It's codswallop.

You have obviously never cooked with an induction hob!! I will be replying to the main Blog in a minute as we have been cooking with induction for 2 years, absolutely fantastic, better than all the other hob types that I have ever used.....

Have a great day!

You can pretty much believe what you read. Of course they may exagerate the overall benifits against gas or electric coils, but for the most part they are exceptional. However you may need to buy new pots if they are not compatable with your new rangetop. You can set them to simmer and forget them. The entire pot becomes the heater not just where the gas or element comes in contact with the pot creating hot spots. They are more expensive to buy but your wife will love how easy they clean up. One warning though. They will shut off when you remove the pot. However, do not place a metal spoon or other object on the surface. They may just activate and cause a very severe burn.

Interesting (especially the contrast between your response and PW's). Obviously this kind of cooktop would render glass and ceramic useless. What kinds of metal pots do they recommend/work with?

Of course I just recently bought one of the glass flat cooktops, and find it really slow to heat, although it looks red hot quite quickly.

I'll be interested in comments from others...

Dick

You will not find me (Ex Chef) in front of one. You will find others that try to keep them clean after use. You must have received a scraper with your new oven/gadget. Why did they make it so hard to clean the flat top? Then introduce a cleaning device which was never needed before. The only way to keep it clean is not to cook at all. Completely impractical. It must be some useless byproduct from the space industry. They could be recycling R&D gone wrong. For sure they never consulted a house wife or every day cook. "Induction" is a smart word to confuse the ill informed. It induces only thoughts of the past when a gas flame could be instantly and precisely regulated. These stoves are more like a light show, with heating elements attached, if you ask me.

Microwave 8 out of 10

Induction cooking 1 out of 10,

where the 1 stands for "very pretty to look at when clean and not in use". They should be out lawed. The good thing is they will not be around for a long time anyway, so there is no problem really. Well, another problem is that well timed cooking goes down the drain. Go Gas. Ky.

Ky

I have the impression that most of your message was directed at the kind of cooktop I pruchased recently, a GE 'Profile' Glass flat cooktop. This device uses ordinary heating coils under the glass surface, or perhaps embedded in it. It does have the advantage that spilled liquids don't accumulate in the pans under the burners, like my previous electric ones. But as you indicate, You have to clean it every time you use it - this is a pain! And it is vvveeeerrrryyy slow to heat a big pot of water.

I haven't yet seen one (nor even an ad for one - but I rarely watch TV), but I am assuming (admittedly dangerous!) that when they refer to induction cooking, they are talking about a device that has AC magnetic coils, not heating coils. The AC magnetic field would induce eddy currents in any metallic pot or pan placed in the magnetic field, and those currents would heat the pot. I think this would work best in fairly thick pots, and there is probably an ideal frequency for the AC. I suspect that the ideal frequency is significantly higher than 50 or 60Hz. There would also be a difference according to the conductivity and magnetic properties of the pot - That's why I was asking what kind of pots were recommended. The recent advances in Variable Frequency Drives for motors and Pulse-Width Modulation in general make all sorts of possibilities that weren't practical a few years ago...

I remain interested in the comments, and hopefully experiences, of others.

Dick

Thanks Haajee!

I don't understand why you marked your comment as 'off-topic"! It is NOT!

I had not seen that thread. I copied your URL and pasted it into my browser. If you don't know how to make the URL into a clickable link, say so and I'll show you.

This verifies most of my assumptions about induction cooking, BUT:

1. The author of the (much appreciated) site shows a poor understanding of frequency: although he recognizes the difference between power line frequencies and induction frequencies, he seems to associate induction frequencies, which I gather are in the 10-50kHz range, with cellphones, which are generally in the 2-3GHz range, and microwave ovens, which I believe are all at 2.45Ghz. There is a huge difference between the range and effects on human tissue between 50kHz and 2 or 3 GHz! Although the 50kHz has a longer range, it has no ionizing potential, as does 2Ghz.

2. I was somewhat surprised to find they specify ferromagnetic pots. Whenever I think of eddy currents, I automatically think of aluminum (the aluminum wheel in a kWh meter; the aluminum eddy-current disk used to slow down phonographs), or transformer/motor core laminations, where thin insulated sheets are used to reduce eddy currents.

I'm still interested in learning more about this technology!

Dick

" 1. I don't understand why you marked your comment as 'off-topic"! It is NOT!

2. ..If you don't know how to make the URL into a click-able link, say so and I'll show you."

1. Actually I thought that some posts are marked for it. And got only one way to click it.
May be my browser not showing full format of Reply print-in space.
Actually I was also searching for gradings for other participants.

2. I intentionally avoid "to make the URL into a click-able link" as I have requested a number of times to give full URL in text as only I-Explorer only copies URL for text-editor. And I miss most of the links due to my browser which copies plain text.
As ISPs services here is not good & frequent Power outings make it more adverse, I have to copy the text & review off-line.
Even XP's Wordpad does not copy the link [in text as full URL] & keeps as link only if saved as .doc or .rtf.
I use "Wordpad" of windows 98SE as text editor to copy the link as full url.

