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The Physics of Hot Pockets

samzenpus posted about 3 months ago | from the when-you-absolutely-have-to-eat dept.

Idle 222

StartsWithABang (3485481) writes "You've all had the experience: you're all excited to microwave your favorite snack. So you pull it out of the freezer, you throw it in, and you let it rip. A minute or two later, you pull it out, and there it is: boiling on the outside, frozen in the middle. Finally, a physicist answers the eternal question: why do microwaved foods remain frozen on the inside when they reach scalding temperatures on the outskirts? Starts With A Bang explains the whole phenomenon. Bonus for the crisping sleeve explanation!"

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Microwave trays (5, Informative)

Travis Mansbridge (830557) | about 3 months ago | (#47015275)

Also those with rotating microwave trays (because microwaves tend to heat unevenly) ought to be aware that anything at the center of the tray will not get the benefit of rotation and heat at the same rate the entire time. To roll around in a (relatively) even distribution, none of your food should sit in the center of the tray.

Microwave trays (0)

Anonymous Coward | about 3 months ago | (#47015319)

My tray is rectangular and goes forward and backward as well as side to side. Screw that circular junk.

Re:Microwave trays (1)

Andreas . (2995185) | about 3 months ago | (#47015539)

May I see a picture or video of that?

Maytag Wide Glide Re:Microwave trays (0)

Anonymous Coward | about 3 months ago | (#47017039)

A quick google search came up with a Maytag Microwave with WideGlide(TM)

Re:Microwave trays (5, Interesting)

Anonymous Coward | about 3 months ago | (#47015937)

Of course there are microwaves made with competent stirrers and well-placed feeds. Panasonic makes microwave ovens that feature both (the feed is at the bottom of the cavity), so no rotation is necessary. They also use variable fast pulse width modulation to drive the magnetron, resulting in a smooth output power, thus avoiding another common contribution made by on-off duty cycles to burnt skin / frozen middle problems especially at lower power settings. (Triac controlled magnetrons can only go on and off; most PWM microwave ovens not driven by an inverter supply do a cycle on the order of 30 seconds.) There is work on continuous phase shifting, which will avoid heating the same islands in food even in pessimal cases (like poorly conducting food put in the centre of a rotating tray). Finally, there is still substantial research going into probes inserted into food so as to provide feedback to the driver logic (dynamically or for capture into programs which take food type mass as variables) and whether non-invasive probes can provide useful dynamic feedback every time the oven is in use.

The main problem is that the cheapest microwave ovens are just good enough to follow recipes that call for some number of seconds on the high setting while being unreliable at other settings, and the food industry targets its instructions accordingly. This is a global problem, not unique to the USA. However, as large-cavity combination microwave/grill/convection ovens become more popular in densely populated areas (why waste space having two or three ovens? why not coat your microwave with pyrolytic surfaces that you clean by simply baking or roasting something? why not cook with microwaves and brown with the grill simultaneously?) this is likely to change faster than patents expire, especially as several key manufacturers (Panasonic, GE) will not be cannibalizing conventional oven products. The critical path and most visible extra cost to the first time buyer is mainly in the design of trays and dishes which work well under arbitrary conditions in a combo oven, and avoiding damage when someone uses the wrong tray, dish or tool for a given programme.

Re:Microwave trays (1)

zmaragdus (1686342) | about 3 months ago | (#47016711)

Why not do both at the same time? Power draw. A microwave can take over half the available load on a standard household circuit. Most are wired for 15 amps before the breaker starts tripping. Heating elements are just as power-hungry, which is why you typically see electric stoves on a dedicated 240V, 20A circuit. I would guess most houses do not have the wiring to support this.

Re:Microwave trays (1)

31415926535897 (702314) | about 3 months ago | (#47017091)

You may be the foremost microwave geek (I mean that in a good way)!

Since you seem to have given it substantial thought, what would you say are the best standalone and best over-the-range microwaves on the market?

I'll be interested to see if your theory about the combo devices come to pass--I have a hard time seeing it working out, probably because of the trays and dishes. Popular cooking trays for conventional ovens are metallic (e.g. cookie sheets), which would be a catastrophic to have in your combo oven if you accidentally turned the microwave on. You wouldn't want to melt your kid's plastic plate by throwing it in the microwave but accidentally turning the grill on to 500.

Re:Microwave trays (0)

Anonymous Coward | about 3 months ago | (#47017495)

Pyrex seems to work well for dishes that are both oven and microwave safe. There are ceramics that do well too, but you just have to be careful not to get the wrong type that gets too hot in the microwave. Various stainless steel implements work fine in a microwave too due to them being too resistive and too low of a magnetic permeability to get much heating from the microwave, but you have to be careful about the shape and thickness.

Re:Microwave trays (0)

Anonymous Coward | about 3 months ago | (#47016023)

Also those with rotating microwave trays (because microwaves tend to heat unevenly) ought to be aware that anything at the center of the tray will not get the benefit of rotation and heat at the same rate the entire time. To roll around in a (relatively) even distribution, none of your food should sit in the center of the tray.

That's is very true.. But still ineffective at evenly heating the center, they also made toaster ovens. But in these times who can wait an additional few minutes to bake it perfectly.

This was already long known 40 years ago, so this should be filed under stupid s**t. 40 years later and the microwave is still terrible at cooking, but somewhat decent at boiling.

