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39-548: Ham is a cut of meat from an edible mammal's rear, usually from a pig. Ham or HAM may also refer to: Ham Ham is pork from a leg cut that has been preserved by wet or dry curing , with or without smoking . As a processed meat , the term ham includes both whole cuts of meat and ones that have been mechanically formed. Ham is made around the world, including a number of regional specialties. In addition, numerous ham products have specific geographical naming protection. The preserving of pork leg as ham has

78-495: A Ayurvedic remedy for digestion and diabetes in the Indian subcontinent. It is also used to make Paneer . The activity of proteases is inhibited by protease inhibitors . One example of protease inhibitors is the serpin superfamily. It includes alpha 1-antitrypsin (which protects the body from excessive effects of its own inflammatory proteases), alpha 1-antichymotrypsin (which does likewise), C1-inhibitor (which protects

117-443: A peptide bond involves making an amino acid residue that has the cysteine and threonine (proteases) or a water molecule (aspartic, glutamic and metalloproteases) nucleophilic so that it can attack the peptide carbonyl group. One way to make a nucleophile is by a catalytic triad , where a histidine residue is used to activate serine , cysteine , or threonine as a nucleophile. This is not an evolutionary grouping, however, as

156-404: A smokehouse or an atomized spray of liquid smoke such that the product appearance is equivalent; a " hickory -smoked" ham must have been smoked using only hickory. However, injecting "smoke flavor" is not legal grounds for claiming the ham was "smoked"; these are labeled "smoke flavor added". Hams can only be labeled "honey-cured" if honey was at least 50% of the sweetener used, is at least 3% of

195-593: A long history, with traces of production of cured ham among the Etruscan civilization known in the 6th and 5th century BC. Cato the Elder wrote about the "salting of hams" in his De agri cultura tome around 160 BC. There are claims that the Chinese were the first people to mention the production of cured ham. Larousse Gastronomique claims an origin from Gaul . It was certainly well established by

234-402: A multitude of physiological reactions from simple digestion of food proteins to highly regulated cascades (e.g., the blood-clotting cascade , the complement system , apoptosis pathways, and the invertebrate prophenoloxidase-activating cascade). Proteases can either break specific peptide bonds ( limited proteolysis ), depending on the amino acid sequence of a protein, or completely break down

273-548: A number of enzymatic reactions. The enzymes involved are proteinases ( cathepsins – B , D , H & L , and calpains ) and exopeptidases ( peptidase and aminopeptidase ). These enzymes cause proteolysis of muscle tissue, which creates large numbers of small peptides and free amino acids , while the adipose tissue undergoes lipolysis to create free fatty acids. Salt and phosphates act as strong inhibitors of proteolytic activity . Animal factors influencing enzymatic activity include age, weight, and breed. During

312-437: A peptide to amino acids ( unlimited proteolysis ). The activity can be a destructive change (abolishing a protein's function or digesting it to its principal components), it can be an activation of a function, or it can be a signal in a signalling pathway. Plant genomes encode hundreds of proteases, largely of unknown function. Those with known function are largely involved in developmental regulation. Plant proteases also play

351-543: A role in cell regulation and differentiation. Lipophilic ligands, attached to lipocalin proteins, have been found to possess tumor protease inhibiting properties. The natural protease inhibitors are not to be confused with the protease inhibitors used in antiretroviral therapy. Some viruses , with HIV/AIDS among them, depend on proteases in their reproductive cycle. Thus, protease inhibitors are developed as antiviral therapeutic agents. Other natural protease inhibitors are used as defense mechanisms. Common examples are

390-441: A role in regulation of photosynthesis . Proteases are used throughout an organism for various metabolic processes. Acid proteases secreted into the stomach (such as pepsin ) and serine proteases present in the duodenum ( trypsin and chymotrypsin ) enable the digestion of protein in food. Proteases present in blood serum ( thrombin , plasmin , Hageman factor , etc.) play an important role in blood-clotting, as well as lysis of

429-763: A similar manner to bacon . Peptidase In the absence of functional accelerants, proteolysis would be very slow, taking hundreds of years . Proteases can be found in all forms of life and viruses . They have independently evolved multiple times , and different classes of protease can perform the same reaction by completely different catalytic mechanisms . Proteases can be classified into seven broad groups: Proteases were first grouped into 84 families according to their evolutionary relationship in 1993, and classified under four catalytic types: serine , cysteine , aspartic , and metallo proteases. The threonine and glutamic proteases were not described until 1995 and 2004 respectively. The mechanism used to cleave

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468-434: 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. Ham is produced by curing raw pork by salting , also known as dry curing, or brining , also known as wet curing. Additionally, smoking may be employed, and seasonings may be added. Traditional dry cure hams may use only salt as

507-616: Is achieved by proteases having a long binding cleft or tunnel with several pockets that bind to specified residues. For example, TEV protease is specific for the sequence ...ENLYFQ\S... ('\'=cleavage site). Proteases, being themselves proteins, are cleaved by other protease molecules, sometimes of the same variety. This acts as a method of regulation of protease activity. Some proteases are less active after autolysis (e.g. TEV protease ) whilst others are more active (e.g. trypsinogen ). Proteases occur in all organisms, from prokaryotes to eukaryotes to viruses . These enzymes are involved in

