What makes a microwave 'spark'?

[MamaMolly]

Today I was reheating some hotdog left overs in the microwave. I placed them in a corelle (white glass) bowl and zapped them for 20 seconds. I immediately heard a funny sizzle and when I looked the hotdogs were sparking flames! Of course I turned off the microwave and didn't give them to DD.

My question is: is there anything you know of, other than metal, that can cause this? I've seen it happen once with metal, and I'm terrified that there is metal in the hotdogs. But before I go into full-tilt panic mode I thought I'd ask here.

(FWIW I did save the hotdogs just in case. It was the first one from a new package. I didn't notice it sparking the first time I cooked it, but that time it was whole and wrapped in a paper towel. I think I may have used a metal knife to cut the hotdog after it was cooked the first time. Sometimes I use a plastic one, sometimes a metal one. And I had a truly rotten day yesterday so it totally could have sparked the first time I cooked it and I just didn't notice it. I'm really hoping not, though!)

Thoughts?

[trales]

Ted Allen did a special on the food network with microwaves (the food detectives, I think). He put all kinds of things that were not metal and sparked. DH (a physicist turned lawyer) and myself (a chemist) looked at each other in shock. It was pretty cool, they did the reasons, which I cannot remember right now. I will try and research later.

[trales]

I knew I could find an answer. From the USDA.

Arcing (pronounced "AR-king") is sparks inside the microwave oven caused when microwaves react to gold paint on dishes, twist ties and other metallic materials. Some foods such as raw carrots and hot dogs can cause arcing while being microwaved. In hot dogs, this can be due to the uneven mixing of salts and additives. In carrots, it can be due to the minerals in the soil in which they were grown. Whatever the cause, turn off the oven immediately to end the sparks. Prolonged arcing can damage the oven and/or the utensil. If caught at once, arcing should not damage the oven. Remove the offending utensil or food from the oven and either substitute a microwave-safe utensil or cook the food by other methods.

[jerigirl]

Yep- carrots and hotdogs. They spark which results in little singed spots on the food. I usually try to cook those on the stove. the arcs make me nervous.

[MamaMolly]

:signthankspin: You guys are so smart! Thank you, thank you, thank you!!! I wish we had the old rating system....what a relief!

[urquie]

green beans and apples too...

http://www.windsorpeak.com/vbulletin/showthread.php?t=229732&highlight=green+beans

[Emmas Mom]

green beans and apples too...

http://www.windsorpeak.com/vbulletin/showthread.php?t=229732&highlight=green+beans

This is funny....I was just coming to post that Kidney Beans spark too & I clicked on your link. Yep....I posted about Kidney Beans on that thread too! Almost THREE years ago! lol They're still sparking in our house. Weird stuff! :bouncy:

[s7714]

I rarely see hot dogs do it, but carrots do it all the time in mine. I've also had mac & cheese do it when it was being reheated!

[pastrygirl]

Mine started zapping and sparking when I microwaved butter on a plate. It turns out I needed a part replaced! It was the part underneath the turntable, which is metallic. For some reason it had worn through.

It only happened with butter, though. That was the weird part!

[srhs]

I was babysitting as a preteen and had bacon do this in the microwave! The paper towel over the plate then caught fire! I threw water on it. (It wasn't a grease fire; it was the paper.) The little girl was so scared; I felt terrible!