Microwave ovens

[tipsy]

i loved watching those ads while i was all f#ckerd up...

[Mahk]

Lmao, jj!

This is your brain on drugs:

[harpy]

I don't normally take drugs, but after watching that video I have a sudden urge to.

[BlackCats]

[Fungus]

Just came across this thread .. seems to be a lot of misinformation about microwave ovens ..
They simply use a radio transmitter at very high frequencies which is tuned to the water molecules resonant frequency. It is not ionising radiation and there isnt any after .. And the metal cage of the microwave stops any radiation from coming out, in the door of the microwave there is small perforations which are smaller than the wavelength of the microwaves so you can look through but still not get any radiation. But even if you did, it only produces a heating effect ..
I can only really think of a few hazards of using microwaves:
If you heat up liquid in a microwave in a smooth container, there is a small chance of it exploding when you take it out/add powder to it; for water to boil it has to have 'seed bubbles' which form around tiny pockets of air and in a microwave with smooth containers the water can get superheated and above the boiling temperature of water, leading to a steam explosion when taken out. However this is easy to get around by adding whatever powder (sugar etc) first before it's put into the microwave.
Then if you have metal objects in a microwave oven they can heat up a lot and be dangerous; they act as antennae for the microwave frequency and an electrical current builds up inside them, because of the resistance of the metal this produces a lot of heat as the eddy currents flow round them.
The reason why a lot of food seems not 'properly cooked' is really because of the inherent properties of the microwave that means it cooks food thoroughly all the way through, meaning it doesnt get 'crispy' on the outside, a lot of new microwave ovens also have a normal element for this purpose ..
And since microwaved food isnt cooked inside anything else which can leach away the nutrients the most that can happen is denaturing of some proteins and enzymes at very high temperatures which happens with any food that is heated up.

[Mahk]

Bravo Fungus! I'm glad to see another forum member apply science instead of superstition to the topic at hand.

From my understanding microwave ovens cook based on friction which generates heat. Much like when one rubs their hands together to warm them on a cold day. Each water, oil, and other polarized molecules in the food vibrates against each other due to the oscillating microwave field and the friction then generates heat.

Water has a hard time reaching temperatures much above boiling (100C/212F), it simply vaporizes in to steam, but oils and tomato based foods have the potential to reach much higher temperatures so they should not be cooked in plastic containers which may melt or leech bad chemicals into the food. Use glass instead.

Very early designs made in the 1950's didn't always have an interlock which prevents operation while the door is open. Those potentially could cause some health issues if the owner opened the door while the unit was on, but otherwise modern day microwave ovens are quite safe.

[Mr Flibble]

Bravo Fungus! I'm glad to see another forum member apply science instead of superstition to the topic at hand.

From my understanding microwave ovens cook based on friction which generates heat.

Exactly, it's science innit? The plate in the microwave goes round, generating friction, which causes heat. The whole micro waves thing is just to throw the hippies off

[Fungus]

The plate only turns to prevent 'hot spots' created by standing waves making bits of the food hotter than other though

[citameht]

I use the microwave oven almost exclusively for cereals.

[Zero]

Microwave ovens are no more destructive than any other form of heating, the high frequency waves cause water molecules to rub against each other creating molecular friction and thus heat.

The energy is changed to heat as soon as food absorbs it, therefore it cannot become radioactive or contaminated.

Microwaves are reflected by the surfaces inside the oven so as long as your microwave oven is in a good state of repair and you are using it correctly the radiation does not escape beyond safe "leakage" levels.

Microwaves have a frequency of 2,450 MHz. The microwaves then pass into the enclosed metal oven cavity where they are reflected around the oven walls and absorbed in food or drink placed in the oven.

If you are truly worried about the effect magnetic fields will have on your health then you should also stop using cellular/mobile telephones, cordless phones and wireless networking technology as they all emit similar magnetic fields and do so for longer sustained periods of time.

If you are convinced that microwave heating contaminates your food somehow then you should perhaps switch a raw diet because it essentially heats organic matter in the same way as any other conventional form of heating does.