546-704: Is found in the MEROPS database. In this database, proteases are classified firstly by 'clan' ( superfamily ) based on structure, mechanism and catalytic residue order (e.g. the PA clan where P indicates a mixture of nucleophile families). Within each 'clan', proteases are classified into families based on sequence similarity (e.g. the S1 and C3 families within the PA clan). Each family may contain many hundreds of related proteases (e.g. trypsin , elastase , thrombin and streptogrisin within

585-508: Is one of the fastest "switching on" and "switching off" regulatory mechanisms in the physiology of an organism. By a complex cooperative action, proteases can catalyze cascade reactions, which result in rapid and efficient amplification of an organism's response to a physiological signal. Bacteria secrete proteases to hydrolyse the peptide bonds in proteins and therefore break the proteins down into their constituent amino acids . Bacterial and fungal proteases are particularly important to

624-506: Is quicker than traditional brining, normally being completed in a few days. Wet-cured ham is usually cooked, either during processing, or after ageing. It is first brined, then cooked in a container and finally surface pasteurized. Italian regulations allow it to contain salt, nitrites, sugar, dextrose, fructose, lactose, maltodextrin, milk protein, soy protein, natural or modified starches, spices, gelatin, and flavorings. Ham can also be additionally preserved through smoking , in which

663-413: Is typically kept in the brine for around 3 to 14 days. Wet curing also has the effect of increasing volume and weight of the finished product, by about 4%. The wet curing process can also be achieved by pumping the curing solution into the meat. This can be quicker, increase the weight of the finished product by more than immersion, and ensure a more even distribution of salt through the meat. This process

702-413: Is unusual since, rather than hydrolysis , it performs an elimination reaction . During this reaction, the catalytic asparagine forms a cyclic chemical structure that cleaves itself at asparagine residues in proteins under the right conditions. Given its fundamentally different mechanism, its inclusion as a peptidase may be debatable. An up-to-date classification of protease evolutionary superfamilies

741-438: The hepatitis C virus and the picornaviruses ). These proteases (e.g. TEV protease ) have high specificity and only cleave a very restricted set of substrate sequences. They are therefore a common target for protease inhibitors . Archaea use proteases to regulate various cellular processes from cell-signaling , metabolism , secretion and protein quality control. Only two ATP-dependent proteases are found in archaea:

780-481: The AAA+ proteasome ) by degrading unfolded or misfolded proteins . A secreted bacterial protease may also act as an exotoxin, and be an example of a virulence factor in bacterial pathogenesis (for example, exfoliative toxin ). Bacterial exotoxic proteases destroy extracellular structures. The genomes of some viruses encode one massive polyprotein , which needs a protease to cleave this into functional units (e.g.

819-539: The Roman period, as evidenced by an import trade from Gaul mentioned by Marcus Terentius Varro in his writings. 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 began to refer to the cut of pork derived from the hind leg of a pig around the 15th century. Because of the preservation process, ham

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858-407: The S1 family). Currently more than 50 clans are known, each indicating an independent evolutionary origin of proteolysis. Alternatively, proteases may be classified by the optimal pH in which they are active: Proteases are involved in digesting long protein chains into shorter fragments by splitting the peptide bonds that link amino acid residues. Some detach the terminal amino acids from

897-575: The United Kingdom, a pork leg cut, either whole or sliced, that has been cured but requires additional cooking is known as gammon . Gammons were traditionally cured before being cut from a side of pork along with bacon . When cooked, gammon is ham. Cooked ham joints are a popular dish around Christmas time, particularly in the Anglosphere and Northern Europe. Gammon can also served as gammon steaks, which are fried or grilled, and served in

936-546: The United States, the Code of Federal Regulations (CFR) says that "the word 'ham', without any prefix indicating the species of animal from which derived, shall be used in labeling only in connection with the hind legs of swine". In addition to the main categories, some processing choices can affect legal labeling. For instance, in the United States, a "smoked" ham must have been smoked by hanging over burning wood chips in

975-563: The array of proteins ingested into smaller peptide fragments. Promiscuous proteases typically bind to a single amino acid on the substrate and so only have specificity for that residue. For example, trypsin is specific for the sequences ...K\... or ...R\... ('\'=cleavage site). Conversely some proteases are highly specific and only cleave substrates with a certain sequence. Blood clotting (such as thrombin ) and viral polyprotein processing (such as TEV protease ) requires this level of specificity in order to achieve precise cleavage events. This

1014-399: The body from excessive protease-triggered activation of its own complement system ), antithrombin (which protects the body from excessive coagulation ), plasminogen activator inhibitor-1 (which protects the body from inadequate coagulation by blocking protease-triggered fibrinolysis ), and neuroserpin . Natural protease inhibitors include the family of lipocalin proteins, which play

