Last weekend I made butternut squash soup. In an experiment to get more of the squash browned I peeled two medium squash and cut them into 2 inch chunks, rather than just halving it, before roasting in the oven. (Result of the experiment was OK, but the extra exposed area also allows more moisture to escape, so I wouldn't recommend this method.)
Halfway through peeling the 2nd squash I noticed that the fingers on my left hand (I'm right-handed) were getting yellow and that the skin was drying, cracking, and tightening up. The yellow I can understand as transfer since I was using that hand to hold the squash while peeling. But I've peeled butternut plenty of times for various recipes and this hasn't happened before. Washing my hands didn't help. The problem went away after a couple of days.
Does anyone want to venture an explanation? Did my fingers O.D. on carotene or potassium?
Best Answer
It's definitely a very real reaction. I'm not sure exactly what in the squash it is that causes it, but since different people react differently - some people have strong reactions like you, some people have mild ones, and some have no problem at all - it seems to be some sort of mild allergic reaction. It's often called contact dermatitis, but that's a very generic term and doesn't really mean anything you don't already know. I'm not sure exactly what component of the squash it is that causes it, but I don't think it's carotene or potassium. It's likely some more complex molecule that tends to be present in various winter squashes.
Images from http://foodworld-eva.blogspot.com/2010/01/squash-reaction-on-skin.html.
You can avoid it by completely wearing gloves while working with the squash, or if you're lucky, you have someone else with you who can handle the squash without problems. For many purposes, like soup, you can also simply cut the squash in half, roast it, then scoop out the good stuff. But if you do really need to peel it and cut into chunks, your best hope is just to try to avoid touching it too much. You'll also want to wash your hands immediately after, or even a few times while you're cutting if it takes a while.
If you do end up with this despite your best efforts, cortisone cream can help relieve the reaction afterward.
(And as for your soup, there's nothing wrong with letting more moisture escape in exchange for browning. You can always just add more water or stock back into the soup. This can even be a good thing, since it lets you replace water with a more flavorful liquid.)