{{Short description|Food preservation and flavouring processes}} {{For|post-harvest treatment of plant material|Curing (vegetable preservation)}}

[[File:ProsciuttoSeaSalt.JPG|thumb|Sea salt being added to raw ham to make prosciutto]] '''Curing''' is any of various food preservation and flavoring processes of foods such as meat, fish and vegetables, by the addition of salt, with the aim of drawing moisture out of the food by the process of osmosis. Because curing increases the solute concentration in the food and hence decreases its water potential, the food becomes inhospitable for the microbe growth that causes food spoilage. Curing can be traced back to antiquity, and was the primary method of preserving meat and fish until the late 19th century. Dehydration was the earliest form of food curing.<ref name="uog" /> Many curing processes also involve smoking, spicing, cooking, or the addition of combinations of sugar, nitrate, and nitrite.<ref name="uog">{{Cite web|first=Brian A.|last=Nummer|title=Historical Origins of Food Preservation|website=National Center for Home Food Preservation|url=https://nchfp.uga.edu/publications/nchfp/factsheets/food_pres_hist.html|access-date=2 January 2023|date=May 2002|archive-date=15 October 2011|archive-url=https://web.archive.org/web/20111015194629/http://www.uga.edu/nchfp/publications/nchfp/factsheets/food_pres_hist.html|url-status=dead}}</ref>

'''Meat preservation''' in general (of meat from livestock, game, and poultry) comprises the set of all treatment processes for preserving the properties, taste, texture, and color of raw, partially cooked, or cooked meats while keeping them edible and safe to consume. Curing has been the dominant method of meat preservation for thousands of years, although modern developments like refrigeration and synthetic preservatives have begun to complement and supplant it.

While meat-preservation processes like curing were mainly developed in order to prevent disease and to increase food security, the advent of modern preservation methods mean that in most developed countries {{as of|2018|alt=today}}, curing is instead mainly practiced for its cultural value and desirable impact on the texture and taste of food. For less-developed countries, curing remains a key process in the production, transport and availability of meat.

[[File:Prague powder No 1.jpg|thumb|186x186px|Curing salt, also known as "Prague powder" or "pink salt", is typically a combination of sodium chloride and sodium nitrite that is dyed pink to distinguish it from table salt.]] Some traditional cured meat (such as authentic Parma ham<ref>{{Cite web|url=https://www.curiouscook.com/site/2007/04/parma-and-iberian-hams-red-from-zinc.html|title=Parma and Iberian hams, red from zinc|website=Curious Cook|access-date=8 February 2019|last1=McGee|first1=Harold}}</ref> and some authentic Spanish chorizo and Italian salami) is cured with salt alone.<ref>{{Cite book|title=Cochonneries : comment la charcuterie est devenue un poison|last=Coudray|first=Guillaume|year=2017|isbn=9782707193582|location=Paris|oclc=1011036745}}</ref> Today, potassium nitrate (KNO<sub>3</sub>) and sodium nitrite (NaNO<sub>2</sub>) (in conjunction with salt) are the most common agents in curing meat, because they bond to the myoglobin and act as a substitute for oxygen,<ref name=Ulin2011>{{cite news |last1=Ulin |first1=Don |title=Why Meat Stays Red: Myoglobin And Nitrites |url=https://indianapublicmedia.org/amomentofscience/meat-stays-red-myoglobin-nitrites.php |work=A Moment of Science - Indiana Public Media |date=10 May 2011 }}</ref> thus turning myoglobin red.<ref name=Ulin2011/><ref>{{cite web |last1=Schweihofer |first1=Jeannine |title=Cured meat color: Part 3 |url=https://www.canr.msu.edu/news/cured_meat_color_part_3 |work=MSU Extension |date=21 October 2014 }}</ref> More recent evidence shows that these chemicals also inhibit the growth of the bacteria that cause the disease botulism.<ref name=Ulin2011/>

The combination of table salt with nitrates or nitrites, called curing salt, is often dyed pink to distinguish it from table salt.<ref name="Bitterman">{{cite book|title=Salted: A Manifesto on the World's Most Essential Mineral, with Recipes|last=Bitterman|first=M.|publisher=Random House|year=2010|isbn=978-1580082624|page=187|chapter=Salt Reference Guide|access-date=16 August 2013|chapter-url=https://books.google.com/books?id=8IAvgHk5SV4C&pg=PA187}}</ref> Neither table salt nor any of the nitrites or nitrates commonly used in curing (e.g., sodium nitrate [NaNO<sub>3</sub>],<ref name="Gisslen2006">{{cite book|title=Professional Cooking, College Version|last=Gisslen|first=W.|publisher=John Wiley & Sons|year=2006|isbn=9780471663744|location=Hoboken, NJ|page=827|chapter=Sausages and Cured Foods|access-date=16 August 2013|chapter-url=https://books.google.com/books?id=hxcH5o9QeywC&pg=PA827}}</ref> sodium nitrite,<ref name="Gisslen2006" /> and potassium nitrate<ref>{{Cite web |website=Meat Science |title=Information on sausages and sausage manufacture | publisher=University of Wisconsin | first = Dennis | last = Buege | year = 2001 |url=http://www.uwex.edu/ces/flp/meatscience/sausage.html|access-date=2 January 2023|archive-url=https://web.archive.org/web/20031223155710/http://www.uwex.edu/ces/flp/meatscience/sausage.html |archive-date=23 December 2003 }}</ref>) is naturally pink.

