My son had a school project on cabbages. So I bought all the different varieties I could find to be photographed, and we asked everyone in sight for recipes, and an elderly neighbour let him photograph his gardening tools.
So far so good. But it’s nice to have something nobody else has got in their project, isn’t it?
Well, I was looking through “How to Fossilise Your Hamster” for teaching ideas, and I found an experiment involving red cabbage.
First, boil chopped red cabbage for at least 10 minutes and save the water (you can also eat the cabbage). The water will be purple, of course.
Then fry an egg. When the white just starts to lose its transparency, drip some purple cabbage-water over it. The egg white turns green.
Huh?
Well, the chemical that gives red cabbage its colour is very sensitive to acidity. Tap water is pretty much neutral, so the water from boiling the cabbage is purple. Egg whites are alkaline, so it turns green – but you can still eat the egg, and it tastes quite normal.
You saved the rest of the cabbage water didn’t you? Right, share it out between four glasses.
- Add nothing to the first one.
- Add baking powder to the second. This is slightly alkaline, so it should turn lavender.
- Add lemon juice or white vinegar to the third, and it will turn red.
- Add laundry detergent to the fourth, and it will go lurid green, and then evil yellow. Don’t even think about drinking this one.
Who’d a think it?