It’s funny how we do things without thinking or challenging where they came from. I remember endless hours peeling and cutting potatoes sitting hunched over a massive pot of cold water, when I was running summer camps for children.
This was always a morning job, because it took quite a long time to prepare potatoes for 50 or so people. At the same time, it was a good fun, we peeled potatoes as we chatted away and if it wasn’t for the cold fingers and occasional blisters, it would be actually quite enjoyable.
We always put the potatoes into the water, but I thought at the time that was to wash them before we cooked them!
I was so used to doing that even at home, that I never questioned why I’ve been doing this, until somebody asked me whether it helps to prevent potatoes from browning. So, for the fun of research I thought I’d look into this and find out!
Why do potatoes go brown?
Why do potatoes even go brown when you cut them up? Well, it’s apparently to do with an enzyme called polyphenol oxidase (tyrosinase) which starts to turn potatoes brown, when it’s exposed to the air (well the oxygen in the air, to be precise).
So, if we want to prevent potatoes from browning we need to prevent this enzyme to get into contact with oxygen. You can do this by keeping potatoes in water, covering it with oil or using your potatoes as quickly as possible, after you’ve peeled them.
If you have a lot of potatoes that you are trying to preserve, it might be easier to freeze them than to risk going them off or sprouting.
Preventing potatoes to go brown by using water
This is the easiest way to prevent your cut potatoes from going brown. Have a large saucepan ready with cold water and as you peel and cut your potatoes, simply drop them into the water.
When you have enough potatoes for your dish, rinse them again once or twice with cold water to get rid of any dirt and put them on your hob to boil.
Preventing potatoes to go brown by using oil
If you are preparing potatoes for roasting or frying, it’s better to use oil instead of water. If you put your potatoes into water first and then coat with oil to roast (or even fry) you might get splatter as they fry and roast.
You only need to coat your cut and pealed potatoes with oil as you go. Peel and cut few and then drizzle them with few oil drops.