The enzymes involved are proteinases ( cathepsins вЂ“ B, D, H & L, and calpains) and exopeptidases ( peptidase and aminopeptidase). The dry curing of ham involves a number of enzymatic reactions. Under certain conditions, especially during cooking, nitrites in meat can react with degradation products of amino acids, forming nitrosamines, which are known carcinogens. Because of the toxicity of nitrite (the lethal dose of nitrite for humans is about 22В mg per kg body weight), some areas specify a maximum allowable content of nitrite in the final product. The amount and mixture of salt and nitrites used have an effect on the shrinkage of the meat. Nitrates are used because they prevent bacterial growth and, in a reaction with the meat's myoglobin, give the product a desirable dark red color. Most modern dry cure hams also use nitrites (either sodium nitrite or potassium nitrate), which are added along with the salt. Some dry cured hams, such as the Jinhua ham, take approximately 8 to 10 months to complete. The duration of the curing process varies by the type of ham, with, for example, Serrano ham curing in 9вЂ“12 months, Parma hams taking more than 12 months, and Iberian ham taking up to 2 years to reach the desired flavour characteristics. It is then hung to air for another period of time. The hams are then washed and hung in a dark, temperature-regulated place until dry. Specific herbs and spices may be used to add flavour during this step. This process involves cleaning the raw meat, covering it in salt while it is gradually pressed draining all the blood.

Traditional dry cure hams may use only salt as the curative agent, such as with San Daniele or Parma hams, although this is comparatively rare. Sea salt being added to raw pork leg as part of a dry cure process Additionally, smoking may be employed, and seasonings may be added. Ham is produced by curing raw pork by salting, also known as dry curing, or brining, also known as wet curing. Д«ecause of the preservation process, ham is a compound foodstuff or ingredient, being made up of the original meat, as well as the remnants of the preserving agent(s), such as salt, but it is still recognised as a food in its own right. It began to refer to the cut of pork derived from the hind leg of a pig around the 15th century. The modern word 'ham' is derived from the Old English ham or hom meaning the hollow or bend of the knee, from a Germanic base where it meant 'crooked'. It was certainly well established by the Roman period, as evidenced by an import trade from Gaul mentioned by Marcus Terentius Varro in his writings. Larousse Gastronomique claims an origin from Gaul. There are claims that the Chinese were the first people to mention the production of cured ham. The preserving of pork leg as ham has a long history, with Cato the Elder writing about the 'salting of hams' in his De Agri Cultura tome around 160 BC.

The long dark cured gut