"Pastured" is a term more commonly used to refer to poultry and their eggs, but it's important to understand what pastured pork is (and isn't). In the culinary world "pastured" doesn't have a legal meaning or certification process, so this information includes the common practices (and not any legalities) surrounding pastured pork.
Pastured Pork: How It's Raised
Pastured pork comes from pigs that live how pigs might live if left to their own devices: in fields and woods, free to move around.
They have small shelters where they can sleep in small groups. Sows usually give birth in these shelters and feed their piglets in, or near, the shelter.
Pastured pigs receive feed from a farmer in addition to the food they root for themselves. This feed may or may not be certified organic, so the pork that results from these pigs may or may not be certified organic. Since they aren't crowded together in unhealthy conditions, pastured pigs do not commonly receive unnecessary antibiotics.
Where to Buy Pastured Pork
Pastured animals tend to be raised on small farms. The farmers often sell their goods at farmers' markets and other direct-to-consumer methods. Many farms that sell pastured meat are often proud of how they care for their animals and will happily share the details with potential customers. Beyond a marketing tactic, these farmers have embraced the work it requires to pasture pigs because it results in a better tasting product.
Some farms raising pigs this way will even offer farm visits. Beware, pigs are smart, social animals. Spending too much time with them may make you rethink whether or not you want to be eating them!
Why Bother With Pastured Pork?
People turn to pastured or grass-fed meats for a wide range of reasons.
First, the meat often has deeper, richer, or more complex flavor than factory-farmed meat does. Second, for many people, knowing that the animals they eat were raised humanely is important, as is the lessened use of antibiotics. Third, pastured and grass-fed animals tend to have a more positive impact on the environment. Finally, many shoppers want to support local farmers and the local economy. Buying pastured pork (or other local goods) does that.
Connection Between Pastured Pork and Heritage Hog Breeds
Quite a bit goes into raising pastured pork. It requires more work than just letting pigs run free in a field. Some industrialized pork farms have bred out many behaviors pigs need to survive in natural conditions, including caring for their young (sows without the right instincts will roll over on and kill their own piglets or can even trample them underfoot).
To counteract these bred-out behaviors, a lot of pastured pork comes from heritage or heirloom hog breeds, which retain instincts that allow them to live healthfully in a more natural environment. By breeding these types of pigs, farmers ensure that they remain a part of the farm landscape and make them available to consumers at local markets.