1053-448: The clots, and the correct action of the immune system. Other proteases are present in leukocytes ( elastase , cathepsin G ) and play several different roles in metabolic control. Some snake venoms are also proteases, such as pit viper haemotoxin and interfere with the victim's blood clotting cascade. Proteases determine the lifetime of other proteins playing important physiological roles like hormones, antibodies, or other enzymes. This

1092-427: The curative agent, although this is comparatively rare. This process involves cleaning the raw meat, covering it in salt while it is gradually pressed to squeeze out fluid. Specific herbs and spices may be used to add flavour during this step. The hams are then washed and hung in a dark, temperature-regulated place until dry. It is then hung to air for another period of time. The duration of the curing process varies by

1131-514: The formula, and has a discernible effect on flavor. So-called "lean" and "extra lean" hams must adhere to maximum levels of fat and cholesterol per 100 grams of product. Whole fresh pork leg can be labeled as fresh ham in the United States. A number of hams worldwide have some level of protection of their unique characteristics, usually relating to their method of preservation or location of production or processing. Dependent on jurisdiction, rules may prevent any other product being sold with

1170-489: The global carbon and nitrogen cycles in the recycling of proteins, and such activity tends to be regulated by nutritional signals in these organisms. The net impact of nutritional regulation of protease activity among the thousands of species present in soil can be observed at the overall microbial community level as proteins are broken down in response to carbon, nitrogen, or sulfur limitation. Bacteria contain proteases responsible for general protein quality control (e.g.

1209-428: The meat is placed in a smokehouse (or equivalent) to be cured by the action of smoke. The main flavor compounds of smoked ham are guaiacol , and its 4-, 5-, and 6-methyl derivatives as well as 2,6-dimethylphenol. These compounds are produced by combustion of lignin, a major constituent of wood used in the smokehouse. In many countries the term is now protected by statute, with a specific definition. For instance, in

Ham (disambiguation) - Misplaced Pages Continue

1248-591: The membrane associated LonB protease and a soluble 20S proteosome complex . The field of protease research is enormous. Since 2004, approximately 8000 papers related to this field were published each year. Proteases are used in industry, medicine and as a basic biological research tool. Digestive proteases are part of many laundry detergents and are also used extensively in the bread industry in bread improver . A variety of proteases are used medically both for their native function (e.g. controlling blood clotting) or for completely artificial functions ( e.g. for

1287-446: The nucleophile types have evolved convergently in different superfamilies , and some superfamilies show divergent evolution to multiple different nucleophiles. Metalloproteases, aspartic, and glutamic proteases utilize their active site residues to activate a water molecule, which then attacks the scissile bond. A seventh catalytic type of proteolytic enzymes, asparagine peptide lyase , was described in 2011. Its proteolytic mechanism

1326-518: The particular appellation, such as through the European protected geographical indication . Ham is typically used in its sliced form, often as a filling for sandwiches and similar foods, such as in the ham sandwich and ham and cheese sandwich . Other variations include toasted sandwiches such as the croque-monsieur and the Cubano . It is also a popular topping for pizza in the United States . In

1365-481: The process itself, conditions such as temperature, duration, water content, redox potential , and salt content all have an effect on the meat. The salt content in dry-cured ham varies throughout a piece of meat, with gradients determinable through sampling and testing or non-invasively through CT scanning . Wet-cured hams are brined , which involves the immersion of the meat in a brine , sometimes with other ingredients such as sugar also added for flavour. The meat

1404-467: The protein chain ( exopeptidases , such as aminopeptidases , carboxypeptidase A ); others attack internal peptide bonds of a protein ( endopeptidases , such as trypsin , chymotrypsin , pepsin , papain , elastase ). Catalysis is achieved by one of two mechanisms: Proteolysis can be highly promiscuous such that a wide range of protein substrates are hydrolyzed. This is the case for digestive enzymes such as trypsin , which have to be able to cleave

1443-582: The salt. Nitrites are used because they prevent bacterial growth and, in a reaction with the meat's myoglobin , give the product a desirable dark red color. The amount and mixture of salt and nitrites used have an effect on the shrinkage of the meat. Because of the toxicity of nitrite, some areas specify a maximum allowable content of nitrite in the final product. Under certain conditions, especially during cooking, nitrites in meat can react with degradation products of amino acids , forming nitrosamines , which are known carcinogens . The dry curing of ham involves

1482-580: The targeted degradation of pathogenic proteins). Highly specific proteases such as TEV protease and thrombin are commonly used to cleave fusion proteins and affinity tags in a controlled fashion. Protease-containing plant-solutions called vegetarian rennet have been in use for hundreds of years in Europe and the Middle East for making kosher and halal Cheeses . Vegetarian rennet from Withania coagulans has been in use for thousands of years as

1521-464: The type of ham. For example, Jinhua ham takes approximately 8 to 10 months to complete, jamón serrano cures in 9–12 months, prosciutto di Parma takes more than 12 months, and Iberian ham can take up to 2 years to reach the desired flavor characteristics. Many dry-cured hams, such as prosciutto , are eaten without being cooked. Most modern dry cure hams also use nitrites (either sodium nitrite or potassium nitrite ), which are added along with

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