# Why do cut grapes catch on fire in the microwave? **URL:** \ **Category:** Factual Questions\ **Created:** [January 26, 2003, 5:13pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062 "2003-01-26T17:13:27Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![ccline](https://avatars.discourse-cdn.com/v4/letter/c/9fc348/32.png) [@ccline](https://boards.straightdope.com/u/ccline)\ **Post date:** [January 26, 2003, 5:13pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/1 "2003-01-26T17:13:27Z")
I learned that a grape cut almost in half (leave part of the skin uncut) and placed flat side down in the microwave will spark and catch fire after about ten seconds. What is it about grapes that causes this? ---
**Author:** ![CrazyCatLady](https://avatars.discourse-cdn.com/v4/letter/c/dfb087/32.png) [@CrazyCatLady](https://boards.straightdope.com/u/CrazyCatLady)\ **Post date:** [January 26, 2003, 5:42pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/2 "2003-01-26T17:42:34Z")
Really, isn’t the bigger question why you would put half a grape in the microwave? ---
**Author:** ![Hermann\_Cheruscan](https://avatars.discourse-cdn.com/v4/letter/h/b782af/32.png) [@Hermann\_Cheruscan](https://boards.straightdope.com/u/Hermann_Cheruscan)\ **Post date:** [January 26, 2003, 5:44pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/3 "2003-01-26T17:44:16Z")
Really? I’m going to have to try it out. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 26, 2003, 5:50pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/4 "2003-01-26T17:50:53Z")
The microwave energy induces large voltage differences across the grape-halves, and all the current trying to squeeze through the little bit of skin between them heats it up to the point of combustion. For more microwave fun, see [here.](http://www.eskimo.com/~billb/weird/microexp.html) These experiments can be **dangereous**! Don’t try them. Really. I mean it. I’m not kidding here. ---
**Author:** ![Tapioca\_Dextrin](https://avatars.discourse-cdn.com/v4/letter/t/3d9bf3/32.png) [@Tapioca\_Dextrin](https://boards.straightdope.com/u/Tapioca_Dextrin)\ **Post date:** [January 26, 2003, 6:52pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/5 "2003-01-26T18:52:01Z")
> [@](#): > > \*Originally posted by Q.E.D. \* > \*\* For more microwave fun, see [here.](http://www.eskimo.com/~billb/weird/microexp.html) \*\* Why post a link that installs crap on my computer without asking? ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 26, 2003, 6:53pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/6 "2003-01-26T18:53:10Z")
Didn’t install anything on mine. What did it do to you? ---
**Author:** ![Tapioca\_Dextrin](https://avatars.discourse-cdn.com/v4/letter/t/3d9bf3/32.png) [@Tapioca\_Dextrin](https://boards.straightdope.com/u/Tapioca_Dextrin)\ **Post date:** [January 26, 2003, 6:53pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/7 "2003-01-26T18:53:44Z")
It put hotbar or something ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 26, 2003, 6:59pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/8 "2003-01-26T18:59:29Z")
I don’t see how. I just looked at the page source, and there’s no javascript, server-side includes or anything else that can install anything. Wherever you got it, it wasn’t this site. ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [January 26, 2003, 7:20pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/9 "2003-01-26T19:20:53Z")
> [@](#): > > It put hotbar or something You probably picked it up elswhere. Last I checked, bbeaty wasn’t a member of the axis of evil. Here’s bbeaty’s link to a [grape-specific site](http://www.pmichaud.com/grape/). ---
**Author:** ![bibliophage](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bibliophage/32/7615_2.png) [@bibliophage](https://boards.straightdope.com/u/bibliophage)\ **Post date:** [January 26, 2003, 7:23pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/10 "2003-01-26T19:23:56Z")
> [@](#): > > \*Originally posted by Tapioca Dextrin \* > \*\*Why post a link that installs crap on my computer without asking? \*\* I really suspect it was something else. The link did nothing untoward to my computer, and I tried it with two different browsers. The site is maintained by a member in good standing, **bbeaty** , whom I have alerted to this issue via e-mail. ---
**Author:** ![Tapioca\_Dextrin](https://avatars.discourse-cdn.com/v4/letter/t/3d9bf3/32.png) [@Tapioca\_Dextrin](https://boards.straightdope.com/u/Tapioca_Dextrin)\ **Post date:** [January 26, 2003, 8:06pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/11 "2003-01-26T20:06:29Z")
Must have been me, but that’s what happened. One of life’s little mysteries. ---
**Author:** ![bbeaty](https://avatars.discourse-cdn.com/v4/letter/b/c0e974/32.png) [@bbeaty](https://boards.straightdope.com/u/bbeaty)\ **Post date:** [January 26, 2003, 10:48pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/12 "2003-01-26T22:48:23Z")
Once you were at “Unwise Microwave Experiments” did you click on some other link on that page? There’s a whole collection of links to other “microwave” websites there. If one of them is doing weird things I’d like to know about it. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 26, 2003, 10:50pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/13 "2003-01-26T22:50:16Z")
Hey, **bbeaty**. Love your site. I actually did a few of the experiments on that page. 😃 Shhhhh…don’t tell the kids 😉 ---
**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\ **Post date:** [January 26, 2003, 11:50pm UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/14 "2003-01-26T23:50:34Z")
Fun with Grapes - A Case Study [http://www.pmichaud.com/grape/](http://www.pmichaud.com/grape/) Pretty says it all. ---
**Author:** ![hobbes730](https://avatars.discourse-cdn.com/v4/letter/h/97f17d/32.png) [@hobbes730](https://boards.straightdope.com/u/hobbes730)\ **Post date:** [January 27, 2003, 2:54am UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/15 "2003-01-27T02:54:16Z")
Try putting a small foil-lined chip bag in the microwave for a few seconds. Now _that’s_ fun. I assume no responsibility for any…_unintended_ results… 😃 ---
**Author:** ![Meatros](https://avatars.discourse-cdn.com/v4/letter/m/b4bc9f/32.png) [@Meatros](https://boards.straightdope.com/u/Meatros)\ **Post date:** [January 27, 2003, 3:00am UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/16 "2003-01-27T03:00:18Z")
> [@](#): > > \*Originally posted by CrazyCatLady \* > \*\*Really, isn’t the bigger question why you would put half a grape in the microwave? \*\* You know, I used to do this trick all the time. I would wow my friend and amaze onlooker. Notice I didn’t put an “S” on the end of either of those… My “tricks” didn’t amuse 😕 ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [January 27, 2003, 3:23am UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/17 "2003-01-27T03:23:11Z")
> [@](#): > > \*Originally posted by Meatros \* > \*\*My “tricks” didn’t amuse 😕 \*\* Steel wool, or a 60 watt lightbulb would have ! Ooooh, Aaaaah, Eeek :eek: ---
**Author:** ![3.885AM](https://avatars.discourse-cdn.com/v4/letter/3/58956e/32.png) [@3.885AM](https://boards.straightdope.com/u/3.885AM)\ **Post date:** [January 27, 2003, 3:42am UTC](https://boards.straightdope.com/t/why-do-cut-grapes-catch-on-fire-in-the-microwave/151062/18 "2003-01-27T03:42:10Z")
Can you say “dipole antenna” sure you can. Next try an old cd (AOL works best) WARNING MESSY AND DANDEROUS DO NOT ATEMPT WITHOUT ADULT SUPERVISSION!