== Reasons for curing == Meat decomposes rapidly if it is not preserved. The speed of decomposition depends on several factors, including ambient humidity, temperature, and the presence of pathogens. Most types of untreated meat cannot be kept at room temperature for lengthy periods before spoiling.

Spoiled meat changes color and exudes a foul odor. Ingestion can cause serious food poisoning. Salt-curing processes were developed in antiquity<ref>{{Cite web|url=http://www.italianmade.com/usa/product/prosciutto-di-parma-pdo/|title=PROSCIUTTO DI PARMA PDO|website=Italian Made|language=en-US|access-date=8 February 2019}}</ref> in order to ensure food safety without relying on then unknown anti-bacterial agents.

The short shelf life of fresh meat does not pose significant problems when access to it is easy and supply is abundant. But in times of scarcity and famine, or when the meat must be transported over long distances, food preservation is necessary.

Curing significantly increases the length of time meat remains edible, by making it inhospitable to the growth of microbes.

== Chemical actions == === Salt === {{Main|Salting (food)}}

Salt (sodium chloride) is the primary ingredient used in meat curing.<ref name="ANSI-3994">{{cite report |url=http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-2055/ANSI-3994web.pdf |title=Oklahoma Cooperative Extension Service |last=Ray |first=Frederick K. |publisher=Oklahoma State University |access-date=15 December 2010}}</ref> Removal of water and addition of salt to meat creates a solute-rich environment where osmotic pressure draws water out of microorganisms, slowing down their growth.<ref name="ANSI-3994" /><ref name="mnstate-notes">{{cite web|title=Curing and Brining (food preservation)|url=http://www.mnstate.edu/provost/BCBT100%20Curing%20and%20Brining.pdf|work=Science of Cooking|publisher=Minnesota State University|access-date=15 December 2010|archive-date=27 September 2011|archive-url=https://web.archive.org/web/20110927015916/http://www.mnstate.edu/provost/BCBT100%20Curing%20and%20Brining.pdf|url-status=dead}}</ref> Doing this requires a concentration of salt of nearly 20%.<ref name="mnstate-notes" />

In sausage production, salt causes the soluble proteins to come to the surface of the meat that was used to make the sausages. These proteins coagulate when the sausage is heated, helping to hold the sausage together.<ref name="uga-sausage">{{cite web|title=Curing & Smoking|url=http://www.uga.edu/nchfp/how/cure_smoke/sausage_ingredients.html|work=National Center for Home Food Preservation|publisher=University of Georgia|access-date=15 December 2010|archive-url=https://web.archive.org/web/20100530132750/http://www.uga.edu/nchfp/how/cure_smoke/sausage_ingredients.html|archive-date=30 May 2010|url-status=dead}}</ref>

=== Sugar === The sugar added to meat for curing purposes comes in many forms, including honey, corn syrup solids, and maple syrup.<ref name="IL-state-additives">{{cite web|title=Additives Used in Meat|url=http://labs.ansci.illinois.edu/meatscience/Library/additives.htm|work=Meat Science|publisher=Illinois State University|access-date=16 December 2010|archive-url=https://web.archive.org/web/20100502013024/http://labs.ansci.illinois.edu/meatscience/Library/additives.htm|archive-date=2 May 2010|url-status=dead}}</ref> However, with the exception of bacon, it does not contribute much to the flavor,<ref name="uga-smoke-cure">{{cite web|title=Smoking and Curing|url=http://www.uga.edu/nchfp/publications/nchfp/lit_rev/cure_smoke_cure.html|work=The National Center for Home Food Preservation|publisher=University of Georgia|access-date=16 December 2010|archive-date=5 June 2010|archive-url=https://web.archive.org/web/20100605162845/http://www.uga.edu/nchfp/publications/nchfp/lit_rev/cure_smoke_cure.html|url-status=dead}}</ref> but it does alleviate the harsh flavor of the salt.<ref name="ANSI-3994" /> Sugar also contributes to the growth of beneficial bacteria such as ''Lactobacillus'' by feeding them.<ref name="edinformatics">{{cite web|title=What Is Curing?|url=http://www.edinformatics.com/math_science/science_of_cooking/curing_foods.htm|work=Science of Cooking|publisher=EDinformatics|access-date=16 December 2010}}</ref>

=== Nitrates and nitrites === thumb|Nitrosyl-heme Nitrates and nitrites extend shelf life,{{cn|date=April 2021}} help kill bacteria, produce a characteristic flavor and give meat a pink or red color.<ref name="Edinformatics" /> Nitrite ({{chem|N|O|2|-}}) is generally supplied by sodium nitrite or (indirectly) by potassium nitrate. Nitrite salts are most often used to accelerate curing and impart a pink colour.<ref name="Wilson" /> Nitrate is specifically used only in a few curing conditions and products where nitrite (which may be generated from nitrate) must be generated in the product over long periods of time.

