The canine cafeteria holds Doc's experimental sawdust dog food.
The experimental sawdust dog food was an experimental dog food composed of sawdust, invented by Dr. Emmett Brown.
The concoction was created after the failure of his experimental sawdust pancake batter. Doc's experimental sawdust dog food had much more positive results, as dogs didn't mind the taste of sawdust in their food.
The dog food was used in Doc's canine cafeteria, a dog feeding system that would open a hatch full of dog food, at a specified time set on the built-in timer.
In 1991, this invention was showcased, along with Doc's other early inventions, in a video displayed at the Institute of Future Technology.