Hosting a holiday dinner or a Sunday family gathering often centers around a centerpiece protein, and few things are as crowd-pleasing as a succulent, glazed ham. Because most hams purchased at the grocery store are already fully cooked or hickory-smoked, the task isn’t actually “cooking” the meat in the traditional sense. Instead, your goal is to reheat the ham so that it stays juicy, reaches a safe internal temperature, and develops a beautiful exterior without drying out. Understanding exactly how long to heat a cooked ham is the difference between a tender masterpiece and a salty, leathery disappointment.
Understanding Your Ham Type
Before you set your oven timer, you must identify what kind of ham you have. The heating time and method vary significantly based on the cut and how it was processed.
Fully Cooked vs. Partially Cooked
Most hams found in the refrigerated meat aisle are labeled “fully cooked.” These have been cured and smoked or boiled, meaning they are technically safe to eat cold right out of the package. Reheating is done purely for flavor and texture. However, some hams are labeled “cook before eating” or “ready to cook.” These require a longer time in the oven and must reach a higher internal temperature to be safe for consumption. Always check the packaging first to ensure you are following the correct safety guidelines.
Spiral Cut vs. Whole or Half Hams
Spiral-cut hams are incredibly popular because they are pre-sliced all the way to the bone, making serving a breeze. However, because the meat is already sliced, it is much more prone to drying out during the reheating process. Whole or half hams that are not sliced have a protective layer of fat and skin that helps retain moisture, allowing them to withstand slightly longer heating times or higher temperatures.
General Time and Temperature Guidelines
The golden rule for reheating a fully cooked ham is to go low and slow. While it might be tempting to crank up the heat to get dinner on the table faster, high heat will evaporate the moisture within the muscle fibers before the center of the ham even gets warm.
The Standard Oven Method
For a standard oven, you should set your temperature to 325 degrees Fahrenheit. This temperature is high enough to warm the meat thoroughly but low enough to prevent the edges from burning.
As a general rule of thumb, you should plan for 10 to 15 minutes of heating time per pound of ham. For example, if you have a 10-pound ham, you are looking at a total time of approximately 1 hour and 40 minutes to 2 hours and 30 minutes.
Target Internal Temperatures
Even though the ham is already cooked, the USDA recommends specific internal temperatures for quality and safety. For a ham that was packaged in a federally inspected plant, you want to reach an internal temperature of 140 degrees Fahrenheit. If you are reheating a “leftover” ham or one that was not packaged in a controlled facility, it is safer to aim for 165 degrees Fahrenheit.
Step by Step Process for Reheating
To achieve the best results, you shouldn’t just toss the ham in a pan and hope for the best. A few extra steps in preparation will ensure the meat stays moist and flavorful.
Preparation and Moisture Retention
Remove the ham from its packaging and discard the plastic disc often found on the bone end. Place the ham in a roasting pan. To prevent the meat from drying out, add about a half-cup of water, apple juice, or white wine to the bottom of the pan. This creates a steamy environment that keeps the meat hydrated.
The most important step is wrapping the ham. Use heavy-duty aluminum foil to cover the ham tightly. If the ham is very large, you may need to use two pieces of foil and crimp them together. The goal is to trap the steam inside so the ham “sweats” rather than roasts.
The Mid-Point Check
About 30 minutes before your estimated finish time, use a meat thermometer to check the internal temperature. Insert the probe into the thickest part of the meat, making sure not to touch the bone, as the bone conducts heat differently and will give you an inaccurate reading. If you plan on applying a glaze, this is the time to do it.
Mastering the Glaze
A glaze adds that iconic sweet and savory crust that everyone loves. However, glazes are usually high in sugar, which means they burn very easily.
When to Apply Glaze
Never put your glaze on at the beginning of the heating process. If you do, the sugar will caramelize and then char long before the ham is warm. Wait until the ham reaches an internal temperature of about 130 degrees Fahrenheit. Remove the ham from the oven, increase the oven temperature to 400 degrees Fahrenheit, and brush the glaze generously over the surface.
The Final Blast of Heat
Return the uncovered ham to the oven for the last 15 to 20 minutes. Keep a close eye on it. You want the glaze to bubble and turn a deep golden brown. Once the internal temperature hits 140 degrees Fahrenheit, remove it from the oven immediately.
Alternative Heating Methods
While the oven is the traditional choice, other appliances can be used depending on the size of your ham and your kitchen setup.
Using a Slow Cooker
If you have a smaller ham (usually 8 pounds or less), a slow cooker is a fantastic way to keep the meat moist. Place the ham in the crock, add a splash of liquid, and cook on the “Low” setting. In a slow cooker, you should plan for about 20 to 30 minutes per pound. This is a “set it and forget it” method that frees up your oven for side dishes.
The Countertop Roaster Oven
For very large hams during holiday seasons, a countertop roaster oven works just like a conventional oven. Follow the same 325 degrees Fahrenheit temperature setting and the 10 to 15 minutes per pound rule. These roasters are excellent at retaining moisture because of their smaller, enclosed space.
Resting the Ham
One of the most overlooked steps in heating a cooked ham is the resting period. Once the ham comes out of the oven, transfer it to a carving board and tent it loosely with foil. Let it rest for at least 15 to 20 minutes. This allows the juices to redistribute throughout the meat. If you cut into it immediately, all that precious moisture will run out onto the board, leaving you with dry slices.
Common Mistakes to Avoid
Even seasoned cooks can run into trouble with ham. Here are a few things to watch out for:
- Heating at too high a temperature: Anything over 350 degrees Fahrenheit for the duration of the heating process will almost certainly dry out the exterior.
- Forgetting the water: Without a small amount of liquid in the pan, the bottom of the ham can become tough and salty.
- Not using a thermometer: Guessing the time based on weight is a good start, but every oven is different. A thermometer is the only way to guarantee perfection.
- Overcooking: Since the ham is already cooked, every minute it spends in the oven past the target temperature is simply removing moisture.
FAQs
How long does it take to heat a 5lb cooked ham?
At 325 degrees Fahrenheit, a 5-pound ham will take approximately 50 to 75 minutes to reach the desired internal temperature of 140 degrees Fahrenheit. It is always best to start checking the temperature at the 45-minute mark to ensure it doesn’t overcook.
Can I reheat a spiral ham without it drying out?
Yes, the trick to a moist spiral ham is to wrap it very tightly in foil and add liquid to the bottom of the pan. Because the slices are exposed, they lose moisture faster than a whole ham. You can also place the ham cut-side down in the roasting pan to protect the slices from direct heat.
Is it safe to eat a “fully cooked” ham without reheating it?
Yes, hams labeled “fully cooked” can be eaten cold or at room temperature. Many people enjoy cold ham in sandwiches or as part of a charcuterie board. Reheating is primarily for the purpose of serving a warm meal and enhancing the flavor with a glaze.
How long should I heat a precooked ham in a slow cooker?
In a slow cooker on the Low setting, you should heat a precooked ham for about 4 to 6 hours total, or roughly 20 to 30 minutes per pound. Ensure there is some liquid at the bottom, such as apple cider or water, to maintain a moist environment.
What should I do if my ham is still frozen?
It is highly recommended to thaw your ham completely in the refrigerator before heating. This can take 24 to 48 hours depending on the size. If you must heat a frozen ham, you will need to increase the heating time by approximately 50 percent, and you must keep it covered with foil for the entire duration to prevent the outside from burning while the inside remains icy.