Hams, as sold in the United States, are offered for sale following a variety of preparations, from cooked to dry-cured. However, the hams most widely available are ready to eat immediately after defrosting. Also known as city hams, these hams have been brined so that a seasoned saltwater solution penetrates deep into the meat, adding flavor and keeping the meat juicy. They are then smoked and sold whole, fully cooked. Despite this, heating your ham to the correct temperature is important for food safety.
City hams are sometimes sold vacuum-packed and refrigerated. These hams do not need defrosting. However, larger hams are often frozen because they will keep longer. Defrost frozen hams in the refrigerator in their commercial packaging. A slow thaw is necessary to reduce the chance of bacteria forming as the ham warms. A small ham will defrost at roughly 4 to 5 hours per pound, while larger hams need 5 to 7 hours per pound. To thaw faster, dunk your frozen ham in a sink filled with cold water, completely covering the ham. Keep the ham in its original packaging. Replace the water every 30 minutes. Small hams will defrost in 2 to 3 hours, while larger hams require 30 minutes per pound.
While precooked hams can be eaten at room temperature, immediately after thawing, they are often heated and glazed for a more elegant presentation. To serve warm, preheat your oven to 350 degrees Fahrenheit, and remove the ham from its original packaging. Place the ham in a roasting tray, brushing with a sweet glaze if you like. Tent your ham with foil to trap in moisture, and cook in the oven for roughly 10 minutes per pound. City ham is ready to eat when the internal temperature reads 140 F for commercially made hams, or 165 F for home-cooked city hams.
As they are such large cuts of meat, there is often leftover ham, which can be saved to use in sandwiches, salads or soups. The leftover meat can also be reheated to be served as slices for a ham dinner the next night. Storing whole, uncut pieces of ham means they will last longer in the fridge or freezer without spoiling or losing flavor, as there is less exposed meat.
Store extra ham wrapped in plastic wrap or tinfoil in the fridge for 3 to 5 days. Well wrapped, the extra ham can be frozen in slices or as a large piece for 1 to 2 months. To use frozen leftover ham, thaw in the refrigerator for 24 to 48 hours or longer, depending on the size of the piece. Like with whole hams, leftover ham can also be defrosted in a water bath.
References and ResourcesSerious Eats: The Food Lab's Definitive Guide to Buying and Cooking Hams
What's Cooking America: How to Cook and Prepare Perfect Ham -- Ham 101
Dakin Farm: Spiral Sliced Ham Serving Suggestions
Honey Baked: Spiral Sliced Ham
U.S. Department of Agriculture: Safe Minimum Internal Temperature Chart
FoodSafety.gov: Ham Storage Chart