Thanks a lot for your offer & regards for your courtesy .

OK, I understand.

Have you tried FireFox? I'm a Mac Guy, as you know, and would prefer to use Safari, the built-in Mac Browser. But for whatever reason, CR4 does not work well with Safari, so I had to switch to FireFox. It does work well with CR4. FireFox is free, so give it a try...

At the bottom of the Reply editor, and just above the "Preview Comment" button, there is a box to check if your reply is "off-topic". you might have to scroll down to see it. Perhaps you accidentally clicked on it as you were moving down to the "Preview Comment" button.

Dick

Yes.

I am using side by side I-Explorer & FireFox. I use it for normal browsing & discussion groups. As I told in my post in your reply.

Some years back it was quite fast but due to plug-inns it installs without notice now not faster than IExplorer.

Still a good browser as it has TABs & your Task-bar [I do-not what it is in Mac] is not congested. IExplorer ver 7 has now added Tabs but not matured.

You will sure enjoy it as it is also for Mac.

Regards

There seems to be some serious misunderstanding in this blog about home induction cooking by many people, I will try and correct some of them for you as we have had induction top(s) for over 2 years, and all I can say is that there is nothing better in any respect!! We have gas in the caravan, and have had several types of electric hob over the years....

1) Induction cooking pots and pans must be magnetic, in so far that a magnet must stick to the bottom, which is why I carry a tiny magnet around when we are shopping for a new pan or something similar. There are I am told some Aluminium pans with a piece of steel sandwiched in the bottom, I have not seen them as of now. These will also work on an induction hob of course.

2a) The induction hob senses the size of the pot or pan and switches the coils on appropriately for that pan.

2b)The pan can (at least with our hob) be heated on one of 10 positions power wise, or it can be heated to one of 10 temperatures between 80°C and 280°C, selectable. It can also be switched on for a specific time, up to 180 minutes, with either a power or temperature selection. I am told that there are some new ones (built in only) that will sense where a pan is anywhere on the whole induction hob area and will heat it at any position you wish.....I have not seen them as of now, so I cannot comment further, but the technology is still progressing!

3) It is faster than even gas with switching on, this is also a function of the "ring" itself as these vary from a max of 1.4 KW to 2.4KW in maximum power in my experience. 2.4 KW is very very fast...

4) Switching off with regards to the energy is of course instant and removes heat even quicker than gas, as with induction, ONLY the pot gets hot, the hob itself gets slightly warm from contact with the pan, but is not itself heated, you would not burn yourself on it for example, even if you had been frying just before, it would just be warm enough to be uncomfortable. Even with gas, the burner gets very hot in use and can continue to heat water for a minute of two in at a low level (we have gas in our caravan) and you certainly cannot touch the surface of any other electric hob or gas just after switching off, so safer for children.

5) The hob senses if a pot (of the correct type) is on it and if the pot is removed, switches into standby mode and tells you it has done that. If the pot is not replaced within 15 - 20 seconds, it switches itself off completely, no forgetting a switched on ring and no damage will occur to anything either....

6) If a hob is switched on with no proper pot on it, it goes immediately into standby mode and switches off after 15 - 20 seconds.

7) The surface of the hob is of some heat resistant sort of extra hard plastic or some are glass, all very easy to clean with no mechanical help as nothing "Boils" on so to say, a wet cloth will get rid of all spills, even in the middle of cooking, with no danger of getting a burn.

8) When frying, you can place a sheet of newspaper on the hob, place the frying pan on this and fry all you want, the fat or oil splashes get soaked up by the paper. When finished, the paper is not even brown where it was between hob and pan!!

9) We have found that most "good" modern cook pots are induction capable, but not all of the cheap ones....which is why I carry a magnet!

10) A good friend of mine, who was a French chef for many years, but now retired, was complaining that he could not get enough heat out of a normal (UK) gas cooker for some of his "daring" dishes. I gave him my "Test" single induction Hob, which I luckily had in our caravan at the time, and he is over the moon as he can now have the aggressive heat that he desires for these dishes.....(he uses cast iron pans, which of course are magnetic as well!)

11a) About the only negative aspect I have and it is not serious is that the electronics has a cooling fan, like a PC, underneath, that you can hear when cooking. Not loud, but at least you cannot forget that something is still being cooked within say 5 yards or so......it does not bother me, nor does it bother my wife.

11b) My wife (who uses it the most) loves the way things are boiling so quickly and that many dishes can be prepared in a much shorter time than before. For example, she boils the jacket potatoes for 25 minutes and then only gives them 10-15 minutes in the oven, perfect! In the oven alone, probably 1 1/4 hours after the oven got to temperature. With the water first method, some time can be allowed for oven pre-heating in the boiling time!

