Resist the temptation to defrost pork tenderloin on the counter overnight. Harmful, illness-inducing bacteria grow rapidly at temperatures above 40 degrees Fahrenheit, and some can double within a 20-minute window of time. To preserve flavor and keep your family and yourself safe, always follow safe food handling guidelines and only thaw frozen meat using a safe method. Options range from thawing that tenderloin in the refrigerator to cooking it while it's still frozen.
Defrost Pork Tenderloin in the Fridge
According to the USDA's Food Safety and Inspection Service, the optimal method for defrosting pork is to place the frozen meat in the refrigerator with its wrapping intact. To avoid leakage, or having condensation create a mess in the fridge, place the meat in a bowl or food safe container to catch any liquids. The pork should go on the bottom shelf of your fridge, to minimize the risk of dripping on other foods.
Small roasts can take up to 3 to 7 hours per pound. Thawing time is directly affected by the temperature of the refrigerator — the colder the fridge, the longer the meat takes to thaw. If you're thawing just one tenderloin it will go rather quickly. If you have frozen two or three together in a solid mass, treat think of them as a single pork roast of their cumulative weight. Your total thawing time may be 24 hours or more.
Defrost Pork Tenderloin in the Microwave
When you're short on time and need to thaw the pork out quickly, thawing it in the microwave can be a good option — it typically only takes 5 to 10 minutes. However, this method should only be used when the meat will be cooked immediately in order to avoid potential bacterial growth.
Use the defrost setting on your microwave, or check the manual to determine the proper setting to use while thawing meat. Check the pork every few minutes. Take it out of the microwave and get cooking as soon as it's defrosted. The thin, tapering ends of a pork tenderloin are prone to overheating and cooking through before the thicker areas are thawed, so fold them underneath once they've begun to thaw. This creates a more even thickness, and helps prevent them from cooking.
Defrost Pork Tenderloin in Cold Water
Another speedy thawing method is to place the frozen pork tenderloin in leak-proof packaging and submerge it in a sink filled with cold water. Drain and refill the water every 30 minutes while the pork thaws. The size of the pork tenderloin affects how long it takes to defrost. Less than 1 pound of pork generally takes less than 1 hour, while a 4-pound package containing multiple tenderloins might take 2 to 3 hours to thaw using this method.
Avoid using hot water, which can speed up the thawing time — but it also begins cooking the exterior of the meat while also encouraging the growth of potentially harmful bacteria that can cause foodborne illness.
Cooking Pork Tenderloin From Frozen
Everyone has been there at some point — you forgot to take the meat out in time and are in a hurry. The good news is that you can start cooking, even if the pork tenderloin is still frozen. Just tack an additional 50 percent onto your cooking time. For example, if you are cooking a tenderloin that typically takes 1 hour in the oven when it's cooked from a thawed state, add an extra 30 minutes to the cooking time to calculate how long a frozen tenderloin needs.
Checking Pork Tenderloin for Doneness
Whether you're cooking perfectly thawed pork tenderloin, or meat that's still frozen, there's only one reliable way to be sure the meat is fully cooked. Insert an instant-read thermometer in the meatiest part. Once the thermometer reads 145 degrees Fahrenheit, the pork has been cooked fully.