Useful reading:
http://www.ccohs.ca/oshanswers/phys_agents/microwave_ovens.html
http://www.doh.wa.gov/ehp/rp/xray/rp-oven.htm
http://www.howstuffworks.com/microwave.htm

I don't own a microwave presently. Not because I am afraid of them, but because I find they make me lazy and I end up cooking things late at night when I otherwise wouldn't bother by any other method, I am sure I will end up getting one again at some point though.

I think they do have the potential to destroy more nutrients than other forms of heating simply because they heat things faster and have greater potential of "over heating" foods.

In my opinion consuming fizzy drinks and processed sugar is more damaging to human health than microwave oven emissions

[Zero]

Water has a hard time reaching temperatures much above boiling (100C/212F), it simply vaporizes in to steam, but oils and tomato based foods have the potential to reach much higher temperatures so they should not be cooked in plastic containers which may melt or leech bad chemicals into the food. Use glass instead.

This is a valid point, you should always ensure you use "microwave safe" containers when heating food, nothing that will begin to melt or break down as a result of the food or drink heating up.

[harpy]

ISTR that the best-substantiated objection to microwave cooking (at least for vegetables) is that you usually have to cover them in water, so nutrients leach out into the water during cooking (as with boiling). So steaming or stir-frying would probably be a better way to go for most things.

I expect I already said this earlier in the thread

[Risker]

I don't think that's right harpy, in fact I think it's the complete opposite. You can cook most vegetables in the microwave with little or no water, meaning they retain more nutrients than other methods of cooking.

[Zero]

I certainly never added any water to frozen veg when I microwaved them. I don't see the point, it just takes longer.

[cedarblue]

interesting thread, and like korn i am 0% knowledgeable on microwaves.

i still dont have one and dont want to use one, it just doesn't feel right for me. i would rather steam veg and bake potatoes etc. why the rush in preparing/cooking food? cooking is half the enjoyment for me when i cook stuff. i have no proof that ovens are any safer than micros but thats just what i do.

[Mahk]

Some vegetables I cook directly in the microwave but some are prone to drying out. The excitation of the water molecules turns them to steam and they leave the vegetable and enter the air. I have frozen pot stickers (Chinese dumplings) for example that will become dry and crusty if I cook them too long. I find for them, as well as other things that dry out, the best approach is to wet their outer surface, put them in a very small puddle of water (1-2 TBLS) cover the bowl with saran wrap ("cling wrap" I think those of you on the other side of the pond call it, no?). If you do so tightly the steam will cause the plastic to dome at first and then suck down and cover the food tightly once the cooking stops. If this is undesirable a small slit about 1 centimeter long in the top will act as a pressure escape valve yet still allow a good degree of "steam cooking" action to occur.


When nutrients are "lost" from cooking it is really that they have been relocated to the steam or boiling water. Ever notice the water is no longer clear at the end of the cooking process? It has become nutrified (if there is such a word). If one consumes that water, say for example when cooking vegetables for a soup, one has gained back the escaped vitamins/minerals. They are arguably even better as they will be more bio-available since your stomach acid is no longer needed to leech them away from the solid food.

[Ruby Rose]

why the rush in preparing/cooking food? cooking is half the enjoyment for me when i cook stuff.

I like cooking too, but seldom have the time to cook a full meal from scratch after I get home from work in the evenings. It's not so much that I want food in a hurry - it's more that I want food before midnight! We tend to use the microwave to reheat pasta etc, and to cook frozen veg.

[Gorilla]

i still dont have one and dont want to use one, it just doesn't feel right for me. i would rather steam veg and bake potatoes etc.

the only things i really use microwaves for is to cook jacket potatoes, because i prefer the way they turn out, i don't like the skins going all hard and dry in the oven - and to reheat leftovers.

cover the bowl with saran wrap ("cling wrap" I think those of you on the other side of the pond call it, no?).

cling film we call it. i had no idea you guys call it saran wrap. what does that mean?

[Zero]

When nutrients are "lost" from cooking it is really that they have been relocated to the steam or boiling water. Ever notice the water is no longer clear at the end of the cooking process? It has become nutrified (if there is such a word). If one consumes that water, say for example when cooking vegetables for a soup, one has gained back the escaped vitamins/minerals. they are arguably even better as they will be more bio-available since your stomach acid is no longer needed to leech them away from the solid food.

It is the heat that destroys the nutrients and enzymes, I can imagine that the water is more "nutritional" than it was prior to the cooking process but certainly not containing anywhere near as many nutrients as the food.

