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microwave ovens effect on food.
#1
Bones
Bones
I had a short conversation last night with a friend about microwave ovens effect on food. I generally believe as a scientist other than standing right in front of a running microwave there is little danger in eating food put through a microwave for a few minutes to reheat etc.
can you guys back this up with peer-reviewed proof for or against?
can you guys back this up with peer-reviewed proof for or against?
#2
Terrik
Terrik
My ex-gf refused to eat anything microwaved because she swore up and down it was poisonous to ea microwaved food.
#3
figmentPez
figmentPez
To the best of my knowledge all heating of food destroys nutrients, and many forms of heating also produce toxins. Especially high heat like frying or grilling, and cooking methods that produce incomplete combustion like smoking and, again, grilling. That's not to say that the raw food movement is right, as just as cooking destroys some nutrients, it makes many more readily available.
I have no idea if microwaving is better or worse than boiling, fying, baking, grilling, toasting, steaming, poaching, braising, etc. all I know is that it's different and probably destroys different nutrients than other cooking methods. If those nutrients are important, I don't know. Chances are the effects of microwaves on all food globally is far to complex to study as a whole, and I've never heard of anyone with a specific focus of study on the issue. I'd be fascinated to know if anyone does know of specific research, though. My sister belongs to the "microwaves are bad" group, and while she's generally not fanatical about it, she avoids using the microwave whenever possible.
I have no idea if microwaving is better or worse than boiling, fying, baking, grilling, toasting, steaming, poaching, braising, etc. all I know is that it's different and probably destroys different nutrients than other cooking methods. If those nutrients are important, I don't know. Chances are the effects of microwaves on all food globally is far to complex to study as a whole, and I've never heard of anyone with a specific focus of study on the issue. I'd be fascinated to know if anyone does know of specific research, though. My sister belongs to the "microwaves are bad" group, and while she's generally not fanatical about it, she avoids using the microwave whenever possible.
#4
ThatGrinningIdiot!
Excess heat will destroy nutrients, but proper cooking of food is a kind of pre-decomposition process that allows for easier digestion and absorption. There are minerals and vitamins that are more sensitive to heat than others.
*Opinion is subject to discrediting and amending.*
ThatGrinningIdiot!
Microwaves use a high intensity radio frequency that generates heat within the water molecules present in most foods. I'm certain that people are paranoid of such devices because of ignorance, and the fear that comes with the word "radiation."To the best of my knowledge all heating of food destroys nutrients, and many forms of heating also produce toxins. Especially high heat like frying or grilling, and cooking methods that produce incomplete combustion like smoking and, again, grilling. That's not to say that the raw food movement is right, as just as cooking destroys some nutrients, it makes many more readily available.
I have no idea if microwaving is better or worse than boiling, fying, baking, grilling, toasting, steaming, poaching, braising, etc. all I know is that it's different and probably destroys different nutrients than other cooking methods. If those nutrients are important, I don't know. Chances are the effects of microwaves on all food globally is far to complex to study as a whole, and I've never heard of anyone with a specific focus of study on the issue. I'd be fascinated to know if anyone does know of specific research, though. My sister belongs to the "microwaves are bad" group, and while she's generally not fanatical about it, she avoids using the microwave whenever possible.
Excess heat will destroy nutrients, but proper cooking of food is a kind of pre-decomposition process that allows for easier digestion and absorption. There are minerals and vitamins that are more sensitive to heat than others.
*Opinion is subject to discrediting and amending.*
#5
Chibibar
Excess heat will destroy nutrients, but proper cooking of food is a kind of pre-decomposition process that allows for easier digestion and absorption. There are minerals and vitamins that are more sensitive to heat than others.
*Opinion is subject to discrediting and amending.*[/QUOTE]
I agree. Just make sure you microwave your food in a microwave safe container. If you put in a plastic container that is no microwave safe, it can be dangerous since the plastic will melt into your food... blah!
Chibibar
Microwaves use a high intensity radio frequency that generates heat within the water molecules present in most foods. I'm certain that people are paranoid of such devices because of ignorance, and the fear that comes with the word "radiation."To the best of my knowledge all heating of food destroys nutrients, and many forms of heating also produce toxins. Especially high heat like frying or grilling, and cooking methods that produce incomplete combustion like smoking and, again, grilling. That's not to say that the raw food movement is right, as just as cooking destroys some nutrients, it makes many more readily available.
