When I was first learning the art of barbecue, I came across many recipes calling for St. Louis ribs. This was before YouTube was flooded with videos on the topic, so, being a complete novice, I searched for them all over New York City (in my naiveté, I didn't think to just ask my butcher). I went from one place to another, finding nothing but spareribs, until I finally tracked them down at Whole Foods—let's just say they weren't cheap.
That was the one and only time I bought spare ribs pre-cut in a St. Louis-style. I figured if I learned how to trim them myself, I could save a lot of time and money, and still have more control over the final product. It turns out that trimming a rack of ribs St. Louis-style was an exceedingly simple task—just two cuts and done—and to this day, I always do it myself before seasoning and smoking.
What is a St. Louis Cut?
So maybe I should explain what St. Louis ribs are and why they're worth all this trouble: Pork ribs are divided into two main sections: the spareribs and loin-back ribs. The loin-back ribs, often called baby-back ribs, are the portion of the ribcage closest to the spine (where the loin runs); spareribs are the portion of the ribcage closest to the sternum. (Basically, if these cuts came from a human, spareribs would be the front half of your rib cage, and the loin-back ribs would be the back half of your rib cage. But we're not cannibals, now, are we?) Spareribs tend to be less curved than the loin-back ribs, and they usually have part of the breastbone/sternum attached.
The problem with a whole rack of spareribs is that the breastbone section has lots of tough pieces of cartilage in it, which end up as hard-to-chew bits (there actually is a good use for them, which I'll explain below.)
The St. Louis cut is trimmed of this cartilage-laden portion, as well as some excess flap-meat at the end of the rack. The end result is a rack of ribs that is more uniform in shape, smaller, and easier to eat—and that's why I find it so much more desirable than standard spareribs.
How to Cut a St. Louis Rack
So hopefully I've convinced you it's worth trimming your spareribs, but if not, maybe once you see how easy it is, you'll be converted. As I mentioned, it just takes two simple cuts.
The first of the two is removing the flap of meat at the end of the rack. To do this, look at the narrower end of the rack and locate the last, shortest bone. There's usually a portion of meat attached to that bone that's loose and will end up overcooking if not trimmed off. So to remove that, make a vertical cut parallel to, and about 1/2-inch away from, that last bone.
The next step is making a horizontal cut to severe the breastbone and cartilage. To find the sweet spot for this cut, first locate the longest rib, usually the fourth bone in on the wider end of the rack. Feel along that rib until you detect a softer spot: That's a cartilaginous section where the rib connects to the sternum (breastbone). All the other ribs connect to the breastbone in the same way. Make the cut by inserting the knife into the soft spot, then slicing perpendicular to the ribs, cutting through all of the soft spots where each rib meets the breastbone. Once the breastbone is removed, you should have a clean, rectangular rack of ribs with nothing but bone and meat, perfect for easy eating.
Technically the St. Louis racks are now ready, but there are a few more steps I always like to take before moving on to seasoning and cooking them.
First, I like to flip the ribs over and remove the piece of skirt meat that runs diagonally on the backside, if it's there. Sometimes the butcher has already removed it, but most of the racks I buy still have a bit of it attached, so I make sure to cut it off. If not removed, it can dry out and char while the ribs cook.
Second, I remove the shiny, thin membrane that covers most of the backside of the ribs. There's debate in the barbecue world about whether this is even worth doing: Some people say the membrane inhibits smoke penetration, but I don't buy that explanation—I've had perfectly smoky ribs that have had the membrane still attached. For me, the advantage of removing it comes down to creating a better eating experience. Once cooked, the membrane can become papery, and while totally edible, I don't find that texture pleasing.
Peeling it off is actually the hardest part of this entire trimming job—it can be slippery, making it hard to get a hold of, and even with lots of practice, there are still some racks that have membranes that just don't want to come off. But I think it's worth the trouble. To start it off, use a knife or fingernail to pry up a corner of the thin membrane from one edge of the ribs. Grab that with a paper towel—for grip—and slowly pull it upwards. Once a good portion of the membrane is free, you should be able to to pull the rest off in one quick motion.
After that, I'll feel around the ribs to see if there are any excessive pockets of fat, especially hard fat, and trim those down. Fat is good in barbecue, but when there's too much it won't render enough during cooking and you'll end up with overly fatty ribs, which are not a good thing.
As for the scraps of meat I trimmed, I try not to throw them away. I tend to freeze the flap meat for sausage-making. Even more worth saving, though, is the breastbone portion: It's the part that rib tips come from, which is Chicago barbecue's claim to fame. I like to season and smoke this piece along with my St. Louis-cut ribs. The tips are done sooner than the full rack, so I take them off the grill sooner and have them as a cook's treat while I wait another couple hours for the ribs to finish. Sure, they're a bit of a pain to eat, but those fatty tips are also damn delicious.
From start to finish, the entire trimming process only takes a few minutes, and after a rub and 5 to 6 hours in the smoker, you're left with nothing but serious eats.
Need some ideas on what do with your now beautifully trimmed ribs? Here are a slew of tried-and-true rib recipes* from over the years:
- Barbecue Rib Rub
- Kansas-City-style Ribs
- Competition-style Ribs
- Cajun Spiced Ribs
- Balsamic-glazed Ribs
- Hoisin Ribs
- Coffee-rubbed Ribs
- Dr. Pepper Ribs
*Some of these recipes are for loin (baby) back ribs, but you can sub St. Louis ribs in all of them and just increase the cooking time by about 1 to 2 hours.