12) For safety reasons, I went all around the edges of a saucepan and a frying pan with the edge of a steel spoon, to see if there was any "leaking" of energy around the edges of the pans. Even when offset from the ring slightly I found that only when the edge of the spoon, was placed between the rounded bottom of the pan and the flat hob, in about the last 1/8" was the spoon edge warmed up. Outside of that area I found no warming of the spoon.

I do not believe that the frequencies used pose any health problems either, I am told they are around 50KHz.. Which if I remember correctly is lower than long wave is on the radio bands (150 kHz - 300 Khz)

Conclusions

1) No wasted energy, so electricity bills are lower. Less use of the oven helps as well.

2) With all other methods of cooking, especially gas, the kitchen gets heated too, in winter no problem, but in a hot summer!!! The induction method reduces severely the amount of heat that goes into the kitchen area, many times over.

3) We have gone for portable double hobs x 2 and a single (5 "Hot" plates), they can be placed anywhere where a work top is with a power socket and well away from the edge, so that little hands (Hans?) cannot play!! We only use the number we need at any one time, the rest sit in a drawer and do not clutter the work top. The kitchen (we are getting a new kitchen this month!) people were most surprised when we ordered our new kitchen with an eye level oven and grill but no hob!!!

4) Other than the slight fan noise, we have noted no other minus points, except of course that some people will need to replace pots and pans....a problem if you just bought new and expensive, but not induction.....!

5) As far as I can tell, there are no safety issues with the frequencies used and the fact that it runs very cool and little hands will find less to play with( the buttons are only seen from above, no knobs to play with on the front), make it a good choice if small children visit or live with you!!

6) The best thing since sliced bread so to say!!!

If I can answer any other questions for anyone, that will not be a problem....

Thanks Andy!

I just wish I had seen that a few months back! I was not even aware that induction cooking was available when I bought a new 'hob' (new term to me).

I had thought of the possibility of induction heating for cooking myself more than once in the last 10 or 20 years, but never did anything beyond thinking...

I'm going to have to investigate the portable ones...

Dick

Would appreciate knowing where, when you find them. I'm in the bay area.

Start looking on the web, here is one that I found:-

http://theinductionsite.com/

All in the USA. I bet there are many more.......

Vielen danke!

Andy already gave us a start...

Will do. If you find them before I do, Please post here!

Dick

Yesterday I finally got a chance to go shopping...

My local Home Depot has 4 models of induction cooktop, (2 sizes, 2 colors), all GE Profile (the same brand and line as my current electric coil cooktop) for between $2000 and $2500. No portable devices at all.

I went to half a dozen appliance places - either same story or nothing available. One guy did tell me of a place he thought had a used Portable - he should call today...

I did finally find one single portable induction cooker at a high-end gift shop. I neglected to write down the brand, but I'm pretty sure it was European. It was a speckled black, and had HOT in six or eight languages written in a circle around the heating area. The Price was $598!

I guess I'll have to buy on the internet. Following Andy's links, I did find a couple of references for one around $150 . I'm a little leery of buying on ebay, but I'll do a little more research before I buy.

Dick

Don't be silly, buy on ebay from a company, you could have 4 or 5 for the $150 !!! Even if someone is not trustworthy, you can only lose max $40 that way!!

I buy fairly regularly on ebay, never from badly rated people, and up to now, I have not lost my money. My worst buy were 4 cheap bike racks that were far more used than said, but I got all 4 for less that €40, so who's complaining!!!

Send me an email (bob.bryant@valent.com) and I'll send you some links for domestic retail. The new Supenden (sp?) units come with a free piece of cookware too.

I'm seeing ebay units starting at around $30. Hard to believe shipping could do that much to the price?

I've bought from ebay without regrets!

OK - I'm done for now.

The cheap ones on ebay cost more for shipping than for the item, and take several weeks for delivery.

I refuse to buy anything from China, if there is an alternative, so that eliminated several others.

I finally decided on Sunpentown (From Taiwan) model 1891B; $180 from naturalsolutions1.com, with free ground shipping from Chicago area. I didn't see any options to pay extra for air shipping. I want one for myself, and one for a wedding gift. The wedding is in a week and a half - hopefully it will get here in time. I ordered one - I'm going to cheat and open the wedding box to take a look before I order a second one for myself.

Let me know if you think you find a better solution!

Dick

I believe my original model did come from China......but it worked and is still in use with a friend in the UK.....

For testing and getting used to it, I would still buy the cheap one.....personally.

Yabut! Not for a wedding gift to my best friend's daughter...:)

My gift version (Sunpentown 1891B) arrived today. Fortunately, the inner box was not sealed, so the recipients won't be able to tell that I tried it out... Yep, it heats water way faster than my resistance cooktop!

In one sense, we are at a disadvantage here in the USofA, as the 120 V 15 A limits portable devices to around 1800 watts. This one says consumption 1300 W, so at close to 90% efficiency, it should put just under 1200W into the pan at max heat. Of course I could install a European 220V outlet....

I don't want to risk dirtying the unit, so I won't attempt any frying. The (tiny) operator's manual says not to put paper or cloth between the unit and the pan to avoid overheating. This indicates to me that it must sense the glass surface temperature to regulate cooking temperature.

