In Animal Farm, how does Napoleon control the food supply?

Napoleon sets up a system of rations to control the dwindling food supply. He also designs the food troughs to appear full and abundant, yet in reality, he is filling them with sand and topping it off with meal. Napoleon wants to give the impression that food is plentiful.

Napoleon also uses the food supply to control the other animals. By withholding rations, he maintains power.When the chickens refuse to allow their eggs to be sold, Napoleon cuts off their rations, and declares any that provide them with food will be put to death.