I have no idea if microwaving is better or worse than boiling, fying, baking, grilling, toasting, steaming, poaching, braising, etc. all I know is that it's different and probably destroys different nutrients than other cooking methods. If those nutrients are important, I don't know. Chances are the effects of microwaves on all food globally is far to complex to study as a whole, and I've never heard of anyone with a specific focus of study on the issue. I'd be fascinated to know if anyone does know of specific research, though. My sister belongs to the "microwaves are bad" group, and while she's generally not fanatical about it, she avoids using the microwave whenever possible.
Excess heat will destroy nutrients, but proper cooking of food is a kind of pre-decomposition process that allows for easier digestion and absorption. There are minerals and vitamins that are more sensitive to heat than others.
*Opinion is subject to discrediting and amending.*[/QUOTE]
I agree. Just make sure you microwave your food in a microwave safe container. If you put in a plastic container that is no microwave safe, it can be dangerous since the plastic will melt into your food... blah!
#6
Math242
Math242
i don't know if it's unhealthy but i sure makes most foods taste like shit
#7
Chazwozel
Excess heat will destroy nutrients, but proper cooking of food is a kind of pre-decomposition process that allows for easier digestion and absorption. There are minerals and vitamins that are more sensitive to heat than others.
*Opinion is subject to discrediting and amending.*[/QUOTE]
Microwaves generate microwaves not radio waves. Although both are a form of electromagnetic radiation. You're right though... all the microwaves do is heat up the water in your food.
Chazwozel
Microwaves use a high intensity radio frequency that generates heat within the water molecules present in most foods. I'm certain that people are paranoid of such devices because of ignorance, and the fear that comes with the word "radiation."To the best of my knowledge all heating of food destroys nutrients, and many forms of heating also produce toxins. Especially high heat like frying or grilling, and cooking methods that produce incomplete combustion like smoking and, again, grilling. That's not to say that the raw food movement is right, as just as cooking destroys some nutrients, it makes many more readily available.
I have no idea if microwaving is better or worse than boiling, fying, baking, grilling, toasting, steaming, poaching, braising, etc. all I know is that it's different and probably destroys different nutrients than other cooking methods. If those nutrients are important, I don't know. Chances are the effects of microwaves on all food globally is far to complex to study as a whole, and I've never heard of anyone with a specific focus of study on the issue. I'd be fascinated to know if anyone does know of specific research, though. My sister belongs to the "microwaves are bad" group, and while she's generally not fanatical about it, she avoids using the microwave whenever possible.
Excess heat will destroy nutrients, but proper cooking of food is a kind of pre-decomposition process that allows for easier digestion and absorption. There are minerals and vitamins that are more sensitive to heat than others.
*Opinion is subject to discrediting and amending.*[/QUOTE]
Microwaves generate microwaves not radio waves. Although both are a form of electromagnetic radiation. You're right though... all the microwaves do is heat up the water in your food.
#8
@Li3n
@Li3n
Don't they all have Faraday cages in them?!other than standing right in front of a running microwave
#9
Cajungal
Cajungal
Food tastes better reheated in an oven or a stovetop. That's all I know for sure.
Once I got an email that said something negative about microwaves, followed by THIS IS HOW SHERYL CROW GOT CANCER!!! I assume it was 100% accurate.
Once I got an email that said something negative about microwaves, followed by THIS IS HOW SHERYL CROW GOT CANCER!!! I assume it was 100% accurate.
#10
Krisken
Krisken
This is political? Be honest, you figured it belonged here because people involved are willfully ignorant. 
#11
SpecialKO
SpecialKO
This is political? Be honest, you figured it belonged here because people involved are willfully ignorant.
#12
MindDetective
MindDetective
If our food is truly radioactive, then I think it would be pretty clear by all the people getting sick. People fear what they don't understand, I guess.Wikipedia said:The symptoms of radiation sickness become more serious (and the chance of survival decreases) as the dosage of radiation increases. A few symptom-free days may pass between the appearance of the initial symptoms and the onset of symptoms of more severe illness associated with higher doses of radiation.[5] Nausea and vomiting generally occur within 24–48 hours after exposure to mild (1–2 Gy) doses of radiation. Headache, fatigue, and weakness are also seen with mild exposure.[5]
#13
Krisken
Krisken
It's true. You people terrify me.