My one big disappointment: in my research I thought I saw that this brand was made in Taiwan; the unit I received was made in China (like nearly everything else)

Thats another China.....!

The cheap ones do come from that region.....sadly.....

Before I gave the gift to its intended recipients, I couldn't resist trying it a bit more...

I made a batch of Quince Jam. Of course I didn't want to get the unit dirty, so contrary to the operator's manual and following Andy's advice, I put a sheet of newspaper on top of the unit. I boil the jam down quite a bit, and in the past it has always splattered jam all over the place (there is even a spot on the ceiling from some years past), as bubbles rose to the surface and popped. With this unit, I had such precise control of heat that I was able to do the job with virtually no splatter, much less stirring, and no sticking/burning to the bottom. After about three hours of cooking, The newspaper was not the slightest bit browned. I suspect the owner's manual says not to use it just to avoid any possibility of liability.

In any case, I will do a bit more research before getting my own unit, but I will get one!

I bought a portable one for €40 from a mail order company and my wife did the testing, to the point that she cooked almost exclusively on it......only using the ceramic hob when she had to.

She loved induction from day one and she is not a person for new fangled things really!!!

I ought to mention that I have no financial connection with Induction cooking what so ever, sadly!!!

If I was 20 years younger, I would try and get in on the ground floor!!

Please reference Wikipedia, it mentions the points I have already made and some more....one for example:-

According to CEG Electric Glass Company, "[Induction cooking] power savings of 40-70% are realistically achievable in comparison to conventional cooktops." CEG Electric Glass Company also states induction cooking has an efficiency rate of 90%, while Electric and Gas have efficiency rates of less than 50%.

Reference:-

http://en.wikipedia.org/wiki/Induction_cooking

I was once informed that France made all the running in this area for many years, before other countries slowly caught on.....one up to France!!!

As French cooking (and French cooks) are some of the most renowned, this does suggest that the rest of us have been a bit slow to catch onto a good thing.

There is a German Cordon Bleu Chef, somewhere on the web, that has only used induction in his restaurant for several years......

From 1995!!!:-

Innovative new products highlight '95 NRA Show - National Restaurant Association Restaurant

Link:-

http://findarticles.com/p/articles/mi_m3190/is_n23_v29/ai_16987051

A Japanese producer of induction ranges showed a prototype of a conveyor griddle with dual induction cooking elements that grill both sides of burgers and other meat products automatically. Several American conveyor grill manufacturers are looking at the technology.

There seems to be some serious misunderstanding

Thank you Andy

I stand corrected and admit jumping the gun. The oven I improvised on once was introduced to me as a induction hob. After reading your explanations it became clear that I was not well informed enough to make such stark comments about induction cooking. I will keep complaining about a spiral under glass contraption though, which I assumed induction cooking was.

If it works as well as you say couldn't it be used on a larger scale? I'll think about it, now that I better understand the technology. Vielen Dank. Ky.

Ky I have no problem with that, you are not the first to confuse those red rings or even the halogen versions with induction.....you will certainly not be the last!

Don't worry, be happy or at least stay happy at all times possible.....!

Induction cooking is something that until you have the opportunity to try it out yourself, you will not appreciate its full benefits. This is why, a little over 2 years ago I bought a cheap portable single unit to experiment with and learn.....it cost €40 or around $50 or so. It was a good investment that neither myself or my wife have once regretted.....

Once our new kitchen is installed either at the end of this month or the beginning of the next, we will ONLY have induction cooking in this house.....the ceramic hob that we have at this time (the ones that glow red under glass after a few seconds), will be gone forever. Not that it has got used much over the last couple of years anway!

Did you see the possible percentage of electricity savings with induction cooking that a US company posted on Wikipedia, even higher than I anticipated.

I can also say that even if there was NO savings in electricity at all, I would still recommend Induction for all of its other fantastic qualities.....

Have a great day Ky.

Thanks again Andy

I had a good look at the industrial applications of induction heating. Very interesting to say the least. Yesterday I wanted to out law it (I still suffer a bit) and today I would buy shares. When mis-understandings go full circle education is the result. I'll have one in my workshop just to experiment. I can think of a few ways to use it other than heating food. See what happens. Have a great day. Ky.

That is fantasticle, I can hardly believe it. The sceptic makes me ask; do you know how it could possibly control the temperature of the pan? How can it sense this with any accuracy?

I have read that some saucepans for induction cooking have a ferro-magnetic (or something) layer on the INSIDE of the pan that heats the food direct. So, what ever temperature sensing method would have to see through the base of the pan to have any idea of the temp inside, or it would just sense the outside temperature of the pan which i guess is likely what it does.

Do you have any more clues about the temperature sense and control side of induction cooking? I think if the guys who make and sell these things would do much better if they unveiled some of the mystery about how they work!

Thanks!

I have also thought about it, I have no idea, but publishing details of the temperature sensing would also tell the opposition.......

