The granary stores meat, cheese, apples and bread for the peasants. Farmers and bakers also take any processed food to this building. One granary can store up to 250 units of food only, but multiple granaries can be built adjacent to each other.
The populace consumes food at a fixed rate per person, which apparently increases with higher population. Rations handed out can be adjusted in order to gain popularity or conserve food (popularity is inversely proportional to consumption rate). When there is no food left or rations are set to none, a severe popularity penalty incurs.
It is also possible to allow or prohibit consumption for a particular food type. This will conserve food in the granary, however it limits the available quantity and variety of food for the peasants. As more food types are available, bonus popularity is gained depending on variety.
Due to its function, the granary is a very important building and losing it to the enemy can force unnecessary spending on the restoring food supplies. The granary is also susceptible to fire and burns very slowly, spreading sparks around the perimeter steadily and therefore it should be protected well.