey to kya baat thi:)

sunitahooda
March 2nd, 2009, 02:49 PM
Uss kaam khatar ek koye issa toh lyungi jo muh mai took todd-todd deye jaa:Darr kai nyu kahdey akk bana bi mai dyunga;) Manne tai 2 in 1 chahiye:rock
err sabte badhiya baat jab hoti jab microwave akey muh main tuk tod tod ke de jata.....se ne :p:p

satyenderdeswal
March 2nd, 2009, 03:59 PM
:boxing:boxing:boxingha ha ha. Wish you best of luck...
Uss kaam khatar ek koye issa toh lyungi jo muh mai took todd-todd deye jaa:Darr kai nyu kahdey akk bana bi mai dyunga;) Manne tai 2 in 1 chahiye:rock

sunitahooda
March 2nd, 2009, 04:15 PM
Ek scheme batani paddegi Microwave bechann aalya tayi....Ke Microave ke saath Took toddaniya free:rockHoli ke shubh avsar par:D
:boxing:boxing:boxingha ha ha. Wish you best of luck...

satyenderdeswal
March 2nd, 2009, 04:16 PM
Correction kar di..Kuchh bolta te tu bhi pher merte matlab pucchti "ek ke matlab se is baat ka"
Ek scheme batani paddegi Microwave bechann aalya tayi....Ke Microave ke saath Took toddaniya free:rockHOLI ke shubh avsar par:D

me_rathee
March 3rd, 2009, 11:16 AM
Virender is it true that Microwave cooked food is harmful to consume? I use microwave a lot, please throw some light on this too:)



Sunita Bebe yo te alag alag cheeza pe laagoo hoya kare.

rakeshsehrawat
March 27th, 2009, 12:40 PM
http://www.gallawa.com/microtech/howcook.html

satyenderdeswal
March 27th, 2009, 02:01 PM
Virender ji. Thanx a ton
Its really very helpfull information provided by you...
Previously I was not aware even of ABCD of Microwave...
Sunita Bebe yo te alag alag cheeza pe laagoo hoya kare.

sunitahooda
March 27th, 2009, 02:07 PM
No plastic containers in microwave.

Instead, he recommends using glass, such as Corning Ware, Pyrex or ceramic. Containers for heating food... You get the same results, only without the dioxin.

So such things as TV dinners, instant ramen and soups, etc.,should be removed from the container and heated in something else.

Paper isn't bad but you don't know what is in the paper.

No plastic wrap in microwave.

P.S. the pantry boy in my office used to warm food in any container, be it aluminium/ glass/plastic/ steel....had to buy a set of glassware that was microwave safe.


Virender ji. Thanx a ton
Its really very helpfull information provided by you...
Previously I was not aware even of ABCD of Microwave...

satyenderdeswal
March 27th, 2009, 02:10 PM
Sunita Mam..
Can we use aluminium foil (We chamakni si jismein roti pack karya karey)in Microwave..????(
No plastic containers in microwave.

Instead, he recommends using glass, such as Corning Ware, Pyrex or ceramic. Containers for heating food... You get the same results, only without the dioxin.

So such things as TV dinners, instant ramen and soups, etc.,should be removed from the container and heated in something else.

Paper isn't bad but you don't know what is in the paper.

No plastic wrap in microwave.

VPannu
March 27th, 2009, 02:18 PM
How Do Microwaves Cook Food?
the food is removed from the oven, there is no residual radiation remaining in the food. In this regard, a microwave oven is much like and electric light that stops glowing when it is turned off.Rathee saab, kindly don't copy paste. Rakesh ne 2 be parchee pakad li se:tamatar

sunitahooda
March 27th, 2009, 02:21 PM
Humbey bera sai....Sab "FLYING" aale paak rey sain:rock:D
Rathee saab, kindly don't copy paste. Rakesh ne 2 be parchee pakad li se:tamatar

VPannu
March 27th, 2009, 02:26 PM
Humbey bera sai....Sab "FLYING" aale paak rey sain:rock:D hahahahaaahahahaha....flying.
Sunitaji, simple sa formula se parchee pakdan ka......koye bhi laambi si english ki post poori copy kar ke google me ghaal do, aap bata dega farjee se ak na :D :thappad

sunitahooda
March 27th, 2009, 02:30 PM
Humney bi bera sai....par aaade to selected thread padhan ka moukka mil jaa sai....GOOGLE mai baddan ka tame kis dhorey sai....mera tai ibbe office ka FREE NET bi na sai:o
hahahahaaahahahaha....flying.
Sunitaji, simple sa formula se parchee pakdan ka......koye bhi laambi si english ki post poori copy kar ke google me ghaal do, aap bata dega farjee se ak na :D :thappad

satyenderdeswal
March 27th, 2009, 02:32 PM
hmmm.
Yes. its really a time consuming work to search on google for such usefull info when u r getting it on jatland without wasting time...:)
(Waiting for Nishant Ji's comment)
Humney bi bera sai....par aaade to selected thread padhan ka moukka mil jaa sai....GOOGLE mai baddan ka tame kis dhorey sai....mera tai ibbe office ka FREE NET bi na sai:o

me_rathee
March 27th, 2009, 04:29 PM
No plastic containers in microwave.

Instead, he recommends using glass, such as Corning Ware, Pyrex or ceramic. Containers for heating food... You get the same results, only without the dioxin.


Sunita Ji, Tough plastic aaya kare microwave mein cooking ke liye (TUPPERWARE AALE)..........to aap manne yeh batao kii woh bhi safe konya ke...........aaj e likad ke bagaunga saare ke saare tupperware aale bartan.

sunitahooda
March 27th, 2009, 04:46 PM
Manna bagao....wey to safe bataya karein....arr ghar ghar mai jaa liye...mahangey bi nirrey sain:)
No plastic containers in microwave.

Instead, he recommends using glass, such as Corning Ware, Pyrex or ceramic. Containers for heating food... You get the same results, only without the dioxin.


Sunita Ji, Tough plastic aaya kare microwave mein cooking ke liye (TUPPERWARE AALE)..........to aap manne yeh batao kii woh bhi safe konya ke...........aaj e likad ke bagaunga saare ke saare tupperware aale bartan.