May I suggest that you buy a test single Hob as I did (I am sure that the US has them, but I do not know where you are based, sorry!) and check that you have a couple of pots that a magnet sticks on the base (the magic test for functionality!) and try it.

That is all I did and it convinced me hands down.....

A test hob cost me €40,- from a mail order company a few years ago, the American ebay sells them today for $32 or so (no bids) it would seem, a cheap investment!!!!

You can buy them on ebay for example in the following countries, all dirt cheap!

Germany:-http://cgi.ebay.de/SupportPlus-PORTABLE-INDUCTION-HOB-STOVE-COOKER

UK:-

http://cgi.ebay.co.uk/electric-induction-hob-great-for-camping-new-in-box_W0QQitemZ220158464129QQihZ012QQcategoryZ71247QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

USA:-

http://cgi.ebay.com/NR-Portable-induction-cooktop-cooker-rang-stove-burner_W0QQitemZ330175758928QQihZ014QQcategoryZ71248QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I Hope this helps you.....

I recently tried something new on our Induction hob - we have an old, cheap Wok that burns the food where it has contact, is really not hot enough everywhere else as the bottom is simply not flat enough, when used on a normal electric hob. On gas it is OK, but using it for the first time on induction was fantastic, totally even heating and wonderful control.

I am just amused at myself that I have never tried it out before.....we live and learn!!!

Hi Andy!

Thanks for the update...

I've been very disappointed that I've never heard anything, good or bad, from the couple I gave an induction cooker to last October for their wedding. I suspect that they've never tried it...

I did try it before I gave it to them, and was thrilled... One of these days I'll get my own!

Dick

Maybe you can get it back and give them something else......? But they are really missing out!!!

A cousin of mine who does some top French cooking for his girlfriend is totally happy now since I swapped him one for two empty German gas cylinders he did not want!!! (He lives in the UK!)

And do not forget, they are cheaper than a house fire......and look much much better!!!

If you do get one of these, you may find that your wives will really like it (if they do the cooking), mine did and she hates ANYTHING different or new usually.........I had a fight to install CFLs and LED lighting in many places in the house!!!! She has got used to that as well over the last 10 years in all......

Interesting thread, I was clueless as to the existence of induction cooktops (hob was new to me too). I have been seeing induction teapots proliferate lately; they heat the water faster than anything else I have seen and the pot comes off the base, leaving the base plugged into the wall: no cords come with you. I just bought one yesterday, haven't even used it yet.

From an EE standpoint, monitoring temperature would not be difficult, but it would be somewhat inaccurate compared to what I would do in an industrial application. What I would do is to monitor the power going to the "load" (the cooking vessel in this case) through the induction coil and knowing whether the ferrous metal had a positive or negative temperature coefficient of resistance (I don't know that now, but probably positive), I could indirectly know that as the power through the induction coils changed up or down (as the case may be), the vessel was at a known temperature delta. Then by simply measuring ambient, I could calculate the vessel temperature. Boil that down to a DSP and voila! Closed loop food temperature control! Like I said, it wouldn't be terribly accurate, but how accurate is your temperature sensor on a gas or resistance cooktop now? I use my finger, probably would continue to do so. But in doing this in a closed loop manner like that, I would have good control of the cooking heat, so that may be the answer to the OPs question.

Side note:
Doing some light reading on the subject, they are 84% efficient in terms of heat energy transfer to the food, whereas resistance heating (coils) is around 73% radiant / halogen is 74% and gas is around 40% (best efficiency models, cheap gas models can be as low as 18%!). That said, Gas still comes out to be cheaper, at least here in the US, because it starts out much cheaper than electricity in terms of cost per BTU. I switched to gas a few years ago, but not because of energy costs (only 2 of us in the house, we don't use much anyway). I switched because I like the responsiveness of gas. From everything I have read so far, it appears as though induction cooking is as good, if not better!

I may give this a try on my next remodel.

Two points that you brought up that I might be able to clarify a little better:-

1) Naturally it depends on the power of the induction hob you are using, (variable between 1200 and 3000w, depending upon manufacturer), ours are 1400 and 1800 on the doubles and 2300 on the single hob, mainly because of them being portable and the maximum ampere for a socket in Europe is 16 amp in the UK 13 amp, but I have never see water boiled so fast neither has my wife!!

2) With regard to temperature control, I was boiling potatoes yesterday on an 1800 watt ring, I set 100°C and 25 minutes time. The potatoes were boiling steadily with the lid on, I removed the lid and with a conventional hob, the potatoes would go off the boil, but with the induction, the boiling "rate" carried on exactly as before for several minutes. I then replaced the lid and you could see that for a few seconds, the boiling stopped as there was enough heat already in the pot......I found it almost unbelievable.....

If you want to question me further, please do.

Sure, no worries. I didn't mean to raise your heckles, I just do not understand your statement:

"I then replaced the lid and you could see that for a few seconds, the boiling stopped as there was enough heat already in the pot......I found it almost unbelievable....."

What function of physics or induction caused this phenomenon?