[harpy]

This I think is the source of the point about water in the microwave:

http://news.bbc.co.uk/1/hi/health/3188558.stm

(ETA as you see it's not that recent.)

I'll need to take people's word for it as to whether you do or don't need water for microwaving as I never cook anything in the microwave. I have been known to use it for last-minute defrosting though.

[Mahk]

Gorilla, Saran brand was probably the first to market so their name became synonymous with the product (here at least), similar to Vaseline brand petroleum jelly [not vegan, filtered through bone char BTW] or Kleenex brand tissues [sorry, I don't know what you call that in "English", perhaps the same] or old people may refer to microwave ovens as "RadarRanges".

[Mahk]

This I think is the source of the point about water in the microwave:

http://news.bbc.co.uk/1/hi/health/3188558.stm

It is important to note that the 5 oz. of broccoli that lost much of its vitamins was sitting in 2/3 cup of boiling water! The microwave oven had nothing to do with any nutritional loss in that study, it was the boiling water the broccoli was immersed in. Boiling is boiling.

[Mahk]

It is the heat that destroys the nutrients and enzymes, I can imagine that the water is more "nutritional" than it was prior to the cooking process but certainly not containing anywhere near as many nutrients as the food.

Zero, I don't know if it is the "law" that a vegan has to believe in the benefits of the raw food movement (it seems so reading various threads here in our forum) but I for one don't. I've looked for and have never found a scientific experiment, published in a peer reviewed scholarly journal, which supports it, just anecdotal "I feel so much better" tales. Everything I mentioned regarding the fact that vitamins don't disintegrate into thin air and get destroyed but rather are relocated to the water is documented here as well as the truth about the "enzymes". Further discussion would probably be best for another thread that I'm reluctant to start since enough people already hate me because I dare to discuss topics such as if animal testing exists for any reason. [ I don't condone it in any way, of course.]

[harpy]

It is important to note that the 5 oz. of broccoli that lost much of its vitamins was sitting in 2/3 cup of boiling water! The microwave oven had nothing to do with any nutritional loss in that study, it was the boiling water the broccoli was immersed in. Boiling is boiling.

Yes, that point is made in the BBC report as well.

[Mahk]

If one reads the whole report, true, but a cursory look at just the title implies otherwise:
"Microwaved veg 'loses nutrients'

Vegetables cooked in the microwave may lose ingredients that could help fight cancer."

Using a microwave to boil vegetables seems odd to me. The "steaming" method I described or alternatively no water at all process should be much quicker for one thing. Isn't the whole point of a microwave oven speed? If one submerges broccoli in water the broccoli itself is hardly cooking until the water actually comes to a boil. The water effectively is shielding the broccoli from the direct microwaves themselves and a 2/3 cup of water probably takes about a minute before it will boil (depends on wattage, container etc)

[Zero]

Zero, I don't know if it is the "law" that a vegan has to believe in the benefits of the raw food movement (it seems so reading various threads here in our forum) but I for one don't. I've looked for and have never found a scientific experiment, published in a peer reviewed scholarly journal, which supports it, just anecdotal "I feel so much better" tales. Everything I mentioned regarding the fact that vitamins don't disintegrate into thin air and get destroyed but rather are relocated to the water is documented here as well as the truth about the "enzymes". Further discussion would probably be best for another thread that I'm reluctant to start since enough people already hate me because I dare to discuss topics such as if animal testing exists for any reason. [ I don't condone it in any way, of course.]

Oh it seems you've taken my comments out of context. I wasn't saying that you need to believe in the benefits of a raw diet, I was simply pointing out that if you believe heating your food in a microwave is damaging; since every other form is damaging in the same way (perhaps to a slightly lesser degree in some cases) then you should be worried about all cooked food.

[Zero]

cling film we call it. i had no idea you guys call it saran wrap. what does that mean?

Saran is brand name that was popular in the USA, it is also referred to as plastic wrap over there.

[Mahk]

Oh it seems you've taken my comments out of context. I wasn't saying that you need to believe in the benefits of a raw diet, I was simply pointing out that if you believe heating your food in a microwave is damaging; since every other form is damaging in the same way (perhaps to a slightly lesser degree in some cases) then you should be worried about all cooked food.

