The Food Lab: Better Home Cooking Through Science

For some time, I’d thought that it’s better to season your
potatoes when they are hot, but I’d never actually figured
out why. Do they actually absorb more seasoning, or could
it just be a psychosomatic effect? To find out, I cooked three
separate batches of potatoes, this time using green food
coloring as a stand-in for the salt and vinegar. The first
batch I cooked in green-colored water. The second batch I
cooked in plain water, then “seasoned” with green-colored
water after draining them, while they were still hot. I
allowed the last batch to cool completely before tossing with
green water. After all the batches cooled completely, I cut a
cube from each one in half to see how far the food coloring
had penetrated.
The potato that was cooked in seasoned water and the one
that was “seasoned” while still hot were a light shade of
green all the way to their centers, while the potato that was
seasoned after cooling was mostly pale in the center, with a
single green streak where a natural fault in the potato