Using a meat thermometer is the most reliable way to know when your pork loin is done, because there aren’t any trustworthy visual indicators of doneness as there are for chicken and beef. A bit of pinkness doesn’t necessarily mean it’s undercooked—in fact, it could be perfect at that point! Hazel says that as long as it’s cooked to an internal temperature of 145 degrees F, it will be safe to eat. And frankly, it’s so hard to tell if it’s ready otherwise, I wouldn’t recommend cooking pork unless you have a meat thermometer. Luckily, they tend to be pretty affordable, and if you don’t already have one, you can buy one for less than $11 here.
Using a brine or a marinade will make your life so much easier.
If you’re not confident in your cooking skills, there is one foolproof way to guarantee your pork ends up on the tender side, even if you cook it too long: Soak it in a brine or a marinade. According to Hazel, these kinds of preparations always produce the most tender outcomes. She gets the best results when she brines her pork for two to six hours in a simple solution made of 1 cup kosher salt and 2 quarts water, though you can also add herbs, peppercorns, sugar, bay leaves, and other seasonings or spices as you like. Just be sure to rinse off the brine before you start cooking, otherwise it will be too salty.
A marinade is a bit different from a brine because it relies on ingredients like vinegar and citrus to tenderize the meat and add flavor, but the two techniques produce a similarly tender final product. In fact, marinades are really what revolutionized the way I cook pork loins, because they’ll still be tender even if you cook them a bit too long, so you have a room for error. And you don’t have to rinse off a marinade the same way you would a brine, so they’re a bit less work, too.
And you can make a marinade out of whatever you have in your pantry! For this story, I marinated a couple pork loins in a simple mixture of soy and fish sauce, rice vinegar, and chili flakes in the fridge overnight. To be honest, I accidentally overcooked them by a minute or two, but they were still tender and juicy thanks to my marinade.