I keep my food in crooks and clay vessels in my cellar, the grain stored in vessels is good for about 5-6 years, and the prepared food stored ( and sealed with piece of fat or beeswax ) on the shelf, is good for about 2 years, take off 3-4 months on some though. My cellar is 3x4x3. Decay rate for vessels: Vegetable: 0.19x, Grain: 0.13x, Other: 0.26x. For the shelves, it's 0.26x.
So I tend to just prepares meals with meat in it just before the winter and fill my shelves with it. I survive the winter easily with enough food, even got left over sealed meals for the spring. Still good for about 1.5 years.