Chou doufu is usually soaked in milk and meat early-on. The mass-produced stuff uses an already-fermented sauce that has those ingredients.
I'm sure there are sometimes vegan vendors that specifically source an alternative kind. You can buy the mass produced stuff that is specifically marked vegan if you look for it and I'm sure a vegan vendor either uses that or makes their own.
Though just to check, are the ones you're thinking of specifically vegan rather than a different kind of veggie-focused diet? If you ask a restaurant for items with no meat and no eggs it's pretty easy to get a dish with fish or a meat broth or (egg-containing) mayonnaise, folks are often unfamiliar with the "no animal products" strictness, and not just in China. It's very easy to be told that a food is vegan or vegetarian even though it isn't.
Chou doufu is usually soaked in milk and meat early-on. The mass-produced stuff uses an already-fermented sauce that has those ingredients.
I'm sure there are sometimes vegan vendors that specifically source an alternative kind. You can buy the mass produced stuff that is specifically marked vegan if you look for it and I'm sure a vegan vendor either uses that or makes their own.
Though just to check, are the ones you're thinking of specifically vegan rather than a different kind of veggie-focused diet? If you ask a restaurant for items with no meat and no eggs it's pretty easy to get a dish with fish or a meat broth or (egg-containing) mayonnaise, folks are often unfamiliar with the "no animal products" strictness, and not just in China. It's very easy to be told that a food is vegan or vegetarian even though it isn't.