#14
Hylian
Hylian
I have nothing new to add to this topic that has not already been stated but I am going to say something anyways.
Microwaving your food is not going to kill you and as far as most people can tell it does not destroy any more nutrients than other forms of cooking.
Microwaving your food is not going to kill you and as far as most people can tell it does not destroy any more nutrients than other forms of cooking.
#15
Covar
Covar
Tell your friend to stop living in the 50s.
The worst thing microwaves do to your food is dry them out.
The worst thing microwaves do to your food is dry them out.
#16
sixpackshaker
sixpackshaker
Be glad that most of you are young enough to miss the Microwave Revolution. There were cook books out there on how to cook fresh chicken in the Microwave... nothing like trying to serve people 7lbs of rubber.
But putting Orville Redenbacher's pop corn in a brown paper bag, a lump of butter, salt n pepper.... was some pretty good eats.
Until the bag caught on fire that one time.
But putting Orville Redenbacher's pop corn in a brown paper bag, a lump of butter, salt n pepper.... was some pretty good eats.
Until the bag caught on fire that one time.
#17
ThatGrinningIdiot!
Excess heat will destroy nutrients, but proper cooking of food is a kind of pre-decomposition process that allows for easier digestion and absorption. There are minerals and vitamins that are more sensitive to heat than others.
*Opinion is subject to discrediting and amending.*[/QUOTE]
Microwaves generate microwaves not radio waves. Although both are a form of electromagnetic radiation. You're right though... all the microwaves do is heat up the water in your food.[/QUOTE]
I felt as though there was something wrong with my answer. At least you knew what it was.
ThatGrinningIdiot!
Microwaves use a high intensity radio frequency that generates heat within the water molecules present in most foods. I'm certain that people are paranoid of such devices because of ignorance, and the fear that comes with the word "radiation."To the best of my knowledge all heating of food destroys nutrients, and many forms of heating also produce toxins. Especially high heat like frying or grilling, and cooking methods that produce incomplete combustion like smoking and, again, grilling. That's not to say that the raw food movement is right, as just as cooking destroys some nutrients, it makes many more readily available.
I have no idea if microwaving is better or worse than boiling, fying, baking, grilling, toasting, steaming, poaching, braising, etc. all I know is that it's different and probably destroys different nutrients than other cooking methods. If those nutrients are important, I don't know. Chances are the effects of microwaves on all food globally is far to complex to study as a whole, and I've never heard of anyone with a specific focus of study on the issue. I'd be fascinated to know if anyone does know of specific research, though. My sister belongs to the "microwaves are bad" group, and while she's generally not fanatical about it, she avoids using the microwave whenever possible.
Excess heat will destroy nutrients, but proper cooking of food is a kind of pre-decomposition process that allows for easier digestion and absorption. There are minerals and vitamins that are more sensitive to heat than others.
*Opinion is subject to discrediting and amending.*[/QUOTE]
Microwaves generate microwaves not radio waves. Although both are a form of electromagnetic radiation. You're right though... all the microwaves do is heat up the water in your food.[/QUOTE]
I felt as though there was something wrong with my answer. At least you knew what it was.
#18
Eriol
Microwave ovens use radio waves to cook things. Hell, many early on were called "radio ranges" for a reason.
Eriol
The WORD "microwave" is from the fact that it's in a specific part of what we label as "radio waves" and so yes, they are radio waves. And people even communicate in the "microwave band" too. See Microwave, Radio spectrum (things considered "radio" both above AND below "microwaves" there), and Microwave oven (where it says most are at 2.45GHz, which is 122mm wavelength). The wavelength there again puts it in the UHF range, and even inside of Bluetooth, which according to wiki is in 2402-2480 MHz or 2.402-2.480GHz.Microwaves generate microwaves not radio waves. Although both are a form of electromagnetic radiation. You're right though... all the microwaves do is heat up the water in your food.
Microwave ovens use radio waves to cook things. Hell, many early on were called "radio ranges" for a reason.
#19
figmentPez
figmentPez
I thought they heated fat, sugar, alcohol and some other molecules as well.Microwaves generate microwaves not radio waves. Although both are a form of electromagnetic radiation. You're right though... all the microwaves do is heat up the water in your food.
