Browning of Apples

We’ve all observed apples browning, and if you saw Chrysalis Cate’s first apple oxidation experiment you know that this browning is caused by oxygen in the air interacting with the apple and “oxidizing” it. One way to slow the reaction is to put an acid, such as lemon juice, on the apple slices. My new question: Can we remove the oxygen from the air to stop the apples from browning?

In the process of brainstorming I was reminded of two other experiments we’ve done. In our first candle trick we mixed baking soda and vinegar to create carbon dioxide, and then the carbon dioxide was used to extinguish a candle. Our second candle trickinvolved a candle in a closed container, and the fire used up all the oxygen in the container, then went out.

Since oxidation and burning both require oxygen, I predict that the same things that extinguished the candles in our other experiments can be used to remove the oxygen from around apples, and then keep them from browning.

Here’s what I did to test this prediction – but watch out! You might want to change it before trying it yourself. I got three largish containers of the same size and prepared apple slices in three small cups that can fit inside. In the first container, I put the apple cup inside along with a burning candle, then covered the container with aluminum foil sealed as tightly as I could get it. (Remember that, with a candle, you’ll need adult supervision.) In the second container, I poured some vinegar into the container, then added baking soda and waited for it to bubble before adding the apple inside. (Be careful – if the apple isn’t balanced well in the cup, it will tip into the vinegar.) I then covered this container tightly with aluminum foil, too. I wanted to make the containers as similar as possible, so that the only differences between the containers were the variables I really cared about. The third container was my “control” – I didn’t do anything special to it. I just put the apple cup in the...