Re:Microwave trays (1)

NotDrWho (3543773) | about 3 months ago | (#47016553)

Toaster ovens also generate a lot of waste heat. I don't need a little space heater in my kitchen in the summer--taking FOREVER to heat my goddamned Hot Pocket!

Re:Microwave trays (0)

Anonymous Coward | about 3 months ago | (#47017509)

who can wait an additional few minutes to bake it perfectly.

I may not be able to recall the exact cook time, but I sure as hell remember that it isn't "a few minutes" more than what it takes to nuke the damn things.

GIABT FROARIT S THE REAS)Oklsm! (0)

For a Free Internet (1594621) | about 3 months ago | (#47015277)

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Re:GIABT FROARIT S THE REAS)Oklsm! (-1, Offtopic)

Travis Mansbridge (830557) | about 3 months ago | (#47015337)

I hear it's amazing when the famous purple stuffed worm in flap-jaw space with the tuning fork does a raw blink on Hara-Kiri Rock. I need scissors! 61!!

Somebody needs to buy... (4, Interesting)

Bin_jammin (684517) | about 3 months ago | (#47015279)

a microwave with more than 300 watts of power. I've never had the issue of hot outside/cold inside, my problems have always been of the hot outside/nuclear inferno/solar coronal mass ejection on the inside variety, regardless of where I've microwaved them. I don't even follow the instructions on the package very closely, just pull it out of the wrapper, put it in the sleeve, toss it in, slap the door shut, 3 or so minutes, and out comes an external breading hot to the touch with napalm in the center. Maybe there are just a lot of broken microwaves, or even more likely, people that don't know how to use them properly?

Re: Somebody needs to buy... (1)

KramberryKoncerto (2552046) | about 3 months ago | (#47015369)

Not for defrost...

Re:Somebody needs to buy... (1)

Jmc23 (2353706) | about 3 months ago | (#47015375)

Perhaps YOU need to buy a less powerful microwave and/or read the instructions.

Re: Somebody needs to buy... (0)

Anonymous Coward | about 3 months ago | (#47016503)

I deliberately tried to find a low wattage 120v microwave for this exact reason... ...but below a certain wattage you run into marine-use units at 24 / 48 volts around 450 watts or so, IIRC.

I settled on a busted 600w unit given to me that i repaired. (fcc ship radar electronic tech)

BTW, NEVER DIY repair on microwave ovens unless you know exactly what you are doing. i know i don't need to say this on slashdot, but my OCD makes me say it.

An open magnetron being powered up killed a guy in the area years ago while he was testing it without knowing what he was doing.

When my brother inlaw said he was going to repair his last month, me offering to go halves on a new one was all i could do to dissuade him, if i could have afforded it i'd have outright got him one. people / general public do not realize the dangers.

anyhow, back on point, my 600w unit cooks at a very nice thorough pace, even if food is centered.

Re: Somebody needs to buy... (0)

Anonymous Coward | about 3 months ago | (#47016567)

same AC here, before someone asks, i didn't offer to repair my bro in laws because we determined that the digital board had a failure, and the board cost wasnt worth it.
my 600w unit had no digital components, no power settings, just a rotating knob with a mechanical bell when done.

Re:Somebody needs to buy... (1)

aevan (903814) | about 3 months ago | (#47015559)

My place reeked for a week as I went through a few dozen backs of microwave popcorn, trying to find the balance of power and time that didn't leave either a bag of charcoal, or a bag of kernals. We don't even pretend that popcorn button on it is anything more than a cruel joke. [Ended up being 60% for 1m50].

Oven instruction? Sure. Stove-top instructions? Maybe. Microwave instructions? Put in the same category as "may have been in the same building as a peanut" disclaimers: there on the off chance that it might be important to that one in a hundred people it applies to. Every one else use (learn?) your own discretion.

Re:Somebody needs to buy... (0)

Anonymous Coward | about 3 months ago | (#47015577)

*bags, not backs , derp

Re:Somebody needs to buy... (4, Informative)

war4peace (1628283) | about 3 months ago | (#47015655)

How to microwave popcorn:
Put the bag in, turn microwave on. When number of pops/second goes down to 1, stop, pull bag out, enjoy results.

Re:Somebody needs to buy... (1)

AK Marc (707885) | about 3 months ago | (#47015767)

I've had a microwave where that would get you 3-4 tbsp (about 1/4 to 1/2 the bag) unpopped, and the popped parts black, charred and inedible. For my current microwave, that works.

Re:Somebody needs to buy... (0)

Anonymous Coward | about 3 months ago | (#47016183)

You should buy higher quality popcorn then. I have found the cheap crap like Act II does that, while the better stuff like Orville Redenbacher pops much more evenly.

Re:Somebody needs to buy... (1)

sumdumass (711423) | about 3 months ago | (#47017539)

I was wondering if you knew that you didn't even need to get the microwave popcorn. Just get regular popcorn and put some in a brown paper sack (the lunch sacks work well) and follow the pop until a few kernels per second rule.

You can even flavor it in the bag. I like adding a table spoon of diced green chilis from a can, a sprinkly of salt and cyanne pepper dust, and a little butter before poping.

Re:Somebody needs to buy... (0)

Anonymous Coward | about 3 months ago | (#47015777)

If I try that in my microwave above about 70% power, the sugar and butter in the packet wil catch fire long before even half the kernals have popped yet most packets say microwave on full power for 2 minutes.