#20
Necronic
Necronic
They do (well sorta), its a common misconception that microwaves only heat water molecules. Here's how a microwave works. Many (most) molecules have what is known as a dipole moment, molecules with such a moment are caled 'polar'. What this means is that there is a non-uniform charge on the molecule. Take for instance the molecule A-B. A pulls electrons to it stronger than B does, which makes A more negative and B more positive, which makes it polar.
Polar molecules will align themselves in an electromagnetic field. A microwave oven generates that field. By alternating the field the angle of alignment is changed, which speeds up the rotation. To make a comparison, think of a merry go round on the playground. Your friend gets on it (drunk of course) and you grab a handle and spin it. Each time it goes around you grab a handle and spin it again. After a couple goes your friend is spinning really fast and performing a move that I like to call 'the vomit sprinkler'.
Heat is, by definition, kinetic energy. Rotational motion of a molecule is a form of kinetic energy. Therefore, by speeding up the rotation of the molecule you increase the heat of the molecule, and therefore the overall heat of the system.
So, for a microwave to heat something, you just need a polar molecule. Many many many many molecules found in organic systems are polar, so you end up having all sorts of stuff getting hot, which hopefully will make the whole system uniformly hot.
Here's where its different from conventional heating. In a microwave all of the energy is coming into the system at the polar molecules. This means that it isn't uniform, which means that an area with a higher concentration of polar molecules will reach a higher temperature than the system as a whole finishes at after the heat transfers. The transfer of energy happens fast, but in some systems it could leave you with superheated regions.
An example of this is the experiment where you put a tall container of water in the microwave and turn it on for a while. When you pull it out its not boiling, but if you dip a spoon into it the water flash boils and explodes all over the place (by the way don't try this at home, its seriously dangerous). This is because the water in the bottom of the container is well above the boiling point, but isn't boiling due to the pressure of the cooler water above it. In lab work this is what's known as 'bumping' and it is really bad (I once had a vial of benzoic acid bump all over my face.) To avoid that people use 'boiling chips' which are high surface area, inert pebbles that induce boiling (which causes enough convection to maintain an even temperature.)
Anyways, totally digressing. The point is that in food that is being microwaved you could have very small superheated regions that are undergoing reactions that would not be possible at normal (or cooking) temperatures. You may think its crazy to think that you are getting to that high of a temperature in a reall tiny area, but its not something unique to microwaves. There is a tool called a(n) (ultra)sonicator that basically just shakes really fast, and it can get local (and really small) temperatures up to 5000 K, slightly less than the temperature of the sun, 5800K (this is actually caused by creating miniature vacuums/cavitation, not from direct heat generation from the shaking.)
Anyways, it is possible that in those microscopic (really nanoscopic) high temperature regions you are undergoing all sorts of crazy reactions that are energetically impossible at lower temperatures, and with the vast array of reactants you have in an complex biological medium (aka 'food') you could end up with some very toxic substances in it.
HOWEVER. The mitigating factor here is scale. You may be generating a toxic molecule, but you may literally only be generating a single or a handful (which could be thousands and its still no biggie) of molecules, so it probably doesn't matter. But the mechanisms are there.
Polar molecules will align themselves in an electromagnetic field. A microwave oven generates that field. By alternating the field the angle of alignment is changed, which speeds up the rotation. To make a comparison, think of a merry go round on the playground. Your friend gets on it (drunk of course) and you grab a handle and spin it. Each time it goes around you grab a handle and spin it again. After a couple goes your friend is spinning really fast and performing a move that I like to call 'the vomit sprinkler'.
Heat is, by definition, kinetic energy. Rotational motion of a molecule is a form of kinetic energy. Therefore, by speeding up the rotation of the molecule you increase the heat of the molecule, and therefore the overall heat of the system.
So, for a microwave to heat something, you just need a polar molecule. Many many many many molecules found in organic systems are polar, so you end up having all sorts of stuff getting hot, which hopefully will make the whole system uniformly hot.
Here's where its different from conventional heating. In a microwave all of the energy is coming into the system at the polar molecules. This means that it isn't uniform, which means that an area with a higher concentration of polar molecules will reach a higher temperature than the system as a whole finishes at after the heat transfers. The transfer of energy happens fast, but in some systems it could leave you with superheated regions.
