I can not say what they are exactly but sure are linked to an intestinal fungal growth. Candida cells are microscopic, even the elongated cells. I have been said they are dead tissue as a result an active yeast growth that mixes with mucus, etc. I don't know if candida can form visible biofilms or colonies of that magnitude. If you ask me my opinion, they are fungal colonies protected by a matrix. This is only my opinion and can be far from the true.
Some people have experimented with some of these balls and reported fermentation after keeping them in water with White Sugar .
So far, I don't know the absolute true about them.