Whether you're just learning to cook or want to take your meals to the next level, one of the really confusing things about the culinary world is how many foods are similar to each other. Consider pork, for example. Some recipes will tell you to buy a pork roast that weighs so many pounds, and leave it at that. More often, they'll call for a specific roast, like a Boston butt. The difference, in a nutshell, is that every Boston butt is a pork roast, but not every pork roast is a Boston butt.
Choose a Roast From Anywhere
One of the reasons pork is so versatile is that you can pick a roast from almost anywhere on the animal. The tenderest are pork roasts cut from the loin, with or without the ribs attached, but the sirloin, hind leg and shoulder all make fine roasts, as well. Even the fatty belly meat, usually used for bacon, can be slow-roasted for an especially rich dish. The problem is that most of the hog can be used for more profitable purposes. The belly usually becomes bacon, the hind leg becomes ham and the tender loin cuts often go for pork chops. That means roasts cut from those areas tend to be a bit pricey. If you're a frugal shopper, the shoulder is your best bet for an economical pork roast. That's where the Boston butt comes in.
Cut It Down
A whole pork shoulder is a seriously large cut. Unless you're feeding the entire neighborhood, it's probably too much pork for one meal, so it's usually divided into two smaller pieces. The lower part of the shoulder becomes a picnic roast, a narrower cut like the shank end of a ham. Some pork shoulders are cured as picnic "hams," though true ham comes from the hind leg. The upper part of the shoulder becomes the Boston butt, the equivalent of a chuck or blade roast in the beef world. They'll weigh up to 9 pounds with the bone in or up to 7 pounds when they're boneless, so retailers will often cut them down into smaller pieces that work better for everyday meals. Boneless or bone-in, full-size or smaller, it's a really versatile cut.
Compare and Contrast
A Boston butt roast has a lot in common with chuck roasts, the comparable cut of beef. They're both flavorful cuts, they both have plenty of marbling and connective tissue, and they're made up of lots of smaller muscles running in different directions. The difference is that a pork shoulder isn't nearly as tough as a beef shoulder. A chuck roast is really only useful when it's slow-cooked or braised until it's falling-apart tender. Boston butt works great that way, too – that's how pulled pork is made – but you can also cook it as a conventional roast, and serve it sliced for dinner or in sandwiches.