Re:Somebody needs to buy... (1)

war4peace (1628283) | about 3 months ago | (#47017309)

Forgot to mention: always use 100% power to maximize heat spread.

Re:Somebody needs to buy... (0)

Anonymous Coward | about 3 months ago | (#47015669)

In my experience, popcorn is super easy, if you pay attention. You must stand and wait while it pops. When the popping slows down, start to count the seconds in between pops. Once you have 1 pop every two seconds, you are done. The only problem is that the amount of time between "done" and "everything smells like smoke" is a very short amount of time. That is why you shouldn't even try to get every last kernel to pop. These instructions work across any brand of microwave popcorn, so it actually would be cool if the microwave had a little microphone inside to count the pops per second. Then the "popcorn" button would actually work.

Re:Somebody needs to buy... (4, Funny)

NotDrWho (3543773) | about 3 months ago | (#47016655)

Fuck it. Too much work. I'll just eat this tube of cake frosting instead.

Re:Somebody needs to buy... (0)

smooth wombat (796938) | about 3 months ago | (#47016687)

You must stand and wait while it pops.

This is Slashdot where the majority of people are OCD and can't stand still for 2 minutes because they are so busy with everything else. They would literally explode before the popcorn does if they couldn't run away and chimp their phone or play a game or pretend their life was so important and announce it to the world.

You might as well ask a baby not to poop while you're holding it.

Re:Somebody needs to buy... (1)

omnichad (1198475) | about 3 months ago | (#47017095)

Just underpop it every time. Not only will it not be burnt, but if you stop it early enough you also get less-dry popcorn. Cooking to the last pop takes out every bit of moisture (and you can taste the difference). If that's not enough, pop 2 bags.

Re:Somebody needs to buy... (1)

pr0fessor (1940368) | about 3 months ago | (#47017287)

My old microwave used to burn the popcorn, then it died.. I purchased a new one that does it right given you can figure out how many ounces are in the bag.

I don't have any problem with hot pockets mostly because if I'm going to have a hotpocket at lunch I pull it out of the freezer in the morning before work and stick it in the refrigerator. It's mostly thawed out by lunch when I pop it in the microwave.

Re:Somebody needs to buy... (3, Interesting)

TapeCutter (624760) | about 3 months ago | (#47015787)

Hmmm, my MW is 1100 watts. For frozen meat pies (Australia's national dish), heat for 1min, stand for 5min, heat for 1min, stand for 2min, it comes out like a warm pie from the bakery. However if I heat for 2min straight, the outside is hot, the centre is frozen, and the pastry has turned into something that would be suitable for re-treading tyres. Thermal inertia explains the frozen centre, but I'm neither a cook or chemist so I have no idea why the pastry turns to rubber?

Re:Somebody needs to buy... (1)

L4t3r4lu5 (1216702) | about 3 months ago | (#47016069)

Ever seen a microwave oven with the words "CHAOS defrost" written on it?

Your microwave outputs at a standard rate; A percentage of the full 1.1KW output for the time you have specified. Microwaves work by exciting water to boiling point extremely quickly, and in that absorbing the microwave energy. You put your pie in for two minutes straight and the outside of the food will be utterly ruined, having absorbed the entire X/1100 you threw at it. Leaving the pie to cool in between allows the food around the bit that's just heated to reach equilibrium; It heats up while the microwave isn't on, just by drawing away (sorry, physics types) the energy from the water that was just heated.

CHAOS defrost gets around this problem by switching the output of the microwave during the cycle, down to allow the outside to cool a little, then back up to keep the process continuing.

The pastry turns to rubber because it's been boiled dry by the microwave; You've dumped the whole of the cooking cycle into the very outside of the pie in a very short time. Leaving it to cool for 5 minutes allows that heat to warm the middle, getting you a better result.

Re:Somebody needs to buy... (0)

Anonymous Coward | about 3 months ago | (#47016305)

On my microwave it is called "Turbo Inverter" Defrost, which my parents also have and showed them how to use last night actually.

Re:Somebody needs to buy... (1)

NotDrWho (3543773) | about 3 months ago | (#47016707)

You can get a similar effect by adjusting the "power level" on the microwave. Usually this doesn't actually lower the power level, it just cuts it on and off a percentage of the time. For example, on my microwave power level "10" is full force (High). Power level 5 (50%) will cook on high for a 30 seconds, then switch off entirely for the next 30 seconds, then back on again for 30 seconds, etc.

Re:Somebody needs to buy... (1)

omnichad (1198475) | about 3 months ago | (#47017121)

Not just "usually". I think it's in every case but Panasonic. I don't know of anyone else using an actual inverter to adjust the output voltage.

Re:Somebody needs to buy... (0)

Anonymous Coward | about 3 months ago | (#47016891)

As pointed out by other posts, you've over cooked the pastry and have made it tough. The important difference is that microwaves heat frozen stuff a lot less efficiency than any thing not frozen with water in it. So if you try to blast through defrosting something, you get pockets of areas that start to defrost, then they start absorbing a large amount of the power while the frozen parts still are not getting much. The areas that defrost first get way too much heating.

Re:Somebody needs to buy... (1)

NotDrWho (3543773) | about 3 months ago | (#47016609)

I've found that with microwave cooking, the implied (but all-too-often unwritten) instruction is to let the food sit for a while before you actually try to eat it. With two Hot Pockets, you cook them for 3 min 30 sec. Then (not mentioned in the instructions), you need to let them sit for about 10-15 minutes. If you were foolish enough to try to eat them right out of the oven, your mouth and throat would probably be incinerated into a fine ashy substance.