Sorry. OK, I get you now.

[Zero]

Sorry. OK, I get you now.

haha it's all good

[harpy]

Here's another summary, this time from that well known scientific journal Newsweek - but it does refer to some actual studies

http://www.newsweek.com/id/123325

In brief, it goes along with the "OK but don't use much water" position. It also mentions that vitamin C doesn't survive heating that well (which I think is true of some other vitamins) so light cooking (by whatever method) is preferable to the 3-day method that used to be popular here in my youth even if you do drink the water.

[Mahk]

"Recent observations suggest that the impact of temperature and cooking on vitamin C may have been overestimated:

Since it is water soluble, vitamin C will strongly leach into the cooking water while cooking most vegetables — but this doesn't necessarily mean the vitamin is destroyed — it's still there, but it's in the cooking water. (This may also suggest how the apparent misconception about the extent to which boiling temperatures destroy vitamin C might have been the result of flawed research: If the vitamin C content of vegetables (and not of the water) was measured subsequent to cooking them, then that content would have been much lower, though the vitamin has not actually been destroyed.)
Not only the temperature, but also the exposure time is significant. Contrary to what was previously and is still commonly assumed, it can take much longer than two or three minutes to destroy vitamin C at boiling point.
It also appears that cooking does not necessarily leach vitamin C in all vegetables at the same rate; it has been suggested that the vitamin is not destroyed when boiling broccoli. This may however just be a result of vitamin C leaching into the cooking water at a slower rate from this vegetable. Copper pots will destroy the vitamin.

Vitamin C enriched teas and infusions have increasingly appeared on supermarket shelves. Such products would be nonsense if boiling temperatures did indeed destroy vitamin C at the rate it had previously been suggested. It should be noted however that as of 2004 most academics not directly involved in vitamin C research still teach that boiling temperatures will destroy vitamin C very rapidly." [emphasis mine]
Wikipedia

I've been making lots of soups recently based on this "consume the water too" principal. That and my discovery that replacing half the salt content with potassium chloride "No Salt" brand salt substitute is a great way to cut my sodium in half and boost my potassium at the same time.

[snivelingchild]

I really don't care if there are no proven ill effects from microwaves. Food cooked in them tastes like poo, so there must be something going on in there. It makes anything with pasta taste like rubber and vegetables taste like cardboard. (those are things I've had cooked in glass, btw, so I wasn't tasting plastic.

[Mahk]

Food cooked in them tastes like poo, so there must be something going on in there. It makes anything with pasta taste like rubber and vegetables taste like cardboard. (those are things I've had cooked in glass, btw, so I wasn't tasting plastic.

I've never tasted poo, but if it tastes like microwaved popcorn then I guess I'd like it. Microwave ovens have their short comings. I've never seen anyone claim they are good for making toast for example, but for many foods they are just as good as conventional ovens but quicker for those of us who like eating food but not so much the preparing of food. "Rubbery texture" is often indicative of over cooking (by any means) I've found. Since microwaves are so quick, the likelihood of this occurring is greater than conventional cooking I suppose. With traditional cooking the margin of error is in minutes, but with a microwave ovens the margin of error is in seconds. Also they differ in power (wattage) so learning the correct cook time for a particular product by trial and error won't translate to other differing strength machines. If one finds an ear of corn wrapped in "cling film" to preserve moisture cooks in 1 minute 30 seconds in one machine says nothing as to how long it will take in another machine.

[snivelingchild]

I've never had noodles be rubbery when being boiled too long. I've even had undercooked noodles from a microwave that were rubbery. Ever tried an Amy's asian noodle stir-fry from a microwave? EEWWWWW! From an oven or toaster oven? Delish!! Oh, and compare microwave popcorn to kernels popped on a stove top. Clear winner there IMO.

[Mahk]

You're right. Over cooked noodles by traditional means would be mushy, not rubbery. I've had bad noodles from the microwave but I attributed it to the bad preprocessing by Amy (etc) and not so much the microwave itself. Pre cooked noodles I've not had good results with though by any means but I can't say I've tried all of them.

Frozen pad thai from any brand by any cooking means makes me barf. Tofu chunks frozen come out awful. I don't blame the microwave for that though.

