As for the food - Jams and jellies and other preserved foods are a solid route to go. Also, using herbs and other plants to make teas, wines, cordials, and other beverages is a good way to get certain vitamins and anti-oxidants, and they can usually get stockpiled with a good shelf-life before they become too potent.

I also think most people should have their own chickens. I don't understand why more people don't. They are easy to replace, they don't really need to be fed often if they are free-range, they build relationships with other farm animals for safety, like cows, cats, dogs, and pigs. Basically a free supply of eggs, and if you don't like to eat eggs, you probably know someone who does. In a SHTF situation, a chicken or a dozen eggs could easily be traded for other useful items. I also like ducks for the same reasons, but you need a lake or pond to really do ducks proper.