What are the little black specs in a can of saurkraut?

The little black specs in a can of sauerkraut are typically bits of spices, such as pepper or caraway seeds, or they may be small pieces of burnt cabbage. They can also be remnants of the fermentation process, which may include yeast or other microorganisms. Generally, these specks are harmless and do not affect the safety or taste of the sauerkraut. If there is any concern about the product, it's best to check the packaging or consult the manufacturer.