I, like half the folk in this thread, have aspirations of becoming aquainted with induction technologies.

I thought that I had explained it at the time, but for you I will endeavour to explain it again!

On a normal hob, if you set the hob to the lowest temperature that still boils the water in a pot with the lid on and get it stable (let it settle for a few minutes or so), removing the lid stops boiling, why? because the heat escaping is now more than that which the hob is supplying. Got it?

Now with the induction hobs that I have, removing the lid DOES NOT CHANGE THE BOILING RATE! The hob has automatically and seamlessly added the extra energy required to keep the pot at the temperature requested (how it senses this do not ask, I haven't a clue)...

Now replacing the lid, causes the boiling to stop/slow down for about 3 seconds, why you may ask, because the energy now stored as heat in the pot is now slightly more than the pot needs, eg. a slight dip in the graph. It is only just noticable....

I myself did not believe my eyes at first and I made the same test 5 or 6 times.....each time with the same results.....I find it totally unbelieveable.....I have no explanation other than the above......whether its what really happens I cannot prove either way, sorry....it was just a fun thing. I will try and find a way to prove it better....but do not hold your breath.....

Today I made (for me at least !) a useful discovery, that I should have noticed a long time ago, that makes life even easier when using Induction hobs....and is safer than conventional Hobs....

It is very simple and maybe you will think that it is unimportant, but then I suspect you do not cook very often!!! Let your wife read this through....before you laugh!!

Usual method with cooker tops (Hobs) OTHER than Induction for cooking Boiled Potatoes.(Gas, Halogen and Ceran)

1) After Potatoes have been prepared, placed in water and generally salted (most people!), placed on Hob, Hob is switched to maximum heat, lid is maybe placed on.

2) Potatoes come to the boil, reduce heat, adjust and adjust and adjust until water is boiling still, but not boiling over. Gas is easier to adjust in this respect of the conventional means.

3) Check every 5 minutes or so, or remain in kitchen for a time, clean off boiled over residue, except where it is still hot, re-adjust heat.

4) Come back in say 20 minutes, switch off, drain potatoes, serve etc...

5) Wait till hob is cool, clean off blackened boiled over residue from Hob...scrub for 10 minutes on some!!! Remember, only on the first day, before you had ever cooked on it, did this Hob appear to be clean, never since! But you have spent WEEKS cleaning it since it arrived!!

6) If you forget the Spuds, they boil dry, burn and put flakes of soot all over the kitchen, then you throw away pot, think about the electricity Bill and the time to clean the whole kitchen.....if this had been OIL, YOU WOULD NEED A NEW HOUSE!!!

New simple method with Induction Hob for cooking Boiled Potatoes.

1) Place saucepan with prepared Potatoes, in salted water on Hob with lid on.

2) Switch on, select temperature, set to 100°C, select time, set to 20 minutes plus time to boil, say 5 minutes, therefore set to 25 minutes. (This 5 minutes depends on the amount of water generally speaking and the power of the Hob in use. Experience will quickly tell after a single saucepan has been brought to boil in this manner.)

3) Leave kitchen (no more adjusting required.)

4) Return to kitchen after 25 minutes to find no boiled over residue on the Hob and potatoes are cooked. Hob has already turned itself off after giving a short BEEP to signal end of cooking. Drain and serve. Immediately wipe down Hob (just warm) with a wet sponge, no soaps or detergents, looks like it just came out of the showroom again!!!

5) So even if you forget the potatoes, nothing will happen, except that they will cook on slightly in the still hot water (serve as Mash Potatoes, nobody will notice!!), but cannot boil dry!!

Today I made another discovery. using the method I illustrated above, I cooked rice today, with a fatal flaw(s), I cooked for too long and I did not have enough water in the pot!! (Getting old! Sorry, GOT old!!)

Normal Hob.

After the water is used up, the rice would start to burn and give the whole kitchen a "charcoal effect".....smell would be terrible. We have all done it at some point.

With an induction Hob.

Only a single layer of rice went slightly brown and stuck to the bottom of the saucepan. All the rest was fine and fully edible....

Why? Because the temperature was held at 100°C and did not climb as it would on a normal Hob.....

After removing the good rice, I added water and the stuck on rice came off with no problem whatsoever....

I was watching a late night (probable repeat) of a cooking program of a very well known Chef here in Germany, AND HE WAS COOKING ON AN INDUCTION HOB, a huge one with 6 "heating positions" of various shapes. Very fancy!!

At the end, the Hob looked as clean as it had been before being used!!!!

I was looking around for some Induction Hob cooking tips on the web and I came upon the following, which explains the way induction hobs work rather well and easily understood I feel.

How induction cooking works

I'm a bit of a cook and I remember these hobs being hailled as the new wonder hob for the kitchen back in mid 80's (?) and then I hadn't heard a thing.

I've just read through this thread and I didn't know you could still buy these induction hobs, let alone the portable ones...

So thanks Andy, I will be making a test purchase soon methinks!

John.

