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Pork Tenderloin Fat Up Or Down? And Related Questions

When you put a pork tenderloin on the smoker, should the fat side be facing up or down? Even if you’ve never considered this question before, it’s one that you should know the answer to before you fire up the grill. That’s where we come in.

Pork Tenderloin Fat Up Or Down?

Pork tenderloin doesn’t have a great deal of fat on it, and what little there is, we usually trim away. But if you leave it in place during the smoke, position the tenderloin so that the fat side faces up. As the fat renders, it will coat the outside of the meat, preventing it from becoming too dry.

Pork Loin vs. Pork Tenderloin: Understanding the Difference

If you’re shopping for a pork tenderloin, be aware that it’s not the same as a pork loin. While the names are similar enough to cause confusion, they’re actually different cuts.

Pork tenderloin is a long cylinder-shaped cut taken from the muscle that runs along the hog’s spine. By contrast, the loin is bigger and wider, and the meat isn’t quite as lean.

Most pork loin roasts will have a noticeable fat cap on them. The tenderloin may have a bit of fat on it as well, as we’ll discuss later. However, you’re more likely to notice the silverskin that runs along one side of the meat.

A single pork tenderloin weighs about a pound. A pork loin roast, on the other hand, weighs in at around 2 to 4 pounds. That’s another easy way to tell them apart.

It’s possible to buy bone-in pork loin roasts, but the tenderloin is always boneless. Both can be sliced into smaller portions before cooking—the pork loin into chops, and the tenderloin into medallions. For the smoker, however, it’s better to leave them whole.

As the name suggests, the meat from the tenderloin is much more tender than the pork loin, although both are considered lean cuts. We wouldn’t recommend using them interchangeably, as the tenderloin cooks faster than the loin.

Pork Tenderloin: Best Cooking Methods

According to the USDA, pork tenderloin is an extra-lean cut. Nutritionally speaking, it has a similar profile to boneless and skinless chicken breast.

Price-wise, you can expect to pay more per pound for this cut than you would for pork shoulder or Boston butt. However, since it’s also sold in smaller portions and the meat is so much leaner, you’ll get a decent bang for your buck.

You can freeze pork tenderloin whole, or cut it crosswise into medallions and freeze it that way. In either case, try to thaw and cook it off within three months. The meat is so lean that a longer stint in the freezer might dry it out.

Tenderloin is well-suited to grilling, roasting, broiling, and pan-searing. Because of its lean nature, it cooks quickly, but it’s also a decent choice for the smoker. The meat has a mild taste on its own, so it really benefits from the smoke flavor.

Removing The Silverskin

When you buy a whole pork tenderloin, it should have a long whitish membrane running along the side. This is called the silverskin, and it toughens up during cooking. That’s why it’s a good idea to remove it before you add the meat to the smoker.

The silverskin should come off fairly easily. Just insert a small, sharp knife under the wider edge, then peel off the membrane, moving along the entire length of the tenderloin.

Should You Smoke Pork Tenderloin Fat Up or Down?

There may also be a swath of ivory-colored fat attached to the tenderloin. You can opt to trim this off before removing the silverskin. If you leave it in place, though, we would suggest adding the tenderloin to the smoker with the fat side facing up.

Unlike a pork butt, which requires hours of low-and-slow cooking, the tenderloin will cook through quickly (see below). That means it’s not necessary to use the fat cap as a barrier between the heat source and the meat.

This lean and tender cut will dry out if you leave it in the smoker too long. While the rendered fat won’t penetrate the meat, it will baste the surface, providing the pork with just the right amount of moisture.

If you’d prefer to crisp up the fat during the initial stages of the smoke, you can put the tenderloin on the smoker with the fat side facing down, then flip it over after about 30 minutes. That way, you’ll get the texture you want without sacrificing moisture.

How Long Does It Take To Smoke a Pork Tenderloin?

