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Wednesday, November 18, 2009

How to Cook Your Veggies

You know that you have to eat your vegetables, even though you may not like to. Did you know that how you cook vegetables affects how they look? Here's a simple experiment that you can do!

What You'll Need:
3 small, micowave-safe bowls
Measuring cup
Measuring spoons
Vinegar
Baking soda
Water
Microwave oven
Oven mitt
Spoon
Frozen green vegetable, such as peas

Pour 1/4 cup of water into each bowl. Add 1 tablespoon of vinegar to one bowl, and add 1 teaspoon of baking soda to another one. The third bowl should only have water in it. Add about 1/8 cup frozen vegetable pieces to each bowl (about 20 peas, if that's what you're using). Cook all three bowls in the microwave using high power for about 5 minutes. It doesn't matter whether you do them one at a time or all at once. When they're done, carefully remove the bowls from the microwave with the oven mitt. They will be very hot!!! Compare the vegetables - look at their color and mash them with a spoon to check their texture. What do you see?

You'll immediately notice that the vegetables cooked in vinegar (an acid) look grayish and very yucky. Who would want to eat them? The veggies cooked with baking soda (a base) look nice and green, but they are disgustingly mushy when you mash them with a spoon. Why do they turn out so different?

The green color is due to a molecule called chlorophyll, which has a magnesium (Mg) atom in the middle. Cooking in acid removes the magnesium and puts two hydrogens (H) in its place. The H-containing version of chlorophyll is a dull, ugly green color, and that's what you see. Cooking in a base doesn't remove the Mg, but it does break down the walls of the plant cells that keep the vegetable nice and firm. Without those strong walls, you can easily smoosh the cells together using a spoon. Vegetables cooked in water only keep a pretty good green color, and don't get mushy. Which one would you like to eat??

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