Nitrite further breaks down in the meat into nitric oxide (NO), which then binds to the iron atom in the center of myoglobin's heme group, reducing oxidation and causing a reddish-brown color ({{chem name|nitrosomyoglobin}}) when raw and the characteristic cooked-ham pink color ({{chem name|nitrosohemochrome}} or nitrosyl-heme) when cooked. The addition of ascorbate to cured meat reduces formation of nitrosamines (see below), but increases the nitrosylation of iron.

The use of nitrite and nitrate salts for meat in the US has been formally used since 1925.{{citation needed|date=April 2017}} Because of the relatively high toxicity of nitrite (the lethal dose in humans is about 22&nbsp;mg/kg of body weight), the maximum allowed nitrite concentration in US meat products is 200 ppm. Plasma nitrite is reduced in persons with endothelial dysfunction.<ref name="pmid16413411">{{cite journal |vauthors=Kleinbongard P, Dejam A, Lauer T, Jax T, Kerber S, Gharini P, Balzer J, Zotz RB, Scharf RE, Willers R, Schechter AN, Feelisch M, Kelm M | title=Plasma nitrite concentrations reflect the degree of endothelial dysfunction in humans | journal= Free Radical Biology and Medicine | volume=40 | issue=2 | year=2006 | pages=295–302 | pmid=16413411 | doi=10.1016/j.freeradbiomed.2005.08.025}}</ref>

Nitrite-containing processed meat is associated with increased risk of developing colorectal cancer.<ref>{{cite journal |last1=Crowe |first1=William |last2=Elliott |first2=Christopher T. |last3=Green |first3=Brian D. |title=A Review of the In Vivo Evidence Investigating the Role of Nitrite Exposure from Processed Meat Consumption in the Development of Colorectal Cancer |journal=Nutrients |date=5 November 2019 |volume=11 |issue=11 |pages=2673 |doi=10.3390/nu11112673 |pmid=31694233 |pmc=6893523 |doi-access=free }}</ref> Adding nitrites to meat has been shown to generate known carcinogens such as nitrosamines, ''N''-nitrosamides<ref>{{cite journal |last1=Inoue-Choi |first1=Maki |last2=Sinha |first2=Rashmi |last3=Gierach |first3=Gretchen L. |last4=Ward |first4=Mary H. |title=Red and processed meat, nitrite, and heme iron intakes and postmenopausal breast cancer risk in the NIH-AARP Diet and Health Study |journal=International Journal of Cancer |date=1 April 2016 |volume=138 |issue=7 |pages=1609–1618 |doi=10.1002/ijc.29901 |pmid=26505173 |pmc=4724256 }}</ref> and nitrosyl-heme, resulting from nitrosylation reactions; the World Health Organization (WHO) advises that each {{convert|50|g|abbr=on}} of "processed meats" eaten a day would raise the risk of getting bowel cancer by 18% over a lifetime; "processed meat" refers to meat that has been transformed through salting, curing, fermentation, smoking, or other processes to enhance flavour or improve preservation. The World Health Organization's review of more than 400 studies concluded, in 2015, that there was sufficient evidence that "processed meats" caused cancer, particularly colon cancer; the WHO's International Agency for Research on Cancer classified "processed meats" as carcinogenic to humans (Group 1).<ref name="Wilson">{{cite news |last=Wilson |first=Bee |date=1 March 2018 |title=Yes, bacon really is killing us |url=https://www.theguardian.com/news/2018/mar/01/bacon-cancer-processed-meats-nitrates-nitrites-sausages |url-status=live |work=The Guardian |location=London |archive-url=https://web.archive.org/web/20210210183650/https://www.theguardian.com/news/2018/mar/01/bacon-cancer-processed-meats-nitrates-nitrites-sausages |archive-date=10 February 2021 |access-date=14 February 2021 |quote=In trade journals of the 1960s, the firms who sold nitrite powders to ham-makers spoke quite openly about how the main advantage was to increase profit margins by speeding up production.}}</ref><ref name="IARC2015">{{cite web |title=IARC Monographs evaluate consumption of red meat and processed meat |url=https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf |publisher=International Agency for Research on Cancer |date=26 October 2015 |access-date=14 February 2021 |archive-date=18 January 2021 |archive-url=https://web.archive.org/web/20210118044116/https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf |quote=Processed meat was classified as carcinogenic to humans (Group 1), based on sufficient evidence in humans that the consumption of processed meat causes colorectal cancer.}}</ref>

