The two types of ribs come from different places on the pig. This seemingly small detail makes all of the difference in the flavor and texture of the ribs.
Spare ribs (pictured, top: meat side, rib side) are the Flintstones of ribs—bigger, tougher and meatier in every way, compared to baby backs. The ribs are cut from the belly of the pig—where bacon comes from. Because they’re so meaty, it takes longer to cook the ribs to the point that the tough and fatty meat breaks down to fall-apart tender. In most supermarkets, spare ribs are trimmed St. Louis-style, with the rib “tips” removed (pictured). This trim makes the racks more attractive, and can helps the ribs cook more evenly. Occasionally, you might run across whole, untrimmed racks of spare ribs. They’re generally a better value because they have more meat, including the tips.
Baby back ribs (pictured bottom: rib side, meat side) are cut from the loin section—the place where pork chops come from. If you think about what a bone-in pork chop looks like, a baby back rib is a pork chop with most of the meat (the “loin”) removed. In grocery stores, baby backs may also be labeled “loin back ribs” or “back ribs.” Baby backs are smaller, less fatty, and naturally more tender than spare ribs, which also means they take less time to cook. They’re the most popular rib, partly because they’re neat, compact and easy to eat—practically dainty compared to spare ribs.
How to cook ribs:
Gas grills seem to be the tool of choice on The Nest. If you have a reliable grill thermometer (or even an oven thermometer set on the grate), you can make fine ribs using the 3-2-1 method:
3 hours, bone-side down on the grill at a steady 225 degrees.
2 hours, wrapped tightly in foil, bone-side up on the grill at 225 degrees.
1 hour, unwrapped and bone-side down on the grill at 225 degrees.
To keep the temperature in the grill steady, put a disposable aluminum loaf pan filled with water inside the grill. Place the water pan over the burner set on “high”, and lay the ribs on the side of the grill with low (or no) direct heat.
If you're into low and slow charcoal smoking, my friend and Barbecue Life Coach, Gary Wiviott, has a great step-by-step program for cooking on a Weber Smoky Mountain. (Full disclosure: We're working on a book together, and I've learned absolutely everything I know about barbecue from this guy.)
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