I'm not sure why so few microwave instructions don't mention letting the food sit after being cooked. Maybe because they're afraid it would scare away customers if they knew they couldn't have their Hot Pockets RIGHT GODDAMNED NOW! Or maybe they want to keep up that "Ready to eat in just 2 minutes!" fiction on the box. But then again, I also never figured out why McDonalds used to feel the need to give you a cup of coffee that was BOILING hot (until their infamous lawsuit).

Re:Somebody needs to buy... (2)

camperdave (969942) | about 3 months ago | (#47017399)

you cook them for 3 min 30 sec

You cook them for 3 min, 30 seconds? Try 3 minutes 33 seconds. Your finger is already on the 3 key. Why waste the seek time needed to bring it to the 0 key? Or try a 3:21 swipe. 3 min, 30 seconds - Who's got that kind of time?

Also, do not be afraid to explore the posibilities of 77, 88, or 99 second cook times.

Re:Somebody needs to buy... (2)

Greyfox (87712) | about 3 months ago | (#47017427)

You gotta let those fuckers cool off for a couple of minutes, until the gooey center of liquid hot magma cools down. Third degree tongue burns are no fun!

learn the tools you use (3, Funny)

HybridST (894157) | about 3 months ago | (#47015295)

Most microwaves have a power control. 90 seconds at power 2 or 3, wait 1 minute. Flip, 1 minute at full power. Wait 3 minutes. Serve.

There exist websites and books devoted to this appliance and how to use it correctly. This is a non-story.

Caveat: there are some nice physics going on in the explanation but only for the layman. Look elsewhere for the gritty detail we /.ers are used to seeing.

Re: learn the tools you use (0)

Anonymous Coward | about 3 months ago | (#47015383)

Indeed! Leftovers on half or third power for 7 minutes. Stir. Serve. They used to make crown roasts in these and if modulated correctly one can cook fairly decently.

Re:learn the tools you use (3, Interesting)

toejam13 (958243) | about 3 months ago | (#47015423)

Agreed. I rarely microwave my food with a power duty cycle level higher than 70%. You need those few seconds of rest for the heat to evenly distribute inside your food.

For frozen stuff, I usually set it to 50% so that the outside doesn't overcook. Takes longer, but not as long as a regular oven.

Ovens. Get rid of them. (0)

Anonymous Coward | about 3 months ago | (#47015843)

This. This very much so.

Once you learn how a microwave DOESN'T work, you can begin to use it correctly.
And when you do learn how to use it correctly, even the ready-meal generation of foods will cook brilliantly.

I literally haven't used an oven in years.
You can cook anything in microwaves as long as you Do It Right. And if you get a good solid microwave, it will last you for years. A nice big one at that.
You gotta play with the heat settings. Experiment a little, see how your microwave cooks dense and light foods.
Now half the power settings and see how it does. Compare the two and see how you can combine low and high powers to produce something that is both cooked and crispy.
And funnily enough, many of those ideas used for a microwave will also considerably speed up cooking in an oven as well.
The biggest of these is cutting meat up in to smaller pieces so they absorb more heat. Some purists will wank over how they put a whole chicken/turkey in the oven with stuffing and be ready in so many hours. Meanwhile smart people will say "screw this traditional nonsense", slice it up, maybe even shred it, add some stuffing on top it, or even some of it if some don't like it, it is considerably more customizable this way, then be done in less than half the time.
The one bit where that does fall apart is cooking one lump of meat to different levels of being cooked. But that is exactly where the microwave prevails! We just came full circle.
Ovens. Get rid of them.

Re: Ovens. Get rid of them. (1)

Anonymous Coward | about 3 months ago | (#47016281)

You are kidding right? Cooking raw meat in the microwave is probably the most disgusting thing I've heard (I'm gagging at the thought).

Microwaves are useful for heating small amounts of water, and that is about it. They destroy/alter the texture and taste of food to the point of being uneditable.

Yes, I am a microwave hater.

Re: Ovens. Get rid of them. (1)

NoImNotNineVolt (832851) | about 3 months ago | (#47017339)

Microwave bacon.

Seriously. This coming from a bacon lover who saved the rendered bacon lard from all his bacon frying adventures. Once you go microwave bacon, you never go back. Perfectly crispy every time.

But you don't get to save all the bacon lard, unfortunately. Good thing I still have a solid 8 oz. left from my frying days.

Re: Ovens. Get rid of them. (1)

hendrips (2722525) | about 3 months ago | (#47017623)

I'll second that statement. Microwaving is especially nice for me because I can make the bacon crispy without having to char it, which was always my pet peeve about bacon.

Re: Ovens. Get rid of them. (1)

ferret4 (459105) | about 3 months ago | (#47016665)

When you've finished tearing your meat to shreds, why not add it to a chemical bath to leech out the nutrients while turning the remainder into shit? Smart people can just suck the juice of life up a straw from around the turds, while the morons out there can pretend they're enjoying their 'meals'.

Re:Ovens. Get rid of them. (0)

Anonymous Coward | about 3 months ago | (#47016849)

it is considerably more customizable this way, then be done in less than half the time.