An example of this is the experiment where you put a tall container of water in the microwave and turn it on for a while. When you pull it out its not boiling, but if you dip a spoon into it the water flash boils and explodes all over the place (by the way don't try this at home, its seriously dangerous). This is because the water in the bottom of the container is well above the boiling point, but isn't boiling due to the pressure of the cooler water above it. In lab work this is what's known as 'bumping' and it is really bad (I once had a vial of benzoic acid bump all over my face.) To avoid that people use 'boiling chips' which are high surface area, inert pebbles that induce boiling (which causes enough convection to maintain an even temperature.)
Anyways, totally digressing. The point is that in food that is being microwaved you could have very small superheated regions that are undergoing reactions that would not be possible at normal (or cooking) temperatures. You may think its crazy to think that you are getting to that high of a temperature in a reall tiny area, but its not something unique to microwaves. There is a tool called a(n) (ultra)sonicator that basically just shakes really fast, and it can get local (and really small) temperatures up to 5000 K, slightly less than the temperature of the sun, 5800K (this is actually caused by creating miniature vacuums/cavitation, not from direct heat generation from the shaking.)
Anyways, it is possible that in those microscopic (really nanoscopic) high temperature regions you are undergoing all sorts of crazy reactions that are energetically impossible at lower temperatures, and with the vast array of reactants you have in an complex biological medium (aka 'food') you could end up with some very toxic substances in it.
HOWEVER. The mitigating factor here is scale. You may be generating a toxic molecule, but you may literally only be generating a single or a handful (which could be thousands and its still no biggie) of molecules, so it probably doesn't matter. But the mechanisms are there.
#21
drifter
drifter
Possibly a stupid question, but: I thought it was the lack of a nucleation point that led to water in a microwave not boiling, hence the boiling chips?An example of this is the experiment where you put a tall container of water in the microwave and turn it on for a while. When you pull it out its not boiling, but if you dip a spoon into it the water flash boils and explodes all over the place (by the way don't try this at home, its seriously dangerous). This is because the water in the bottom of the container is well above the boiling point, but isn't boiling due to the pressure of the cooler water above it. In lab work this is what's known as 'bumping' and it is really bad (I once had a vial of benzoic acid bump all over my face.) To avoid that people use 'boiling chips' which are high surface area, inert pebbles that induce boiling (which causes enough convection to maintain an even temperature.)
#22
Chibibar
Chibibar
Necronic: wow. that is really cool.
What is the main difference between commercial microwave and residential? I notice that I can heat a can (the can that came in) in a commercial microwave, but if I put in a residential version..... well, you get sparks and not pretty microwave.
What is the main difference between commercial microwave and residential? I notice that I can heat a can (the can that came in) in a commercial microwave, but if I put in a residential version..... well, you get sparks and not pretty microwave.
#23
MindDetective
I had heard this is a problem mostly with deionized water and that it doesn't work on tap water but I just read on wikipedia that this is false. Looks like the reason it doesn't happen in coffee cups, etc, is due to imperfections in the cup, which serve as nucleation points. I certainly will be extra careful microwaving water from now on...
MindDetective
Possibly a stupid question, but: I thought it was the lack of a nucleation point that led to water in a microwave not boiling, hence the boiling chips?[/QUOTE]An example of this is the experiment where you put a tall container of water in the microwave and turn it on for a while. When you pull it out its not boiling, but if you dip a spoon into it the water flash boils and explodes all over the place (by the way don't try this at home, its seriously dangerous). This is because the water in the bottom of the container is well above the boiling point, but isn't boiling due to the pressure of the cooler water above it. In lab work this is what's known as 'bumping' and it is really bad (I once had a vial of benzoic acid bump all over my face.) To avoid that people use 'boiling chips' which are high surface area, inert pebbles that induce boiling (which causes enough convection to maintain an even temperature.)
I had heard this is a problem mostly with deionized water and that it doesn't work on tap water but I just read on wikipedia that this is false. Looks like the reason it doesn't happen in coffee cups, etc, is due to imperfections in the cup, which serve as nucleation points. I certainly will be extra careful microwaving water from now on...
