Does adding a potato to a pot of frying doughnuts result in doughnuts that are less greasy?
We’ve never heard that trick and we’re always looking for an excuse to eat some doughnuts, so we mixed up two batches of batter for our Orange Drop Doughnuts and put 3 inches of oil in each of two Dutch ovens. We put half of a peeled potato into one pot and heated both pots over a medium flame until the oil reached the target temperature of 350 degrees. Then we fried doughnuts in each. Tasters detected no difference in greasiness in the finished doughnuts, though we did notice that by the time the oil reached the requisite 350 degrees, the potato had changed from white to golden brown. We contacted our science editor to see if he could think of a reason a potato would minimize greasiness; he couldn’t. We suspect that the originator of this idea was using the potato not to combat greasiness but rather to tell when the oil was hot enough to start frying the doughnuts.
THE BOTTOM LINE: To monitor the temperature of frying oil, we recommend using an instant-read thermometer. If you don’t have one, try a peeled potato, but don’t expect precision.