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Trimmed vs Untrimmed Spare Ribs: Why The Distinction Matters

You can smoke spare ribs untrimmed, but it makes for a more impressive presentation if you take the time to trim the rack. To help you understand why, we’ve put together this guide that explores the difference between trimmed vs untrimmed spare ribs.

Trimmed vs Untrimmed Spare Ribs

Trimmed spare ribs—known as St. Louis-style ribs—have a uniform rectangular shape that allows them to cook and brown up evenly. There will be more meat on the rack if you leave it untrimmed, but the skirt and tips might burn before the ribs themselves have reached their optimum temperature.

About Spare Ribs

Unlike loin back ribs, which come from the upper spinal section of the hog, spare ribs are cut from the lower segment of the rib cage. The meat is rich and flavorful, with plenty of fat to provide it with an extra hit of juiciness.

In fact, the meat from the hog’s belly is typically used to make bacon. That should tell you all you need to know about the fat and flavor content of spare ribs, as they come from the same general area.

A full, untrimmed rack of spare ribs includes a long flap of meat called the skirt. This is one of the first parts you’ll remove when trimming the rack for the smoker.

Also attached to the rib bones is a section of cartilage, connective tissue, and smaller bones (sometimes called “knuckles” in barbecue parlance). These are the rib tips, which can be removed and smoked separately.

When you trim the skirt and the tips off a rack of spare ribs, they become St. Louis-style ribs. It’s not always easy to find St. Louis-style ribs at the supermarket, but you can buy spare ribs and do the work yourself.

Trimmed vs Untrimmed Spare Ribs: Which Are Better?

In our opinion, you can’t go wrong either way. There are benefits and drawbacks to both spare ribs and St. Louis-style ribs. We’ve prepared them both ways and enjoyed them on their own merits every time.

In case you still need help deciding which preparation technique to use, we’ll break down the pros and cons of each method.

Trimmed Spare Ribs (St. Louis-style)

A properly trimmed rack of ribs has more eye appeal than one that still has the skirt and tips attached. That’s one reason why St. Louis-style ribs are so popular in competitive circles.

What’s more, the uniform shape helps to promote even browning. As a result, the ribs will look even better once they come off the grill.

This benefit extends further than mere aesthetics. The ribs will cook more evenly as well, giving the meat that ideal tender texture all the way through. When left in place, the skirt and tips will usually overcook before the ribs have reached the target temp.

Remember that even if you trim the rack, you can prepare the trimmings separately. The rib tips and skirt will cook more quickly than the ribs themselves, but they make excellent snacks in the meantime.

Spare rib trimmings can also be used to make sausage or other ground pork products. There should be enough fat on the meat to turn out sausages that are nice and juicy.

The main drawback to trimmed spare ribs is the time you’ll lose preparing the rack for the smoker. Of course, if this is a major concern, you can ask your butcher to do it for you.

Untrimmed Spare Ribs

There’s no harm in seasoning and smoking the spare ribs without trimming the rack beforehand. In addition to saving time, this will result in meatier ribs.

Rib tips are exceptionally tasty. Many pitmasters are aware of this, and believe that anyone who would remove this segment is missing out on one of the key pleasures of good barbecue.

A lot of popular barbecue joints opt to leave their spare rib racks intact. This doesn’t seem to harm their results, much less their reputations. Of course, in these cases, they might be trying to save on their labor dollar.

Should You Remove the Membrane from Spare Ribs?

Whether you trim the spare ribs or leave the skirt and rib tips in place, you should always remove the membrane. This is the opaque whitish layer that runs along the bone side of the rib rack.

The membrane, or the peritoneum, is technically edible, but it has a tough texture that can affect the finished ribs. You can remove it after the ribs are cooked, but we prefer to do so beforehand.

The main reason for this is that the membrane will act as a barrier between the seasoning rub and the meat. It may also prevent the smoke from fully permeating the ribs, so by leaving the membrane intact, you could be losing a great deal in terms of flavor.

When you pull up on one end of the membrane and slide your fingers underneath, the layer should peel away easily. Use paper towels if that makes the membrane easier to grasp. You can also insert a butter knife between the membrane and the bones to aid in the task.

Don’t worry if the membrane tears while you’re trying to remove it. Just be sure to clear away all the remaining pieces before you add the seasoning rub.

How To Trim Spare Ribs

To begin, turn the rib rack over so that the bone side is facing up. You should be able to locate the skirt, which is a flap of meat that sits toward the middle of the rack.

Insert a narrow knife between the skirt and the bones, laying the blade flat. Carefully wedge the blade beneath the flap of meat, cutting until it’s been severed from the rack. Trim away any excess fat from the bone side, then flip the rack over.

The rib tips are located along the edge of the rack. Because bones don’t bend, you should be able to find the separation point by attempting to fold the rack like a book. Once you’ve located the divide, cut along the length of the rack until the rib tips come away.

Your next step is to remove the membrane. We’ve provided tips on how to do this in the section above.

Once the skirt, tips, and membrane are gone, trim away any pockets of excess fat or cartilage. You can either use your knife or scrape them away with a metal spoon. Be sure to trim both sides of the rack.

If you notice any spare flaps of meat hanging off the edges, feel free to remove those as well. These will burn too quickly to be of much use, so it’s easier to remove them now.

At this point, you should have a presentation-worthy rack of St. Louis-style ribs. Pat the rack dry with paper towels, then season and smoke according to your favorite recipe.

As for the trimmings, the only part you need to discard is the membrane. The skirt and tips can be seasoned and prepared in a similar fashion to the ribs themselves. Any usable excess fat, meanwhile, can be added to homemade sausage.

Can You Cut a Rack of Spare Ribs in Half?

It’s fine to divide a rack of ribs in half—or even into smaller portions—before putting the meat on the grill. This is a good method if the cooking grate is a bit too small to accommodate the full rack.

You can also split the rack for serving purposes. Offering a half-rack or quarter-rack to each diner makes for an impressive presentation, especially at formal dinner gatherings.

Bear in mind, though, that dividing the ribs won’t make them cook more quickly. Spare ribs will still need 6 to 7 hours on the smoker if you want them to have the proper texture.

Final Thoughts

Trimming the spare ribs will allow them to cook more evenly, and you can use the trimmings to flavor your side dishes. Conversely, leaving the rack untrimmed will save you prep time, and you’ll be able to enjoy the tips right along with the ribs themselves.

Happy grilling!