#24
Baerdog
Baerdog
Commercial microwave ovens like you might find in a restaurant tend to be more powerful than residential models.Necronic: wow. that is really cool.
What is the main difference between commercial microwave and residential? I notice that I can heat a can (the can that came in) in a commercial microwave, but if I put in a residential version..... well, you get sparks and not pretty microwave.
#25
strawman
strawman
To go a bit further, the polarized molecules will only spin faster if they are resonant with the RF field. Microwaves exploit this to target water - the frequency used puts a lot of energy into the water molecules because they spin at the same frequency of the field (it's like having a gazillion tiny electric motors in your food).
Other molecules will rotate, and absorb energy, but not at the rate that the water molecules will.
Also, the RF will only penetrate so much material before the energy is too low to take effect.
Lastly, there is a rotating reflector in front of the microwave cavity (the part that actually generates the RF) that causes the RF to be distributed around the inside of the microwave. Combined with a rotating platter, localized superheating is unlikely.
One can still superheat foods, such as water, but unless you observe plasmas inside your microwave you are not likely reaching temperatures that will change the molecular structure of the food enough to be a biological threat.
Other molecules will rotate, and absorb energy, but not at the rate that the water molecules will.
Also, the RF will only penetrate so much material before the energy is too low to take effect.
Lastly, there is a rotating reflector in front of the microwave cavity (the part that actually generates the RF) that causes the RF to be distributed around the inside of the microwave. Combined with a rotating platter, localized superheating is unlikely.
One can still superheat foods, such as water, but unless you observe plasmas inside your microwave you are not likely reaching temperatures that will change the molecular structure of the food enough to be a biological threat.
#26
Hailey Knight
Hailey Knight
Necronic has terrified me from microwaves forever.
#27
PatrThom
PatrThom
To add what I know to the mix...
-Microwave ovens do not heat uniformly, just like waving a flashlight around will light a room unevenly. There is usually a rotating 'fan' which scatters the radiation around inside the chamber to compensate by spreading it around some more. Having a carousel spreads it around even more.
-Yes, Microwave ovens tend to have a Faraday cage built into the viewing door. This is to keep the microwaves from escaping and wreaking havoc with things nearby (such as internal organs, but probably mostly for electronics, such as...pacemakers, cochlear implants, insulin pumps, etc).
-Lack of nucleation points is indeed what keeps it from boiling, but it is the lack of boiling that really slows down the convection. Liquids diffuse really slowly if they don't have those rising bubbles to help mix things up.
-We already eat quite a bit of irradiated food. Food that is prepared by exposure to actual hard radiation as a means of keeping it fresh longer. Even if microwave ovens were capable of generating hard radiation, we've already done it to ourselves by other means.
-Microwave cooking has actually been shown to be the method which destroys the least amount of vitamins (in vegetables, at least). Yes, even less damage than steaming (from the tests done by one of Kati's cooking magazines, I believe).
-WiFi/BlueTooth do work in and around the same band as Microwave ovens, as referenced in this comic.
-Commercial microwave ovens (and some residential ones, basically the more expensive ones) are safer than cheaper ones because they can vary the power put into the radiation itself. Cheaper ovens vary power by cycling between 100%-0%-100% power with longer 'bursts' for higher power settings. The more expensive ovens actually vary the power put out by the magnetron, which makes them safer for metallic things.
--Patrick
-Microwave ovens do not heat uniformly, just like waving a flashlight around will light a room unevenly. There is usually a rotating 'fan' which scatters the radiation around inside the chamber to compensate by spreading it around some more. Having a carousel spreads it around even more.
-Yes, Microwave ovens tend to have a Faraday cage built into the viewing door. This is to keep the microwaves from escaping and wreaking havoc with things nearby (such as internal organs, but probably mostly for electronics, such as...pacemakers, cochlear implants, insulin pumps, etc).
-Lack of nucleation points is indeed what keeps it from boiling, but it is the lack of boiling that really slows down the convection. Liquids diffuse really slowly if they don't have those rising bubbles to help mix things up.
-We already eat quite a bit of irradiated food. Food that is prepared by exposure to actual hard radiation as a means of keeping it fresh longer. Even if microwave ovens were capable of generating hard radiation, we've already done it to ourselves by other means.
