Ham is a cut of meat from the thigh of the hind leg of an animal, especially pigs. Nearly all hams sold today are fully cooked or cured.
Ham is uncooked preserved pork. It is cured (a preservation process)
usually in large quantities of salt and sugar. Then the ham is hot smoked (hung
over a hot, smokey fire but out of direct heat) to preserve it more.
This process keeps the pink hue of the uncooked meat. Standard pork,
like chops, are raw and unpreserved. When heat is applied to the meat a
chemical reaction happens that turns the hemoglobin white. This also
happens when an acid is applied to meats.
The pink color of ham develops in the curing process which involves
salt and usually either nitrites or nitrates. The nitrate cure is used
for product that will either be kept a long time or at room temperature
like dry salami. Most hams are cured with nitrite and salt today.
The cure prevents the growth of unhealthy or deadly bacteria
before enough moisture is withdrawn by the salt. This is particularly
important if the product is to be smoked above 40F when these bacteria
grow. The "danger zone" for uncured product is between 40F and 140F.
There is confusion in the words curing and brining. Brining is done
with salt and usually sugar and only alters the product color a little.
Curing is done with salt and nitrates.
Sodium nitrite is used for the curing of meat because it prevents bacterial growth and, in a reaction with the meat's myoglobin,
gives the product a desirable dark red color. Because of the toxicity
of nitrite (the lethal dose of nitrite for humans is about 22 mg per kg
body weight), the maximum allowed nitrite concentration in meat products
is 200 ppm. Under certain conditions, especially during cooking, nitrites in meat can react with degradation products of amino acids, forming nitrosamines, which are known carcinogens.