It is odd to advocate a reduction of options as being more customizable. However customizable using a microwave oven is would still be less options than owning both an oven and a microwave (or a microwave oven with convection built in for those with limited space). Maybe sometimes we don't want meat that is shredded, or want to make something like bread or pastries that are bigger than the size evenly heated by a microwave, or want to cook something that does better with a long, slow heating, or want a crispy outside and moist inside. And it is not like the extra time is that big of a deal, since while something is sitting in the oven or microwave, the person cooking can go do other things.

It also just seems weird for a geek to advocate using fewer tools instead of the right tool for the right job. If situations limit your tool selection, whether due to costs, time, or space, sure, there is a lot you can do with fewer tools and a lot you can learn from trying to better use a single tool. But that is different than suggesting to avoid or get rid of a tool you may already have, or suggesting that there are no uses for a different too or ways to optimize when you have a choice in tools.

So it does take a whopping two hours for me to cook a whole turkey in the oven, and if it is a week day that I have to cook something after getting home late from work I will chose something that can be done in the microwave. But on a weekend when I have time to start early, I'll chose the oven every time for the turkey even though I've cooked turkey from raw in a microwave before. And I wouldn't gain any extra time by using a microwave in those cases, because I would be doing something else for those two hours, either way needing about ten minutes of prep work.

Re:Ovens. Get rid of them. (0)

Anonymous Coward | about 3 months ago | (#47017075)

Just an aside, the stuffing people are public nuisances, you need to get stuffing to 165 to get rid of the raw turkey juices it is exposed to. To get it to 165 while inside the turkey requires cooking the entire bird until the slow cooking dark meat is overdone and the fast cooking white meat is burned and cracked jerky like substance. If you cook until the turkey meat is ready, you are serving still raw meat juices in the stuffing.

Cook the stuffing outside the bird for everyone's sake food poisoning should not be a family tradition.

Re:Ovens. Get rid of them. (0)

Anonymous Coward | about 3 months ago | (#47017511)

You can preheat the stuffing, which can actually help the turkey cook more thoroughly if done just right. It helps a lot if you have water proof oven mitts (like some of the silicone ones) for stuffing the turkey while the stuff in is hot. Or you can stuff the turkey with stuff that you don't plan to eat and still get some of the flavor benefit to the turkey (e.g. head of garlic and some bunches of herbs, or some dried fruit).

Re:learn the tools you use (0)

Anonymous Coward | about 3 months ago | (#47015565)

Power level 2 on my microwave is pretty much for slow defrosting only. If I followed your directions, I'd either chip a tooth or suck on it for a long time.
 
That said, I used to eat way too many Hot Pockets (well, Lean Pockets) and literally never had an uneven heating problem with them. Maybe the difference is if you actually follow the directions and let them sit after heating.

Seriously. (4, Funny)

adolf (21054) | about 3 months ago | (#47015303)

I've never had a problem with Hot Pockets: Follow directions, learn how it works in a given microwave oven, and...done: Ridiculously-hot cheap, bubbly, unhealthy goodness.

Meanwhile, I don't need to read TFA to learn how the powdered aluminum wrapper turns RF energy into thermal energy. And I don't need TFA to know that any thing has a certain reluctance toward changing temperatures, as nothing is a perfect thermal conductor.

In fact: Dude, I've been cooking with a microwave since I was a little kid: It was the first kitchen appliance I was certified on other than -- maybe -- an electric can opener.

Up next on /.: How shoelaces work to keep our shoes on our feet, followed by a lesson in using a light switch to illuminate a dark room. Or "Toast: Why bread is caramelized only on the outside when using the every-day toaster."

*head in hands*

Re:Seriously. (0)

Anonymous Coward | about 3 months ago | (#47015363)

Up next on /.: How shoelaces work to keep our shoes on our feet, followed by a lesson in using a light switch to illuminate a dark room. Or "Toast: Why bread is caramelized only on the outside when using the every-day toaster."

Tides go in, tides go out. Like clockwork. Explain that!

Re:Seriously. (2)

DarwinSurvivor (1752106) | about 3 months ago | (#47015607)

How shoelaces work to keep our shoes on our feet

Ted already did that one [ted.com] .

Re:Seriously. (1)

Stormwatch (703920) | about 3 months ago | (#47015643)

Someone mod that up, please! That was very informative, I've been tying my shoes wrong all my life!

Re:Seriously. (1)

Kuroji (990107) | about 3 months ago | (#47015689)

Really? Have your shoes not been staying tied when you tie them? Have they been constantly catching on anything you walk past since you were able to tie them yourself?

No?

Then maybe everyone should stop praising this talk as the goddamn second coming.

Re:Seriously. (0)

Anonymous Coward | about 3 months ago | (#47015955)

I've had some trouble keeping my shoelaces tied for about an hour or so. A friend made a snarky comment in the lines of "No wonder. You're wearing [well-known shoe brand], their laces suck" and since then I've bought a new pair of shoes of a different brand and their laces stay tied.

I even tried that TED trick which I wasn't too sure of, mostly because I'm left-handed so my knots are already different.... maybe that's the reason.

I'm guessing it's something about the materials and coating of the laces, mixed with how each person makes their knots, with a little of how your foot moves inside the shoe...it all adds up to different rates of slipage, and some shoes will stay tied all day long, while others last only a few hours.

IDK, only from my own experience.

