It is more common during the really cold months of January and February for this to happen. It could be that the potatoes are being stored too cold at the distribution warehouse. I have actually heard potatoes cracking once pulled out of a cold warehouse and onto an unrefrigerated dock, same thing at a terminal market. Cracking is caused when potatoes not able to adjust from going from very cold temperatures to warm temperatures quickly. Looks like little thumbnail cracks.

We usually don’t see much of this in Idaho storage, just sometimes in the winter. I’d look at the steps along the way to see if they are being stored in too chilly a setting. I tell distributors to move the potatoes from the higher parts of the warehouse and from the back to the front. Less air circulation occurs up high and almost always near the back it’s colder. Ideally they are to be stored towards the plastic curtains the Hysters are using, this moves the air around and is warmer from the area being open more often.

Q&A: Timing from Harvest to Grocery Store Shelf

University of Idaho College of Agricultural and Life Sciences: Thumbnail Cracks of Potato Tubers