The use of nitrites in food preservation is highly controversial<ref>{{Cite web|url=https://www.newfoodmagazine.com/article/138892/nitrate-use-in-the-meat-industry/|title = Why is our meat still being poisoned by nitrates?}}</ref> due to the potential for the formation of nitroso-compounds such as nitrosamines, ''N''-nitrosamides and nitrosyl-heme.{{cn|date=April 2021}} When the meat is cooked at high temperatures, nitrite-cured meat products can also lead to the formation of nitrosamines.<ref name="Edinformatics">{{cite web|url=http://www.edinformatics.com/math_science/science_of_cooking/curing_foods.htm|title=Curing Food|publisher=Edinformatics|access-date=21 February 2010}}</ref><ref>{{cite journal |last1=Flores |first1=Mónica |last2=Mora |first2=Leticia |last3=Reig |first3=Milagro |last4=Toldrá |first4=Fidel |title=Risk assessment of chemical substances of safety concern generated in processed meats |journal=Food Science and Human Wellness |date=1 September 2019 |volume=8 |issue=3 |pages=244–251 |doi=10.1016/j.fshw.2019.07.003 |doi-access=free |hdl=10261/197361 |hdl-access=free }}</ref> The effect is seen for red processed meat, but not for white meat or fish.<ref name="pmid17956350">{{cite journal |last1=Kuhnle |first1=G.G.C. |last2=Bingham |first2=S.A. |title=Dietary meat, endogenous nitrosation and colorectal cancer |journal=Biochemical Society Transactions |date=1 November 2007 |volume=35 |issue=5 |pages=1355–1357 |doi=10.1042/BST0351355 |pmid=17956350 |s2cid=29766026 }}</ref><ref name="pmid12421881">{{cite journal |last1=Bingham |first1=Sheila Anne |last2=Hughes |first2=Roisin |last3=Cross |first3=Amanda Jane|author3-link=Amanda Cross (scientist) |title=Effect of White Versus Red Meat on Endogenous N-Nitrosation in the Human Colon and Further Evidence of a Dose Response |journal=The Journal of Nutrition |date=1 November 2002 |volume=132 |issue=11 |pages=3522S–3525S |doi=10.1093/jn/132.11.3522S |pmid=12421881 |doi-access=free }}</ref> Nitrates and nitrites may cause cancer and the production of carcinogenic nitrosamines can be potently inhibited by the use of the antioxidants vitamin C and the alpha-tocopherol form of vitamin E during curing.<ref name="pmid22464105">{{cite journal |last1=Parthasarathy |first1=Deepa K. |last2=Bryan |first2=Nathan S. |title=Sodium nitrite: The 'cure' for nitric oxide insufficiency |journal=Meat Science |date=November 2012 |volume=92 |issue=3 |pages=274–279 |doi=10.1016/j.meatsci.2012.03.001 |pmid=22464105 }}</ref> Under simulated gastric conditions, nitrosothiols rather than nitrosamines are the main nitroso species being formed.<ref name="pmid17956350" /> The use of either compound is therefore regulated; for example, in the United States, the concentration of nitrates and nitrites is generally limited to 200 ppm or lower.<ref name="Edinformatics" />

The meat industry considers nitrites irreplaceable because they speed up curing and improve color while retarding the growth of ''Clostridium botulinum'',<ref name="Wilson" /> the bacteria that causes botulism. Botulism, however, is an extremely rare disease (less than 1000 cases per year reported worldwide) and is almost always associated with home preparations of preserved food.<ref name="Botulism">{{cite web |url=https://www.cdc.gov/botulism/index.html |title=Botulism |website=Centers for Disease Control and Prevention |access-date=30 September 2018}}</ref><ref name="Wilson" /> For example, all Parma ham has been made without nitrites since 1993, but was reported in 2018 to have caused no cases of botulism.<ref name="Wilson" />

Furthermore, while the FDA has set a limit of 200 ppm of nitrates for cured meat, they are not allowed and not recognized as safe by the FDA in most other foods, even foods that are not cooked at high temperatures, such as cheese.<ref>{{cite web |url=https://www.accessdata.fda.gov/cms_ia/importalert_10.html |title=Import Alert 12-12 |website=U.S. Food & Drug Administration |access-date=30 September 2018 |archive-date=24 December 2017 |archive-url=https://web.archive.org/web/20171224050625/https://www.accessdata.fda.gov/cms_ia/importalert_10.html |url-status=dead }}</ref>

=== Nitrites from celery === Processed meats without "added nitrites" may be misleading as they may be using naturally occurring nitrites from celery instead.<ref>{{cite news |last1=Choi |first1=Candice |title=Experts say hot dogs minus artificial nitrites may be no better |url=http://www.chicagotribune.com/news/nationworld/science/ct-hot-dogs-nitrites-20170630-story.html |access-date=2 October 2018 |work=Chicago Tribune |date=30 June 2017}}</ref>

A 2019 report from ''Consumer Reports''<ref>{{cite news |last1=Calvo |first1=Trisha |title=Danger at the Deli |url=https://www.consumerreports.org/deli-meats/danger-at-the-deli-cold-cuts-increased-risk-cancer-heart-disease/ |access-date=31 August 2019 |work=Consumer Reports |date=29 August 2019}}</ref> found that using celery (or other natural sources) as a curing agent introduced naturally occurring nitrates and nitrites. The USDA allows the term "uncured" or "no nitrates or nitrites added" on products using these natural sources of nitrites, which provides the consumer a false sense of making a healthier choice. The ''Consumer Reports'' investigation also provides the average level of sodium, nitrates and nitrites found per gram of meat in their report.