Re:Under-engineered footwear (1)

hoboroadie (1726896) | about 3 months ago | (#47017545)

Part of the problem is that those shoes also don't last long enough to earn after-market laces. I have replaced original-equipment faux laces on new shoes with good results.

Re:Seriously. (1)

DarwinSurvivor (1752106) | about 3 months ago | (#47016231)

To be fair, sandals didn't have laces for his supposed first time around.

Re:Seriously. (1)

oobayly (1056050) | about 3 months ago | (#47016047)

Interesting, I'd never really looked at the knot I use to tie my laces - it turns out I've been doing it "correctly". So I had a look at the resulting knot - the correct way results in what looks like a Reef Knot [google.co.uk] whereas the incorrect way ends in a "granny knot" (I'll have to find the etymology of that one).

Odds are, I managed to do it correctly because of years of having to tie knots with cold water being dumped over me, a sailing flapping in my face, trying to steady myself on a deck at a 40 degree and with a tactician shouting "hurry up" because he gave me 45 seconds to change a sail. It turns out that I now struggle to tie knots while looking at them.

Re:Seriously. (1)

DarwinSurvivor (1752106) | about 3 months ago | (#47016225)

My shoes were by far the first knot I ever learned to tie. I then became very good at tying knots in scouts (I can tie a bowline around my waist with 1 hand). It wasn't until I watched the video that I actually bothered to look at the knot I'd been tying everyday from muscle memory and realized it was a granny knot. The instant I actually looked at the knot on my shoe I knew it was wrong, I just never looked at the damn thing for 20+ years!

Re:Seriously. (1)

Reapy (688651) | about 3 months ago | (#47017567)

Tying my shoes is the only knot I know how to tie, I guess I was lucky in that I was taught the 'right' way the first time. After watching the video I ended up tying my shoes wrong trying to reverse what I normally did.

Re:Seriously. (0)

Anonymous Coward | about 3 months ago | (#47015387)

You sir are a fine example of right.

Re:Seriously. (1)

Jmc23 (2353706) | about 3 months ago | (#47015395)

Dude, I've been cooking with a microwave since I was a little kid.

n.b. this is not something to be proud of, but hey if you can't tell the difference, kudos to you.

Re:Seriously. (1)

Anonymous Coward | about 3 months ago | (#47015407)

Normally a microwave cooks things from the inside out, because it transfers energy directly to the water molecules. In other words, normal microwave operation has very little to do with thermal conduction.

However, microwaves don't cook ice because the ice crystal lattice prevents the frozen water molecules from resonating at 2.45 GHz, which means very little microwave energy is transferred into to ice. Thus frozen foots rely on on thermal conduction.

Tip #1: Try HybridST's suggestion of using 90 seconds at low power, or try putting it in a ziplock bag and letting it thaw in warm water for a few minutes. This will dramatically improve the effectiveness of the microwave.

Tip #2: Cut a 1/8" thick strip of cardboard and bend it into a zigzag Z pattern. Use that as an air gap inside the crisping sleeve under the hot pocket; it will prevent the soggies.

Re: Seriously. (0)

Anonymous Coward | about 3 months ago | (#47015415)

Science!

Re:Seriously. (1)

Hognoxious (631665) | about 3 months ago | (#47015589)

Normally a microwave cooks things from the inside out

That's what they said when they first hit the market. It was bollocks then and it's bollocks now.

it transfers energy directly to the water molecules.

But not to the ones on the outside, presumably.

Re:Seriously. (0)

Anonymous Coward | about 3 months ago | (#47016217)

Why is this modded up up bit not its parent?
The fact is, if you let chicken thaw for a few minutes, it cooks all the way through, although the outside will cook a little slower because it loses heat to the environment. Everyone who has ever owned a microwave can attest to this.
And if you have a combi-microwave you can even get your chicken golden-brown and crispy on the outside.

Re:Seriously. (0)

Anonymous Coward | about 3 months ago | (#47016721)

Normally a microwave cooks things from the inside out, because it transfers energy directly to the water molecules.

It isn't so much from the inside out, as for thin things it heats evenly and the outside loses more heat to the air and environment. If you cook something more than a couple centimeters thick with a decent amount of water, you start to get enough attenuation that the inside gets heated less than the outside.

resonating at 2.45 GHz

It is not a resonance. The 2.45 GHz frequency was chosen somewhat arbitrary, as a combination of being practical to make electronics for and because a band of the radio spectrum had to be set aside for industrial uses to allow for heating applications. There are industrial microwave ovens that operate at 900 MHz because it is easier to make large, high power equipment at lower frequency. The higher frequencies are more efficient at heating, with a peak of around 7 GHz for near boiling water and a peak of near 100 GHz for near freezing water.

It is still correct that frozen water does not get heated very well by microwaves, but "resonance" is the wrong word to use.

Re:Seriously. (1)

darkonc (47285) | about 3 months ago | (#47016233)

If you don't have a problem with Hot Pockets, then you probably have a freezer section that borderline doesn't work. If a hot-pocket is nearly thawed when you throw it into the microwave, it will have pockets of semi-liquid that quickly heat up and help to thaw the internals which then heat up nicely. It doesn't have a whole lot to do with the power of your microwave.

The other solution is to run the thing on 'defrost' for a couple of minutes -- (a short blast of microwaves every 10 seconds or so, with time for the recently-heated liquids to thaw the area around them)... then follow the normal directions to get a properly hot hot-pocket.