[Risker]

Popcorn from the stove does taste better than from the microwave, but then when cooked on a stove you cook it in fat. If you compare microwave popcorn to air popped popcorn they taste identical.

I don't generally cook food in the microwave as I find the results are generally better from other methods of cooking, I do however use it for heating food, like tinned beans etc. It's fine for that. I think each method of cooking has it's own use, I wouldn't heat tinned beans in the oven for example.

[Zero]

I think each method of cooking has it's own use, I wouldn't heat tinned beans in the oven for example.

I agree, the microwave has it's place but there are certain things that it is just simply not suitable for.

[Mahk]

"Microwave popcorn" in the States, which comes in sealed paper bags you lay flat in the oven and cook for around 3 minutes, are (typically) loaded with oil/fat and usually a bad for you one at that [hydrogenated]. Quite yummy and nothing like hot air popcorn which I find to be dry and inedible.

There's something about the fumes which are carcinogenic or bad for your lungs in some way. I forget. Not so much a problem with occasional users but everyday addicts and the people who work at the factories where they are produced are getting in trouble I hear. Anyone know more?

[cedarblue]

i hear what you are saying ruby rose & gorilla.

i wasn't meaning to denigrate anyone - micros just aren't for me

[Gorilla]

I agree, the microwave has it's place but there are certain things that it is just simply not suitable for.

^^ totally, and i agree with you too cedar. there was a time after microwaves started becoming popular when people were encouraged to cook just about everything in them (hence microwave cookbooks coming out with recipes from everything from roast dinners to chocolate cakes). these days i think most people who do use them just use them for reheating or cooking the odd side dish etc.

[harpy]

I suspect a lot of us have been put off microwave cooking by having been fed some potato or similar that's been blasted to b*ggery in a pub microwave

[Gorilla]

Gorilla, Saran brand was probably the first to market so their name became synonymous with the product (here at least), similar to Vaseline brand petroleum jelly [not vegan, filtered through bone char BTW] or Kleenex brand tissues [sorry, I don't know what you call that in "English", perhaps the same] or old people may refer to microwave ovens as "RadarRanges".

off topic, but thanks Mahk (and Zero for also explaining). i didn't know Vaseline wasn't vegan, although i think the company are a bit dodgy anyway... we call 'Kleenexes' tissues in English i like how you guys call sticky plasters 'Band-Aids' too. do you call vacuum cleaners 'Hoovers'? i think that's generally a British brand name term.

i like the RadarRange name - sounds very American 50s nuclear family!

[Mahk]

"Sticky plasters"? I hadn't a clue. Yes "Hoovers" might be still used by perhaps 1% of the population but 75% would understand the meaning I'd say.

The really funny ones are when there are sexual connotations between our two languages: rubbers, fags, and fanny packs have completely different meanings here.

When the Orca movie "Free Willy" came out us US folk had no clue why you UK folk were laughing at the title.

[snivelingchild]

Popcorn from the stove does taste better than from the microwave, but then when cooked on a stove you cook it in fat.

All I do is just put dry kernels in a pan, nothing else. Once in a blue moon I'll melt butter over the popcorn after it's been popped, but it's usually salt and nothing else.

[Risker]

I didn't realise you could do that, I always cook it in oil. I'll have to give it a try and see if I can taste the difference.

[Ruby Rose]

Oooh Sniv - good tip, thank you! Let the popping commence!

[cedarblue]

how high do you have the heat sniv??

[Mahk]

Even if you never eat artificial butter flavored popcorn yourself, you still could be in danger of contracting "popcorn lung" just from the fumes your roommates make when they cook the stuff in your shared kitchen!
[YOUTUBE]H02TzPqjBqo&NR[/YOUTUBE]
Note only "butter flavored" stuff ever contains this Diacetyl chemical so hopefully the word "butter" has kept us all away from this stuff at least since turning vegan. I have no idea if the chemical is technically vegan in make up but I can tell you that it is now being animal tested for safety concerns, like it or not. Don't shoot the messenger.

[snivelingchild]

how high do you have the heat sniv??

Usually just on medium heat, with the lid on of course.
....I don't have any popcorn right now and this thread makes me crave it!

[petunia]

proud to say, i just got rid of the stupid thing! (my microwave)
learning to live without it...