Just a quick question Andy, is it possible to use an aluminium saucepan with a disc of ferrous metal inside at the bottom of the pan?

Just a though - John.

I have given that some thought, yes I believe it would work, BUT I can only recommend it for when you are only cooking with water or salted water, as anything else getting under the piece of metal could burn I feel......but you could do a few experiments and let us know your findings please....

Even with magnetic stainless as the insert, I'd be very concerned about electrolysis with the aluminum.

You mean regarding alu & steel together with water.....never thought about that, but I think he just wants to test how quickly it warms water up.....not to drink....

By the way, if you find a tiny magnet, take it with you when shopping for pots & pans, if the magnet sticks, it will work!!

There are some alu pans with a piece of steel sandwiched in the base, they work fine.

No, I think he is looking for a way to cook in solid aluminum pans using induction... But you might be right!

Dick

Hopefully not, I am sure that he will have read your good warning.....

It was just a passing thought...

Afterall if a ferrous disc could be used then old saucepans could be of continued use...

Obviously the disc would have to be enamalled or something, but it could make for a cheap item to sell with the induction hobs?

John.

I don't want to run your idea down, but other than checking quickly how fast water boils, I do not think that you would be happy with the results, even enameled.....

I would guess that it would need to have many holes as well to let the liquid pass through easily.....even then, it might still not be really viable.....maybe you could invent something here!!!

1. I've always thought that the pitting that is always evident in aluminum pots should be taken as a warning - I only use aluminum for sterilizing jars prior to canning.

2. The enamel or whatever would restrict heat flow from the disk to the food, requiring at least a little higher temperature in the disk than that of a magnetic pan, and adding a delay between changes of setting and changes in effective cook temperature.

3. The holes Andy suggested would increase heat flow, but would reduce eddy currents and the efficiency of the disk.

Dick

Good point.....

I wonder if a really thick piece of steel, wrapped in a Stainless "Jacket" might be better....

But really the best things are induction capable pots and pans.....as someone else pointed out, they are no more expensive than any other really.....

Most people who try Induction cooking are so impressed with its good points, they end up buying new pots & pans.....its the only bad point I feel....!

You are one of the brave ones! probably 1 in 10 actually put their money where their mouth is (you and me for example!), 9 do not believe it, but everyone I know who has actually tried it is totally blown away.....

There are basically no minus points, unless you already have a lot of relatively new cookware, that is incompatible to induction.....but with a relative cost of ownership (electricity wise) around 50% of normal methods.......even that can be got round....

Try a small single unit, they go for under $50 on USA ebay for example.....I paid €40 for my first one and have never looked back!!! Still totally sold on them after over 2 years experience.

Great for camping.....

I've just been looking on ebay.co.uk Andy and they are very reasonably priced...

some are selling for only £30 others brand new are selling for £49 all of them look superb!!

As I have a small kitchen I chucked out my oven back in 93 and use 2 microwaves, one being a combination fan oven and grill...

So one of these looks ideal for the odd occasions when I need a ring for cooking, ideal also because it remains relatively cool, so it would be easy to store away after use!!

I wonder why they just haven't had the advertising or recognition they deserve? maybe because they are a littl more expensive?

John.

I'm only guessing, but they are so cheap (at least in portable format!! bu expensive in "built in" format!!), I guess a lot of people either think that they are a fad or they have bough expensive incompatible pots & pans....

Sad, they are really missing out.

We now have 2 x double hobs and 1 x single hob, all portable and in our new kitchen, there will be no built in hob at all, we just bring out what we need and use it, before putting it away. So depending upon the number of pans required, we can go from 0 to 5!! If that turns out to be a restriction, I will buy another one!!!!!

We were extremely lucky that the then new pots were all compatible to induction, not planned, just luck!!

My wife is an even bigger fan than I am.....and she does not like "New fangled things" generally speaking!!! I was surprised how she took to it instantly.....

Well Andy, at last my induction hob has turned up this morning, I bought it on ebay for £30 brand new!!

Its fantastic!!! boils water faster than my kettle (I timed it!) As you said you can set temperature to 120*C and watch it boil set 100*C and watch it simmer set 80*C and its off the boil.... turn it up and within seconds its boilling!!!

Fantastic!!! you've another convert here now!

John.

I am not sure that i wanted to "convert" anyone......sounds awful, but I am very happy that you are happy....did you have your Rosary in your hand when switching on for the first time?

You are another one who "Puts his money where his mouth is!", my compliments to you....!

So many people slag new things and they themselves have completely no idea......

The cheap units are definitely the way to go when you start off to see if they do what you hope they do. The expensive one can follow later.....!

If you are married, what does your better half say, that is really important indeed!

Keep us updated too....

Minor but important update that I half knew about but did not take seriously till I saw a test on German TV a few minutes ago.

In the test they "forgot" 2 liters of good cooking oil on a gas stove, on an electrical resistive stove and an induction stove.

Only two caught fire, because before the oil went "critical" on the induction stove, the stove switched itself off with over temperature!!!!!! you have to wait ten minutes till it resets before you can cook further.....

