Someone mentioned that they use Geisha tuna.

The can I bought by mistake says :white tuna, water, hydrolyzed CASEIN (a
milk protein), hydrolyzed soy protein, vegetable broth (questionable for
people on a gluten free diet), salt and pyrophosphate.

We have been using Wegman's tuna (a local food chain in NY) that has only
tuna and water. We have also used Deep Sea brand, I believe carried in the
health food stores.

                         Mary Ann Gilkey