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Q & A: Hot Tomatoes !!!

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Q:
In soup, why do tomatoes retain heat longer than other vegetables?
- Chuck Osborne
West Chicago, IL
A:
Chuck -

Tomatoes, like potatoes, carrots and all the other good stuff in your soup contains a lot of water. That water holds a lot of heat.

So why is the tomato sometimes hotter than the rest of the broth (which is also mostly water)? Well, the water in the soup broth is moving around a lot, and when it passes close to the air or touches the bowl, it loses heat. but the water in the tomato is mostly trapped - it doesn't swirl around with the rest of the broth when you scoop up a spoonful. So the water in the tomato doesn't come close to the air or the bowl as much and doesn't cool down as quickly.

Further, when you eat the soup, you probably drink the broth by small spoonfulls - even smaller spoonfuls if the soup is really hot. But unless you feel like eating your soup with a knife and fork, the tomatoes probably come in pretty big chunks. So you get a big bite of hot stuff instead of just a little sip.

So why do the tomatoes sometimes seem hotter than the other good stuff - like the potatoes? We've gone around quite a bit on this one, and we're really not sure, but here's a possibility:

Tomatoes hold a lot of water, but unlike potatoes, they're also really squishy, and the water is held in large-ish pockets. When you bite into a tomato, a whole lot of that hot water comes squishing onto your tongue all in one big gush. With a potato, it takes a little longer, since you have to chew it up.

-Tamara

(republished on 07/27/06)

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