-Microwave cooking has actually been shown to be the method which destroys the least amount of vitamins (in vegetables, at least). Yes, even less damage than steaming (from the tests done by one of Kati's cooking magazines, I believe).
-WiFi/BlueTooth do work in and around the same band as Microwave ovens, as referenced in this comic.
-Commercial microwave ovens (and some residential ones, basically the more expensive ones) are safer than cheaper ones because they can vary the power put into the radiation itself. Cheaper ovens vary power by cycling between 100%-0%-100% power with longer 'bursts' for higher power settings. The more expensive ovens actually vary the power put out by the magnetron, which makes them safer for metallic things.
--Patrick
#28
Necronic
My definition of localized superheating is a lot more tiny than I may have been describing. As an idealized system let's say you have lipids surrounding some small pockets of water. The vast majority of the energy absorbed by the system as a whole will come through these water molecules. They will achieve a pretty high level of energy during that transfer, which should be higher than can be achieved during regular radiant/conductive heating. It could be that the small localized areas where the water connects with the lipids has a higher chance to start some reaction than it would at normal cooking conditions.
Just to be clear though, I'm not saying microwaving food is dangerous. I truly don't think it is. All I am saying is that it is a different set of reaction conditions than you have in a regular cooking system, which means that yes, maybe you are seeing a different final outcome. But really it's only different in an academic sense, which is all I am arguing.
---------- Post added at 05:04 AM ---------- Previous post was at 05:03 AM ----------
My definition of localized superheating is a lot more tiny than I may have been describing. As an idealized system let's say you have lipids surrounding some small pockets of water. The vast majority of the energy absorbed by the system as a whole will come through these water molecules. They will achieve a pretty high level of energy during that transfer, which should be higher than can be achieved during regular radiant/conductive heating. It could be that the small localized areas where the water connects with the lipids has a higher chance to start some reaction than it would at normal cooking conditions.
Just to be clear though, I'm not saying microwaving food is dangerous. I truly don't think it is. All I am saying is that it is a different set of reaction conditions than you have in a regular cooking system, which means that yes, maybe you are seeing a different final outcome. But really it's only different in an academic sense, which is all I am arguing.
Necronic
Thanks for that, I knew I was missing some stuff, particularly the stuff about it being tuned to water. The coffee cup example was bad as well on my part, because as someone mentioned you can do that in any container that doesn't contain enough convection and/or nucleation sitesTo go a bit further, the polarized molecules will only spin faster if they are resonant with the RF field. Microwaves exploit this to target water - the frequency used puts a lot of energy into the water molecules because they spin at the same frequency of the field (it's like having a gazillion tiny electric motors in your food).
Other molecules will rotate, and absorb energy, but not at the rate that the water molecules will.
Also, the RF will only penetrate so much material before the energy is too low to take effect.
Lastly, there is a rotating reflector in front of the microwave cavity (the part that actually generates the RF) that causes the RF to be distributed around the inside of the microwave. Combined with a rotating platter, localized superheating is unlikely.
One can still superheat foods, such as water, but unless you observe plasmas inside your microwave you are not likely reaching temperatures that will change the molecular structure of the food enough to be a biological threat.
My definition of localized superheating is a lot more tiny than I may have been describing. As an idealized system let's say you have lipids surrounding some small pockets of water. The vast majority of the energy absorbed by the system as a whole will come through these water molecules. They will achieve a pretty high level of energy during that transfer, which should be higher than can be achieved during regular radiant/conductive heating. It could be that the small localized areas where the water connects with the lipids has a higher chance to start some reaction than it would at normal cooking conditions.
Just to be clear though, I'm not saying microwaving food is dangerous. I truly don't think it is. All I am saying is that it is a different set of reaction conditions than you have in a regular cooking system, which means that yes, maybe you are seeing a different final outcome. But really it's only different in an academic sense, which is all I am arguing.
---------- Post added at 05:04 AM ---------- Previous post was at 05:03 AM ----------
Thanks for that, I knew I was missing some stuff, particularly the stuff about it being tuned to water. The coffee cup example was bad as well on my part, because as someone mentioned you can do that in any container that doesn't contain enough convection and/or nucleation sitesTo go a bit further, the polarized molecules will only spin faster if they are resonant with the RF field. Microwaves exploit this to target water - the frequency used puts a lot of energy into the water molecules because they spin at the same frequency of the field (it's like having a gazillion tiny electric motors in your food).