''Consumer Reports'' and the Center for Science in the Public Interest filed a formal request to the USDA to change the labeling requirements in 2019.<ref>{{cite news |last1=Aubrey |first1=Allison |title=Duped In The Deli Aisle? 'No Nitrates Added' Labels Are Often Misleading |url=https://www.npr.org/sections/thesalt/2019/08/29/755115208/duped-in-the-deli-aisle-no-nitrates-added-labels-are-often-misleading |access-date=31 August 2019 |work=NPR |date=29 August 2019 }}</ref>

=== Smoke === {{Main|Smoking (cooking)}}

Meat can also be preserved by "smoking". If the smoke is hot enough to slow-cook the meat, this will also keep it tender.<ref>{{cite web|title=Smoking Meat and Poultry|url=http://www.fsis.usda.gov/factsheets/Smoking_Meat_and_Poultry/index.asp|work=Fact Sheets|publisher=United States Department of Agriculture|access-date=27 January 2011|archive-url=https://web.archive.org/web/20101017064122/http://www.fsis.usda.gov/factsheets/Smoking_Meat_and_Poultry/index.asp|archive-date=17 October 2010|url-status=dead}}</ref> One method of smoking calls for a smokehouse with damp wood chips or sawdust.<ref name="wsu-smoke">{{cite web|last=Busboom|first=Jan R.|title=Curing and Smoking Poultry Meat|url=http://cru.cahe.wsu.edu/CEPublications/eb1660/eb1660.pdf|publisher=Washington State University|access-date=27 January 2011|archive-url=https://web.archive.org/web/20110720121952/http://cru.cahe.wsu.edu/CEPublications/eb1660/eb1660.pdf|archive-date=20 July 2011|url-status=dead}}</ref> In North America, hardwoods such as hickory, mesquite, and maple are commonly used for smoking, as are the wood from fruit trees such as apple, cherry, and plum, and even corncobs.

Smoking helps seal the outer layer of the food being cured, making it more difficult for bacteria to enter. It can be done in combination with other curing methods such as salting. Common smoking styles include hot smoking, smoke roasting (pit barbecuing) and cold smoking. Smoke roasting and hot smoking cook the meat while cold smoking does not. If the meat is cold smoked, it should be dried quickly to limit bacterial growth during the critical period where the meat is not yet dry. This can be achieved, as with jerky, by slicing the meat thinly.

The smoking of food directly with wood smoke is known to contaminate the food with carcinogenic polycyclic aromatic hydrocarbons.<ref>{{cite book |doi=10.1159/000387467 |chapter=Smoked Food and Cancer |title=Foreign Substances and Nutrition |series=Forum of Nutrition |year=1980 |last1=Fritz |first1=W. |last2=Soós |first2=K. |volume=29 |issue=29 |pages=57–64 |pmid=7447916 |isbn=978-3-8055-0621-2 }}</ref>

=== Research === Since the 20th century, with respect to the relationship between diet and human disease (e.g. cardiovascular, etc.), scientists have conducted studies on the effects of lipolysis on vacuum-packed or frozen meat. In particular, by analyzing entrecôtes of frozen beef during 270 days at {{convert|-20|°C}}, scientists found an important phospholipase that accompanies the loss of some unsaturated fat n-3 and n-6, which are already low in the flesh of ruminants.<ref>{{cite journal |last1=Bauchart |first1=Dominique |last2=Thomas |first2=E. |last3=Scislowski |first3=V. |last4=Peyron |first4=Alain |last5=Durand |first5=Denys |date=4 October 2006 |title=Effets des modes de conservation de la viande bovine sur les lipides et leur contenu en acides gras polyinsaturés |trans-title=Effects of beef preservation methods on lipids and their polyunsaturated fatty acid content |url=https://hal.inrae.fr/hal-02755491 |journal=Journées Sciences du Muscle et Technologies des Viandes |language=French |volume=Hors-Série |id={{INIST|18356301}}}}</ref>

== Health effects == Elevated levels of nitrites in preserved meats increase the risk of nasopharyngeal cancer.<ref name=":8">{{Cite journal |last1=Barsouk |first1=Adam |last2=Aluru |first2=John Sukumar |last3=Rawla |first3=Prashanth |last4=Saginala |first4=Kalyan |last5=Barsouk |first5=Alexander |date=2023-06-13 |title=Epidemiology, Risk Factors, and Prevention of Head and Neck Squamous Cell Carcinoma |journal=Medical Sciences |language=en |volume=11 |issue=2 |page=42 |doi=10.3390/medsci11020042 |issn=2076-3271 |pmc=10304137 |pmid=37367741 |doi-access=free}}</ref>

In 2015, the International Agency for Research on Cancer of the World Health Organization classified processed meat, that is, meat that has undergone salting, curing, fermenting, or smoking, as "carcinogenic to humans".<ref>{{cite web |author=Stacy Simon |date=26 October 2015 |title=World Health Organization Says Processed Meat Causes Cancer |url=http://www.cancer.org/cancer/news/news/world-health-organization-says-processed-meat-causes-cancer |url-status=dead |archive-url=https://web.archive.org/web/20170107043239/http://www.cancer.org/cancer/news/news/world-health-organization-says-processed-meat-causes-cancer |archive-date=7 January 2017 |access-date=18 December 2015 |work=Cancer.org}}</ref><ref>{{cite news |last1=Gallagher |first1=James |date=26 October 2015 |title=Processed meats do cause cancer - WHO |url=https://www.bbc.co.uk/news/health-34615621 |work=BBC News}}</ref><ref name="IARC2015" />

== History == A survival technique since prehistory, the preservation of meat has become, over the centuries, a topic of political, economic, and social importance worldwide.