The average pork tenderloin should take about 1 to 1.5 hours to finish cooking when the smoker is set to 225 degrees Fahrenheit. If you smoke two or more tenderloins side by side, the cooking time will be about the same.

Season the pork with the spice rub of your choice. One of the best things about the tenderloin is that it doesn’t have a strong flavor on its own, so you can experiment with different flavors every time.

Oak and maple are nice wood choices for smoked pork tenderloin. Try mixing in a bit of hickory to give it an extra savory kick. Just be careful not to overdo it, since hickory can impart a bitter taste if you use too much of it.

We like to brush a bit of barbecue sauce on the pork tenderloin during the last 10-15 minutes. That gives the sauce a chance to adhere and caramelize slightly, giving the pork a sticky-sweet quality. You can also add barbecue sauce at the table.

The pork tenderloin is done when the internal temperature reaches 145 degrees Fahrenheit (see below). Use a calibrated instant-read thermometer to ensure that you get an accurate temp. The meat will continue to cook for 5 to 10 minutes as it rests.

At What Temperature Is Pork Tenderloin Done?

In the past, recipes advised cooking pork to at least 160 degrees Fahrenheit. The authors of these recipes believed that was the only way to destroy the bacteria that would cause food-borne illnesses. Thankfully, we now know that this isn’t the case.

While it’s important to adhere to food safety guidelines, there’s no need to cook pork past 145 degrees. In fact, if you leave a lean cut like the tenderloin on the smoker for too long, the meat will be dry and tough.

Pull the tenderloin from the smoker when it hits the 145-degree marker. Let the meat rest, lightly tented with foil, for about 10 minutes. When you slice into the tenderloin, you should be rewarded with juicy, perfectly cooked slices.

Should You Smoke Pork Loin Fat Up or Down?

Unlike the tenderloin, pork loin has a visible fat cap that covers the surface of the cut. The underside might have a bit of fat showing here and there, but the top surface is coated in a shiny white layer.

Some amateur chefs make the mistake of trimming off the fat cap. Don’t do that. The pork loin needs the fat to give the meat a juicy texture and richer flavor.

We would suggest scoring the fat cap before adding the pork loin to the smoker. Use a small sharp knife to create a crisscross pattern across the entire fat layer. This adds a decorative touch and helps to drain the rendered fat as the meat cooks.

Each cut should be no deeper than 1/8 inch, and it looks best if the crosshatches are positioned about 3/4 inch to 1 inch apart. Try to ensure that each cut is roughly the same size. This doesn’t have a functional purpose, but it has aesthetic advantages.

If you want your pork loin to maintain its round shape, use butcher’s twine to bind up the roast every few inches. Again, this shouldn’t affect the cooking time or the quality of the meat—it’s done for appearance alone.

You should slather the pork loin with a thin coating of prepared yellow mustard before adding the spice rub. Otherwise, the seasonings might fall off in the smoker. You can substitute Dijon for yellow mustard if that’s all you have on hand.

Pork loin provides the perfect template for a variety of flavors. We like to use a simple blend of kosher salt, freshly ground black pepper, rosemary, sage, oregano, and thyme. However, any spice rub that complements pork will work well here.

Position the pork loin on the cooking grate with the fat side facing up. Although the loin isn’t quite as lean as the tenderloin, it will still benefit from the added moisture. If you set it with the fat side down, all that rendered fat will go to waste.

The total cooking time will vary depending on the size of your roast. Aim for a cooking time of about 30 minutes per pound. A 3-pound pork loin should be done in about 1.5 hours when smoked at 225 degrees.

You can add barbecue sauce to the finished pork loin if you’d like, or simply let the seasoning rub and the smoke flavor take center stage. Your decision should hinge on what spices you used for seasoning.

The Bottom Line

For leaner cuts that cook through quickly, it’s better to position the meat with the fat side facing up. Since the tenderloin doesn’t have a great deal of fat anyway, it’s a matter of personal preference, but this is the strategy we would suggest.

Best of luck, and happy grilling!