Flavorful Fruits.

When fruits ripen, they produce a gas called ethylene (ETH-il-een). It helps make bananas soft and yellow, apples sweet and juicy, and tomatoes red and tasty. Can ethylene gas produced by one fruit help another fruit ripen? Let's see.

All you need are two quart-size self-sealing plastic bags, two large green tomatoes, and one apple.

What to do:

1. Put a green tomato in one plastic bag and seal it.

2. Put the other green tomato and the apple in the second bag and seal it.

3. Place the bags in a warm, light place, such as a windowsill.

4. Check the bags every day.

Which tomato turned red first?

The tomato in the bag with the apple!

What happened:

The apple's ethylene gas added to the tomato's ethylene gas. The extra ethylene helped the tomato ripen quickly. The other tomato did not receive extra ethylene gas so it ripened slowly.

Now try this!

Get three bananas: one green, one partly green and yellow, and one all yellow. Taste each banana. Which one tastes the sweetest? The yellow banana, because it's the ripest. As fruits ripen, their sugar content increases.

Farmers often pick tomatoes when they are green, then spray them with ethylene to make them ripen.