When shopping for napa cabbage, we’ve noticed that some heads have tiny black spots, about the size of ground pepper, on both the leaves and ribs.
The cause of these dots, known as “pepper spot” or “black spec,” is unknown, but low light levels, high soil pH, harvesting and storage conditions, and excessive use of fertilizers high in nitrogen and phosphorus are all possibilities. Regardless of the cause, our science editor confirmed that cabbage leaves with these spots are perfectly safe to eat. But to find out if they affect flavor or texture, we set up a blind tasting. Tasters couldn’t tell the difference between unblemished leaves and those with pepper spot. And unless we’re using whole cabbage leaves, the dots are so small that they aren’t even noticeable. From now on, we’ll go ahead and buy heads of napa cabbage with the black dots without concern.