=== Traditional methods === [[File:Sacrifice pig Tarporley Painter MAN.jpg|thumb|alt=Sur un fond noir se détache le profil ocre d’un jeune homme tenant de la main gauche le groin d’une tête de porc posée sur un tabouret, et de la droite un long couteau, haut levé et près à s’abattre sur la hure.|upright=0.8|Young man preparing a pig's head after a sacrifice. Vase v.&nbsp;360–340 BC, National Archaeological Museum of Spain.]]

Food curing dates back to ancient times, both in the form of smoked meat and salt-cured meat.<ref name="ANSI-3994" />

Several sources describe the salting of meat in the ancient Mediterranean world. Diodore of Sicily in his ''Bibliotheca historica'' wrote that the Cosséens<ref>A nomadic shepherd people, considered by classical authors to be made up of warriors'' et de brigands''; the object of a victorious campaign by Alexander the Great in the fourth century.<br />{{Cite journal |last=Francfort |first=Henri-Paul |date=1984 |title=Pierre Briant : État et pasteurs au Moyen-Orient ancien |url=https://www.persee.fr/doc/befeo_0336-1519_1984_num_73_1_1647 |journal=Bulletin de l'École française d'Extrême-Orient |language=fr |volume=73 |issue=1 |pages=369–384}}</ref> in the mountains of Persia salted the flesh of carnivorous animals.<ref>Diodore de Sicile, ''Bibliothèque historique'', XIX, 19 cité par Koehler, 1832, p.&nbsp;432, note 724 (p.&nbsp;486).</ref> Strabo indicates that people at Borsippa were catching bats and salting them to eat.<ref>Strabon, ''Géographie'', XVI, 1.7.</ref> The ancient Greeks prepared ''tarichos'' ({{Lang|grc|τάριχος}}), which was meat and fish conserved by salt or other means.{{efn|1= In time the original term came to mean salted fish only, whereas salted meat was called ''kreas tarichēron'' ({{Lang|grc|κρέας ταριχηρὸν}}), according to Athenaeus of Naucratis in his ''Deipnosophistae'', IV, 14.137f ([http://remacle.org/bloodwolf/erudits/athenee/livre4.htm#137f en ligne])}} The Romans called this dish ''{{Lang|la|salsamentum}}'' – which term later included salted fat, the sauces and spices used for its preparation.<ref name="Koehler">{{in lang|fr}} M. Koehler, ''Tarichos ou recherches sur l’histoire et les antiquités des pêcheries de la Russie méridionale'', in ''Mémoires de l’Académie impériale des sciences de Saint-Pétersbourg'', 6th series, book I, Imp. of the Académie impériale des sciences, Saint Petersburg, 1832, p.&nbsp;347 à 490 ([https://books.google.com/books?id=zH0-AAAAcAAJ&pg=PA347 en ligne]).</ref> Also evidence of ancient sausage production exists. The Roman gourmet Apicius speaks of a sausage-making technique involving ''{{Lang|grc|œnogaros}}'' (a mixture of the fermented fish sauce {{Lang|la|garum}} with oil or wine).<ref>{{in lang|la}} Apicii Coelii, ''{{Lang|la|De opsoniis et condimentis, sive arte coquinaria, libri decem. Cum annotationibus Martini Lister}}'', Londres, 1705, livre II, ch. 2, p.&nbsp;59.</ref> Preserved meats were furthermore a part of religious traditions: resulting meat for offerings to the gods was salted before being given to priests, after which it could be picked up again by the offerer, or even sold in the butcher's.<ref name="Koehler" />

A trade in salt meat occurred across ancient Europe. In Polybius's time ({{Circa}} 200 – {{Circa}}118 BCE),<ref>{{Cite book |last=Marquardt |first=Joachim |url=https://archive.org/stream/manueldesantiqui15mommuoft#page/54/mode/1up |title=La Vie Privée des Romains part 2: Travail et Loisirs |date=1893 |publisher=Thorin et Fils |editor-last=Humbert |editor-first=Gustave Amédée |series=Manuel des antiquités romaines |volume=XV |place=Paris |pages=52–56, esp. p 54 |language=fr}}</ref> the Gauls exported salt pork each year to Rome in large quantities, where it was sold in different cuts: rear cuts, middle cuts, hams, and sausages. This meat, after having been salted with the greatest care, was sometimes smoked. These goods had to have been considerably important, since they fed part of the Roman people and the armies. The Belgae were celebrated above all for the care which they gave to the fattening of their pigs. Their herds of sheep and pigs were so many, they could provide skins and salt meat not only for Rome, but also for most of Italy.{{citation needed|date=September 2018}} The Ceretani of Spain drew a large export income from their hams, which were so succulent, they were in no way inferior to those of Cantabria. These ''{{Lang|grc|tarichos}}'' of pig became especially sought, to the point that the ancients considered this meat the most nourishing of all and the easiest to digest.<ref name="Koehler" />