Re:Seriously. (1)

omnichad (1198475) | about 3 months ago | (#47017277)

If there were no fat in a hot pocket, then maybe I'd agree with you. As long as I put the pocket to the edge of the turntable instead of the middle, it comes out fine. I only cook at 60% power, but that's not enough change to fully defrost the water alone.

Re:Seriously. (0)

Anonymous Coward | about 3 months ago | (#47017407)

I can't wait to read those articles. The toaster oven baffles me.... seriously, stay in school kids, or don't and get a crappy job while I make societal changes to keep you at a crappy job....

That escalated quickly. Stupid people are examples of mistakes.

It's on purpose (4, Funny)

Rosco P. Coltrane (209368) | about 3 months ago | (#47015419)

Scalding on the outside and frozen inside is a feature: it's the Hot Pocket's way of telling you it really isn't proper nutrition.

Re:It's on purpose (0)

Anonymous Coward | about 3 months ago | (#47016123)

Nutrition for the soul, so it can leave the body quicker.

Penetration of microwaves (1)

countach (534280) | about 3 months ago | (#47015431)

I always assumed it was something to do with losing energy as the microwaves penetrated the substance, and I don't see how this explanation really changes that. After all, when the pocket comes out of the freezer it is ALL frozen. OK, so frozen stuff doesn't microwave easily, but then why does the outside heat first? My intuitive thought that the microwaves don't penetrate as well seems unrefuted.

Re:Penetration of microwaves (1)

WhiteZook (3647835) | about 3 months ago | (#47015457)

The outside layer of molecules in the crystal lattice have a bit more freedom to wiggle, so they'll heat up quicker in the microwave. Also, the outside layer is in contact with the air, so that also helps to thaw it.

Re:Penetration of microwaves (2)

Deadstick (535032) | about 3 months ago | (#47016793)

OK, so frozen stuff doesn't microwave easily, but then why does the outside heat first?

When a wave penetrates a conducting medium, it transfers energy into the medium, and as a result it gets weaker exponentially. The intensity vs. depth is given by

E=Ei*exp[-C(depth/wavelength)]

where Ei is the intensity at the surface, and C is a constant that depends on the characteristics of the medium. C is small in ice, so the wave doesn't transfer much energy initially, and most of the energy just trucks on through and out the other side. Still, there is some attenuation, so the intensity is greatest at the surface and melting occurs there first.

As soon as that happens at the surface, C gets much larger and the liquid sucks most of the energy out, getting progressively hotter. The remaining energy again encounters ice, and has almost clear sailing until it hits the water on the other side, and again heats the water.

Thanks? (1)

jonyen (2633919) | about 3 months ago | (#47015447)

Well, now I understand why hot pockets stay frozen in the middle, but the article doesn't tell me what I can do to heat it up...

Re:Thanks? (0)

GrahamCox (741991) | about 3 months ago | (#47015517)

Don't bother; don't buy/eat that crap.

Re:Thanks? (1)

NoImNotNineVolt (832851) | about 3 months ago | (#47017445)

It's really not rocket science. You wait.

I know it can be difficult to restrain oneself when there's a parcel of gooey deliciousness sitting there, fumes of flavor enticing and tempting. But really, if you just wait approximately three minutes after it's out of the microwave, you'll find that the outside is still nice and toasty, but now the inside isn't some strange combination of lava and ice cubes. Let that heat distribution even out and your processed food product will be much more enjoyable.

Actually the physics of microwave heating (0)

Anonymous Coward | about 3 months ago | (#47015449)

Ever noticed when something is frozen (e.g. some minced meat) that the first little while defrosting does nothing, but at some point suddenly the outside edges are cooking?

Microwaves affect hot water and steam more than they affect cold water or ice. There's your physics.

And as someone mentioned there's a power control on microwaves, so that periodically the heat is allowed to spread into the food without putting more energy into the already hot bits.

Don't get me started on the shit choices of duty cycles though!

RTFM, why? (1)

VortexCortex (1117377) | about 3 months ago | (#47015453)

Hey, if idiots wrote it then RTFM is a bad idea, OK?

Simply keep the Hot Pockets in your fridge. Then place them in your toaster oven to cook them.

Ugh (1)

Misanthrope (49269) | about 3 months ago | (#47015473)

Jim Gaffigan sums up my feelings on Hot Pockets.
https://www.youtube.com/watch?... [youtube.com]

Re:Ugh (1)

drinkypoo (153816) | about 3 months ago | (#47016273)

I think Daniel Tosh did a better job of summing up my feelings on hot pockets, but it seems like Jim Gaffigan helped.

Re:Ugh (1)

rwise2112 (648849) | about 3 months ago | (#47017433)

Dr. Evil has a different opinion: "Have you tried the Hot Pockets? They're breathtaking!"

I just wish (0)

Anonymous Coward | about 3 months ago | (#47015499)

I just wish there was a blog - probably most appropriately titled Ends With A Bang - that explains the bathroom devastation that occurs after eating one.

US-centric (0)

Anonymous Coward | about 3 months ago | (#47015557)

Could we please have some news that isn't so amazingly US-centric for a fucking change? There's more things happening in the world than in pathetic US-of-A. Provide some variety of topics ffs. I best the next story will be about Comcast or Netflix or some shit.

Re:US-centric (1)

Dins (2538550) | about 3 months ago | (#47016817)

So submit an article!

