Pigs do not require pasture and are versatile as they will eat any scraps (similar digestive system to humans) and/or forage.
If preserved (smoked, pickled etc), the meat and organs from a large pig can last a group of people a long time.
https://www.youtube.com/watch?v=Z5AcsBIeDAs
Similar to dogs, pigs have a keen sense of smell, they can even be trained to find truffles, which can be sold as a premium sought-after foodstuff.
https://www.youtube.com/watch?v=qSq0t1YBrDE