The Induction tops have a thermostat in them and are supposed to shut off between 200 and 220°C , gas and normal electric do not as a general rule!!

Thanks Andy

There are a number of us here on CR4 who are approaching or in their 'Golden years' (whatever that means). As the years pass, our 'forgetters' become more and more active, so this is an important point. It is so easy to go do something while the stove is heating up, get distracted by something else we see on the way to the original something, and come back to find the blackened pan on the stove that we entirely forgot about!

Dick (Still consider myself approaching...)

My wife "forgot" when she was about 35, luckily I went back to the house after she had casually mentioned that she had left stuff cooking!!! and it was only a black pot!!!! She is not very safety minded, thats my job!!! It does cause arguments from time to time....

But it could be a "Black" kitchen or even a complete house!!!!!

Happy Christmas to you....

My wife was still quite young (35 or so) when she "forgot" a frying pan!!! (previously mentioned!) Luckily although it caught fire and the pan was ruined, the small amount of fat did not destroy the decorations.....since that time she is NOT allowed to fry in deep fat. I also have smoke alarms in the kitchen and where a TV is (most rooms!) and hallways and stairs.....

A friend of a friend told me that her rings heated up when she was frying something. Not much, but it is something to think about. Most haus fraus have wedding rings, and plenty of male cooks have wedding rings or watches.

Oh yeah...the workings in her digital watch were destroyed by a casual pass through the induction field. The surface is not hot, so she rested her hand (with the watch at her wrist) on one of the "hobs". Again...anecdotal evidence. I will need to do some experiments....perhaps there was something else involved.

Anybody with one of these induction cook tops have any experience with rings and watches?

I don't wear rings or watches, but I just placed both a copper and a steel ring (didn't have gold or silver handy) right next to the base of a pan with a little less than a cm of water, and boiled the water, on our induction cooktop.

When the water was boiling, I felt both rings. The copper ring was unaffected; the side of the steel ring closest to the pan and element was slightly warm, while the side away from the pan was unaffected.

My wife does wear rings, and sometimes a watch; she has never complained. We have a dual cooktop with 2 induction elements and 2 radiant elements. Now that she has gotten used to the induction, she rarely uses the radiant ones. Until recently there was one small aluminum pan she used to cook one or two eggs, and of course could not use the induction side. She found a similar pan in cast iron (and made in the USA, which to us is a big plus), and since she found that I've never seen her use the radiant elements. I would notice if she did, because I commonly clean the kitchen, and the radiant side of the cooktop is MUCH harder to clean!

All the induction cooktops/hobs I've used (2 portables and one built-in) will not operate unless there is a relatively large magnetic pan or similar object placed on the element. Lifting the pan half a cm off the surface will cause it shut down and display an error indication. I was able to get it to heat a magnetic spatula (about 8 x 11 cm), but none of the silverware placed there did anything (and this was magnetic stainless silverware).

Obviously the unit must emit some field to sense the presence or absence of the pan, so it is conceivable that it could have some effect on a watch, but everyone I know that wears a wristwatch, wears it with the watch on the outside of the wrist. The magnetic fields decay very rapidly with distance from the element (I've checked that using an oscilloscope), so I seriously doubt whether the induction unit damaged the watch.

This is especially true , as I have checked the operation of digital watches and calculators in the presence of strong permanent magnet fields, and the ones I tried were unaffected.

Thats good stuff! Thank you! She had told me that she had place her hand right on hob. Its what I suspected. A confirmation bias at work.

I can't imagine a gold ring heating up just from the inductance...there would not be ANY hysteresis to speak of. Certainly much less than copper. Of course induced current flow in a gold ring would exist, but I didn't think it would make much difference.

And you have proven that!

Keuuuuul!!!!

You bet! Great link!

I did find a silver ring that is marked "850". I believe that means it is 85% silver, and I suspect that most of the rest is copper. I repeated the experiment with fresh cold water and the silver ring barely touching the outside of the pot. By the time the water boiled, I could barely detect that the ring had warmed sliiightly. That amount of warming could easily be attributable to radiation and convection from the pot.

I think you are right...

I just came across a cheap calculator that I was willing to sacrifice, so I tried using it while boiling the water. It did indeed fail while right next to the pot and less than 1 cm above the induction element, but as soon as it was moved away slightly, it resumed working normally, and has continued to do so. I tried this several times, with identical results.

There is not a great difference in technology from a digital calculator to a digital watch, so although I obviously can't guarantee that her specific watch would be unharmed, I suspect that something else caused the problem with the watch.

Minor update.

Hi, some months ago I bought another new Induction Hob (stove top), one with a glass top surface this time. It works out that its not as good as the original ones I bought with the high temperature plastic hob.

Why? Might you ask.

Well the temperature sensor is under the glass and the pot is on top, so it takes several minutes for the sensor to "see" the temperature achieved by the pot and it tends to "overdrive" the top until the temperature equalizes itself....

Its still usable, but you have to readjust the power several times...