I "airwave" frozen food lately. (2)

Maxo-Texas (864189) | about 3 months ago | (#47015641)

I know I'm going to eat a frozen dinner so I sit it on the counter for 10 minutes before i heat it. They heat up evenly and faster.

I also nuke for a 15% longer but at 80% power.

Of course, I also gussy frozen food up too. Adding just a teeny bit of herbs, or sour cream, more vegetables or some fresh cheese can make them quite tasty.

Re:I "airwave" frozen food lately. (0)

Anonymous Coward | about 3 months ago | (#47017341)

A true microwave gourmet! I never thought I would see the day..

Wow that guy is a great writer! (0)

Anonymous Coward | about 3 months ago | (#47015685)

Wow that guy is a great writer! I'd like to write more but I just got a warning that the Internet Exclamation Mark Hopper is running low on exclamation marks for some reason!

Utterly wrong explanation (-1)

Anonymous Coward | about 3 months ago | (#47015891)

I don't know where this "rotating water molecule" crap came from, but it's not the way microwave ovens work. The wavelength of a 2.5GHz RF wave is about a FOOT, not the width of a water molecule as the drawing implies.

Here's a test for you: ever notice that a fly in the microwave survives? Why is this?

Simple: microwave ovens simply induce massive current and cause Joule effect heating. But only on objects near the size of the RF wavelength. The explanation is in the article itself:

"What you do is you take a thin film of metal that can absorb the electromagnetic (microwave) radiation and convert it to heat"

Look, the EM wavefront doesn't "know" what the hell is in front of it, it doesn't "do" one thing to water and another to metal. It's ALWAYS induced current.

There's nothing magical about the frequency the magnetron uses, it's just a compromise between what's legally available in the spectrum and what's easy and cheap to build. It could have worked at 2.0 or 3.0 GHz too.

So why does the center stay cool?

Simple too. The eddy currents behave that way!

http://en.wikipedia.org/wiki/E... [wikipedia.org]

And don't even get me started on the whole "infrared is heat" thing...

Re:Utterly wrong explanation (1)

Alioth (221270) | about 3 months ago | (#47016157)

[citation needed]

I've never seen the explanation for how a microwave works written as in your message until today. All the explanations I've seen are what's stated in the article; so I think it's your explanation that's wrong for how microwave ovens heat water.

Re: Utterly wrong explanation (0)

Anonymous Coward | about 3 months ago | (#47016209)

He is right [RF engineer here] and the article is flat out wrong, along with all the other crud about water resonance. Yeah, water is resonant, but nowhere near 2.45 GHz. And they don't cook from the inside out. It's just the normal skin effect from a lousy conductor that allows the currents to penetrate deeper. Microwaves are also used for metal-ceramic sintering, and other industrial heating, along with 13.56 MHz. Those frequencies are ISM band; no specific resonance.

Re:Utterly wrong explanation (0)

Anonymous Coward | about 3 months ago | (#47016635)

microwave ovens simply induce massive current and cause Joule effect heating. But only on objects near the size of the RF wavelength. The explanation is in the article itself:

This is not correct, because you can easily microwave things much smaller than the wavelength. And if your microwave is old or crappy enough to set up a standing wave instead of having a decent stirrer, you get get hot and cold spots corresponding to the nodes in the standing wave, instead of any heating from current sloshing back and forth.

The heating in a microwave comes from dielectric heating, which is basically directly shaking the water molecules. It has nothing to do with resonance, but it still is a moving of the water molecules by electric field. Even though they are much smaller than the wavelength, they can still couple to the RF field. It is not the same as an antenna which would be in efficient at the size, and to something on the scale of a molecule, the RF field looks effectively like a DC field at any given point, but that is all that is needed.

Gaffigan (1)

ThatsNotPudding (1045640) | about 3 months ago | (#47016191)

"We offer a Hot Pocket; the outside is boiling lava-hot and the inside is frozen solid."
"Will it burn the roof of my mouth?"
"Oh, it will destroy it. Everything will take like plastic for a week."
"I'll have the Hot Pocket."

Try 3 minutes, without the sleeve. (1)

CronoCloud (590650) | about 3 months ago | (#47016755)

1100 watt oven 3 minutes 10 seconds, without the crisping sleeve, on a paper plate, on the outside of the turntable. Let cool for a minute, or two, Eat. Better tasting fillng that way too.

Old news (1)

YoungManKlaus (2773165) | about 3 months ago | (#47016893)

you learn that in physics classes normally

Author must be doing it wrong (1)

Nimey (114278) | about 3 months ago | (#47017313)

I used to eat 3-4 Lean Pockets a week, so I've got a pretty good idea what I'm talking about: I've never had the problem he describes with the outer portions being lava-hot but the center being frozen. This has been so across 3 different microwave ovens, one of which was an ancient late-'80s unit made when turntables were a premium feature and you set the time with a dial.

My secret? Following the goddamn directions on the box and adjusting for the microwave's rated power. The directions are usually for a 1000 Watt microwave (some products calibrate for 1100W for some reason). That's what my current unit is, so that's easy. If the microwave is 900W, you nuke the food for 10% longer, so if the directions call for 3.5 minutes you convert that to seconds (210) and add 10% (21), giving 231, then convert that back to minutes and seconds, which is what the microwave groks (3 min 51 sec). Stupid easy.

I have had the author's described problems when heating up leftovers, especially stews.

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