If the colony has no Food MULEs installed and there is neither Food in the store nor any of the players' storage, the game immediately ends with the message: "The Colony failed due to a complete lack of Food!"
So ... Lets say you've got food up to really high prices on turn 11. On turn 12, everyone stops producing food.
At the end of turn 12, there is one food in the player supply, none in the store, no food mules, and the price falls to nothing (need = 0, supply = 1).
But in that same game, if I had not had a spare food left over, would we have ended turn 12, with zero food needed, but no food mules and no food in storage for a colony death?