Why microwaving kale, carrots, or other vegies can create sparks

Kale Chip

We’re going into the holiday season, so it’s nice to have a collection of healthy, quick snacks and appetizers to go along with the more traditional ones. And kale chips definitely fit the bill. However, making kale chips in the oven can be tricky as they either never dry out or can burn – in any event, they take an especially take a long time. So one popular solution is to use the microwave, as demonstrated in this America’s Test Kitchen Feed blog,  How to Make Kale Chips in the Microwave. We noted, however, that in comments posted on this blog, people complained about sparking. So we investigated further.

It turns out that dense vegetables such as green beans, carrots, kale, and green peppers have a higher amount of minerals  than other food items, including iron, magnesium and selenium. According to the Canadian Food Inspection Agency, cooking these vegetables in a microwave can actually create sparks; the minerals act like tiny pieces of metal and create arcing effects in a microwave. “The sparks result as the microwaves reflect or bounce off the metal. The arcing does not harm the food but it does prevent it from heating thoroughly.” So if you’d like to try this method of cooking kale, we suggest you keep a close eye on the food while you’re cooking and stop the cooking if the arcing becomes serious – too much can damage the oven.

And since we’re on the subject of videos, remember that the EYB library’s collection of videos continues to grow. You can see if a recipe has a video by noting the little video icon shaped like a little television set. Also, you can purposefully search for videos in the recipe section of the library by just clicking on the video box in the “Only Show” right-hand column. To see an example, here’s a collection of chicken recipes that have videos attached as well as kale recipes. Happy viewing!

Photo from America’s Test Kitchen The Feed

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  • gunung  on  November 8, 2013

    I wonder if those kale chips would work in a food dehydrator?

  • djw  on  November 19, 2014

    I have twice had this happen with a frozen Tilapia Fish fillet. I use a microwave dish, place unwrapped frozen fillet inside. place loose plastic lid on top to hold in a little steam an it started snap. crackle, pop! Only the thicker fillets about 1/2" -3/4" thick did this. the small ones ere fine.

  • lisaayresmith  on  April 28, 2019

    This happened to me today with 🍓 rhubarb compote on top of a whole grain cake. I was so confused 'cause I was sure there weren't any little foil bits in there! Thank you for the post. I would have been scratching my head for a while! 🤔🤨🧐

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