In Ethiopia, according to Pliny,<ref>Pliny, ''Histoire naturelle'', VI, 35.17</ref>{{Clarify|reason=Which Pliny?|date=April 2022}} and in Libya according to Saint Jerome, the Acridophages (literally, the locust-eaters) salted and smoked the crickets which arrived at their settlements in the spring in great swarms and which constituted, it was said, their sole food.

The smoking of meat was a traditional practice in North America, where Plains Indians hung their meat at the top of their tipis to increase the amount of smoke coming into contact with the food.<ref name="ANSI-3994" />

=== Middle Ages === In Europe, medieval cuisine made great use of meat and vegetables, and the guild of butchers was amongst the most powerful. During the 12th century,<ref>En Normandie par example : Léopold Delisle, ''Études historiques et archéologiques en province depuis 1848'' cité dans la ''Revue des deux mondes'', XI (XXI<sup>e</sup> année), Paris, 1851, p.&nbsp;1048.</ref> salt beef was consumed by all social classes. Smoked meat was called ''carbouclée'' in Romance tongues<ref>Jean-Baptiste-Bonaventure de Roquefort, ''Supplément au glossaire de la langue romane'', Chasseriau et Hécart, Paris, 1820, 308 pages</ref> and ''bacon'' if it was pork.<ref>Jean Baptiste Bonaventure de Roquefort, ''Glossaire de la langue romane'', T. I, B. Warée, Paris, 1808, 772 pages</ref>

The Middle Ages made pâté a masterpiece: that which is, in the 21st century, merely spiced minced meat (or fish), baked in a terrine and eaten cold, was at that time composed of a dough envelope stuffed with varied meats and superbly decorated for ceremonial feasts. The first French recipe, written in verse by Gace de La Bigne, mentions in the same pâté three great partridges, six fat quail, and a dozen larks. ''Le Ménagier de Paris'' mentions pâtés of fish, game, young rabbit, fresh venison, beef, pigeon, mutton, veal, and pork, and even pâtés of lark, turtledove, baby bird, goose, and hen. Bartolomeo Sacchi, called Platine, prefect of the Vatican Library, gives the recipe for a pâté of wild beasts: the flesh, after being boiled with salt and vinegar, was larded and placed inside an envelope of spiced fat, with a ''mélange'' of pepper, cinnamon and pounded lard; one studded the fat with cloves until it was entirely covered, then placed it inside a pâte.

In the 16th century, the most fashionable pâtés were of woodcock, au bec doré, chapon, beef tongue, cow feet, sheep feet, chicken, veal, and venison.<ref>Paul Lacroix et Ferdinand Séré, ''Le Moyen Âge et la Renaissance, histoire et description des mœurs et usages, du commerce et de l’industrie, des sciences, des arts, des littératures et des beaux-arts en Europe'', T. I, ch. ''Nourriture et cuisine'', Paris, 1848, not paginated.</ref> In the same era, Pierre Belon notes that the inhabitants of Crete and Chios lightly salted then oven-dried entire hares, sheep, and roe deer cut into pieces, and that in Turkey, cattle and sheep, cut and minced rouelles, salted then dried, were eaten on voyages with onions and no other preparation.<ref>Pierre Belon, ''Voyage au Levant, les observations de Pierre Belon du Mans, de plusieurs singularités et choses mémorables, trouvées en Grèce, Turquie, Judée, Égypte, Arabie et autres pays estranges'', 1553.</ref>

=== Early modern era === [[File:Civil War rations.jpg|thumb|alt=Derrière une grille de métal, des barils sont couchés, empilés en trois étages et cette pyramide se termine par des tonneaux de bœuf salé.|Barrels of salt beef and other products in a reconstruction of an American Civil War stockpile, at Fort Macon State Park, North Carolina]]

During the Age of Discovery, salt meat was one of the main foods for sailors on long voyages, for instance in the merchant marine or the navy. In the 18th century, salted Irish beef, transported in barrels, were considered finest.<ref>Daniel Gilles et Guy Pessiot, ''Voiles en Seine 99. L’armada du siècle'', Ptc, 1999, {{ISBN|2906258547}}, p.&nbsp;110.</ref>

Scientific research on meat by chemists and pharmacists led to the creation of a new, extremely practical product: meat extract, which could appear in different forms. The need to properly feed soldiers during long campaigns outside the country, such as in the Napoleonic Wars, and to nourish a constantly growing population often living in appalling conditions drove scientific research, but a confectioner, Nicolas Appert, in 1795 developed through experimentation a method which became universal and in one language bears his name: airtight storage, called ''{{lang|fr|appertisation}}'' in French.