Other molecules will rotate, and absorb energy, but not at the rate that the water molecules will.
Also, the RF will only penetrate so much material before the energy is too low to take effect.
Lastly, there is a rotating reflector in front of the microwave cavity (the part that actually generates the RF) that causes the RF to be distributed around the inside of the microwave. Combined with a rotating platter, localized superheating is unlikely.
One can still superheat foods, such as water, but unless you observe plasmas inside your microwave you are not likely reaching temperatures that will change the molecular structure of the food enough to be a biological threat.
My definition of localized superheating is a lot more tiny than I may have been describing. As an idealized system let's say you have lipids surrounding some small pockets of water. The vast majority of the energy absorbed by the system as a whole will come through these water molecules. They will achieve a pretty high level of energy during that transfer, which should be higher than can be achieved during regular radiant/conductive heating. It could be that the small localized areas where the water connects with the lipids has a higher chance to start some reaction than it would at normal cooking conditions.
Just to be clear though, I'm not saying microwaving food is dangerous. I truly don't think it is. All I am saying is that it is a different set of reaction conditions than you have in a regular cooking system, which means that yes, maybe you are seeing a different final outcome. But really it's only different in an academic sense, which is all I am arguing.
#29
Cajungal
Cajungal
AAUUGH I have seen one of those cookbooks! Nasty. Back in culinary school if we had to very quickly test a seasoning we'd made for meat we would cut off a tiny chunk and microwave it in water instead of waiting for a burner to heat up and dirtying a big pan. The meat was sooooo disgusting after being cooked in a microwave.Be glad that most of you are young enough to miss the Microwave Revolution. There were cook books out there on how to cook fresh chicken in the Microwave... nothing like trying to serve people 7lbs of rubber.
But putting Orville Redenbacher's pop corn in a brown paper bag, a lump of butter, salt n pepper.... was some pretty good eats.
Until the bag caught on fire that one time.
#30
sixpackshaker
sixpackshaker
I don't know exactly what happened. My sister in law boiled a couple of eggs in the microwave. When she removed the bowl (large Pyrex measuring cup I think) the eggs exploded. Exploded with such force that the yolks splatted on and stained their 14 foot + ceiling. It must have been like a rocket nozzle for boiling water and yolk. I have no idea how she did not get seriously injured.
#31
GasBandit
GasBandit
My grandfather still has a Radar Range in storage. We don't know if it still works, he ran out of Plutonium for it decades ago.
#32
sixpackshaker
sixpackshaker
We had a second hand 7/11 microwave... It was made by the Radar Range folks (Amana?) It was a beast. Easily the fastest machine to ever boil water. It was easy and cheap to repair... $.50 fuse once a year. But it finally started chewing through fuses pretty fast, and my parents gave up on it after 10 years. They've never had a good microwave since.My grandfather still has a Radar Range in storage. We don't know if it still works, he ran out of Plutonium for it decades ago.
#33
strawman
The internal pressure may be low enough when the egg is in the water to avoid exploding due to the water pressure on the shell, but once removed from the water a superheated egg will explode. While it's certainly dangerous, at least it didn't explode in the water, splashing both boiling egg and boiling water all over the person holding the dish...
strawman
You should never put eggs in the microwave, even in a dish of water. They will explode if you microwave them long enough. It's similar to putting a can of corn on the stove without opening the can - eventually the internal pressure becomes too large for the can to handle. The same thing would happen if you put the egg directly on the stove burner - too much heat too quickly. The microwave puts the heat into the egg directly, quickly, and unevenly. Water on the stove the water puts heat into the egg slowly and evenly.I don't know exactly what happened. My sister in law boiled a couple of eggs in the microwave. When she removed the bowl (large Pyrex measuring cup I think) the eggs exploded. Exploded with such force that the yolks splatted on and stained their 14 foot + ceiling. It must have been like a rocket nozzle for boiling water and yolk. I have no idea how she did not get seriously injured.
The internal pressure may be low enough when the egg is in the water to avoid exploding due to the water pressure on the shell, but once removed from the water a superheated egg will explode. While it's certainly dangerous, at least it didn't explode in the water, splashing both boiling egg and boiling water all over the person holding the dish...