With the spread of ''appertisation'', the 19th-century world entered the era of the "food industry", which developed new products such as canned salt meat (for example corned beef). The desire for safer food led to the creation of the US's Pure Food and Drug Act in 1906, followed by the national agencies for health security and the establishment of food traceability over the course of the 20th century.{{citation needed|date=April 2017}} It also led to continuing technological innovation.

In France, the summer of 1857 was so hot that most butchers refused to slaughter animals and charcutiers lost considerable amounts of meat, due to inadequate conservation methods. A member of the Academy of Medicine and his son issued a 34-page summary of works completed by 1857, which proposed some solutions: not less than 91 texts exist, of which 64 edited for only the years between 1851 and 1857.<ref name="Chevallier">{{in lang|fr}} A. Chevallier père et fils, ''Recherches chronologiques sur les moyens appliqués à la conservation des substances alimentaires de nature animale et de nature végétale'', in ''Annales d’hygiène publique et de médecine légale'', 2nd series, T. VIII, J.-B. Baillière et fils, Paris, 1857, 480 pages, p.&nbsp;291 – 324.</ref>

=== Effects on trade === The improvement of methods of meat preservation, and of the means of transport of preserved products, has notably permitted the separation of areas of production and areas of consumption, which can now be distant without it posing a problem, permitting the exportation of meats.

For example, the appearance in the 1980s of preservation techniques under controlled atmosphere sparked a small revolution in the world's market for sheep meat: the lamb of New Zealand, one of the world's largest exporters of lamb, could henceforth be sold as fresh meat, since it could be preserved from 12 to 16 weeks, which was a sufficient duration for it to reach Europe by boat. Before, meat from New Zealand was frozen, thus had a much lower value on European shelves. With the arrival of the new "chilled" meats, New Zealand could compete even more strongly with local producers of fresh meat.<ref>{{cite web |year=2004 |title=Les marchés à l'importation |url=http://www.ficow.be/ficow.site/wp-content/Uploads/Mar2.pdf |url-status=dead |archive-url=https://web.archive.org/web/20160922191446/http://www.ficow.be/ficow.site/wp-content/Uploads/Mar2.pdf |archive-date=22 September 2016 |access-date=21 July 2010}}</ref> The use of controlled atmosphere to avoid the depreciation which affects frozen meat is equally useful in other meat markets, such as that for pork, which now also enjoys an international trade.<ref>{{cite journal |last1=Trégaro |first1=Yves |year=2003 |title=Exportations françaises de viande de porc et stratégies des opérateurs nationaux |trans-title=French exports of pigmeat and strategies of national operators |url=http://www.journees-recherche-porcine.com/texte/2003/03txtEco/ec0305.pdf |journal=Journées de la recherche porcine |language=French |volume=35 |pages=217–222}}</ref>

== See also == {{portal|Food}} {{div col|colwidth=30em}}

* {{annotated link|Biltong}} {{div col end}} * {{annotated link|Brining}} * {{annotated link|Ceviche}} * {{annotated link|Charcuterie}} * {{annotated link|Cured fish}} * {{annotated link|Curing salt}} * {{annotated link|Fermentation in food processing}} * {{annotated link|List of dried foods}} * {{annotated link|List of smoked foods}} * {{annotated link|Pickling}} * {{annotated link|Sausage making}}

== Notes == {{notelist}}

== References == {{Reflist|2}}

== Further reading == {{refbegin}} * Bertolli, Paul. ''Cooking by Hand''. New York, NY: Clarkson Potter/Publishers, 2003. {{ISBN|0-609-60893-2}} * McGee, Harold. ''On Food and Cooking'' (revised). New York, NY: Scribner, 2004. {{ISBN|0-684-80001-2}} * National Research Council Academy of Life Sciences. "The Health Effects of Nitrate, Nitrite and N-Nitroso Compounds". Washington DC: National Academy Press, 1981. * [https://web.archive.org/web/20000708014235/http://www.the-scientist.com/yr1999/mar/watanabe_p1_990315.html Article in The Scientist, Volume 13, No. 6:1, Mar. 15, 1999 (registration required)].{{dead link|looks like should be one of the articles in this March 1999 issue https://www.the-scientist.com/magazine/issue/march-1999-13-5 |date=April 2021}} * [https://web.archive.org/web/20120502142847/http://www.meatprocessingforum.com/ Post on April 29, 2012 "Making Cured Meats"] {{refend}}

== External links == {{wikt | cure}} * [http://nchfp.uga.edu/publications/nchfp/lit_rev/cure_smoke_cure.html National Center for Home Food Preservation – Curing Foods] {{Webarchive|url=https://web.archive.org/web/20180124073339/http://nchfp.uga.edu/publications/nchfp/lit_rev/cure_smoke_cure.html |date=2018-01-24 }} * [https://nchfp.uga.edu/how/cure_smoke.html National Center for Home Food Preservation – How Do I? Curing and Smoking]

{{Food preservation}} {{Cooking techniques}} {{Consumer Food Safety}} {{Meat|state=expanded}}

{{DEFAULTSORT:Curing}} Category:Meat Category:Food preservation Category:Cooking techniques Category:Culinary terminology Category:Garde manger