
Processed meat is considered to be any
meat
Meat is animal Tissue (biology), tissue, often muscle, that is eaten as food. Humans have hunted and farmed other animals for meat since prehistory. The Neolithic Revolution allowed the domestication of vertebrates, including chickens, sheep, ...
that has been
modified in order to either improve its taste or to extend its
shelf life
Shelf life is the length of time that a commodity may be stored without becoming unfit for use, consumption, or sale. In other words, it might refer to whether a commodity should no longer be on a pantry shelf (unfit for use), or no longer on a s ...
. Methods of
meat processing include
salting,
curing,
fermentation
Fermentation is a type of anaerobic metabolism which harnesses the redox potential of the reactants to make adenosine triphosphate (ATP) and organic end products. Organic molecules, such as glucose or other sugars, are catabolized and reduce ...
,
smoking
Smoking is a practice in which a substance is combusted, and the resulting smoke is typically inhaled to be tasted and absorbed into the bloodstream of a person. Most commonly, the substance used is the dried leaves of the tobacco plant, whi ...
, and the addition of chemical
preservatives. Processed meat is frequently made from
pork
Pork is the culinary name for the meat of the pig (''Sus domesticus''). It is the most commonly consumed meat worldwide, with evidence of pig animal husbandry, husbandry dating back to 8000–9000 BCE.
Pork is eaten both freshly cooke ...
or
beef
Beef is the culinary name for meat from cattle (''Bos taurus''). Beef can be prepared in various ways; Cut of beef, cuts are often used for steak, which can be cooked to varying degrees of doneness, while trimmings are often Ground beef, grou ...
, but also
poultry
Poultry () are domesticated birds kept by humans for the purpose of harvesting animal products such as meat, Eggs as food, eggs or feathers. The practice of animal husbandry, raising poultry is known as poultry farming. These birds are most typ ...
and others. It can contain
meat by-products such as
blood
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells.
Blood is com ...
. Processed meat products include
bacon
Bacon is a type of Curing (food preservation), salt-cured pork made from various cuts of meat, cuts, typically the pork belly, belly or less fatty parts of the back. It is eaten as a side dish (particularly in breakfasts), used as a central in ...
,
ham,
sausage
A sausage is a type of meat product usually made from ground meat—often pork, beef, or poultry—along with salt, spices and other flavourings. Other ingredients, such as grains or breadcrumbs, may be included as fillers or extenders.
...
s,
salami,
corned beef,
jerky,
hot dog
A hot dog is a grilled, steamed, or boiled sausage served in the slit of a partially sliced bun. The term ''hot dog'' can also refer to the sausage itself. The sausage used is a wiener ( Vienna sausage) or a frankfurter ( Frankfurter Würs ...
s,
lunch meat,
canned meat,
chicken nuggets, and meat-based sauces. ''Meat processing'' includes all the processes that change fresh meat, with the exception of simple mechanical processes such as cutting, grinding or mixing.
[Introductio]
/ref>
Meat processing began as soon as people realized that cooking and salting helps to preserve fresh meat. It is not known when this took place; however, the process of salting and Drying (food), sun-drying was recorded in Ancient Egypt, while using ice and snow is credited to early Romans, and canning
Canning is a method of food preservation in which food is processed and sealed in an airtight container (jars like Mason jars, and steel and tin cans). Canning provides a shelf life that typically ranges from one to five years, although under ...
was developed by Nicolas Appert
Nicolas Appert (17 November 1749 – 1 June 1841) was a French confectioner and inventor who, in the early 19th century, invented airtight food preservation. Appert, known as the " father of food science", described his invention as a way "of c ...
who in 1810 received a prize for his invention from the French government. Medical health organizations advise people to limit processed meat consumption as it increases risk of some forms of cancer
Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...
, cardiovascular disease
Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina, heart attack), heart failure, hypertensive heart disease, rheumati ...
, and Alzheimer's disease
Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems wit ...
.
Definition
The American Institute for Cancer Research and World Cancer Research Fund define processed meat as "meat preserved by smoking, curing or salting, or addition of chemical preservatives".
The ''Encyclopedia of Meat Sciences'' defined processed meat as "any meat preserved by smoking, curing, or salting, or with the addition of chemical preservatives; examples include bacon, salami, sausages, hot dogs or processed deli, or luncheon meats".
Preservatives
Nitrate
Nitrate is a polyatomic ion with the chemical formula . salt (chemistry), Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are solubility, soluble in wa ...
and sodium nitrite found in processed meats can be converted by the human body into nitrosamines
Nitrosamines (or more formally ''N''-nitrosamines) are organic compounds produced by industrial processes. The chemical structure is , where R is usually an alkyl group. Nitrosamines have a nitroso group () that are "probable human carcinogens", ...
that can be carcinogenic, causing mutation in the colorectal cell line, thereby causing tumorigenesis
Carcinogenesis, also called oncogenesis or tumorigenesis, is the formation of a cancer, whereby normal cells are transformed into cancer cells. The process is characterized by changes at the cellular, genetic, and epigenetic levels and abn ...
and eventually leading to cancer. Processed meat is more carcinogenic compared to unprocessed red meat because of the abundance of potent nitrosyl-heme molecules that form N-nitroso compounds.
A principal concern about sodium nitrite is Nitrosation/ nitrosylation, the formation of carcinogenic nitroso-compounds in meats containing sodium nitrite or potassium nitrate, especially nitrosyl-haem ( nitrosyl heme). In addition to nitrosyl-haem, carcinogenic nitrosamines
Nitrosamines (or more formally ''N''-nitrosamines) are organic compounds produced by industrial processes. The chemical structure is , where R is usually an alkyl group. Nitrosamines have a nitroso group () that are "probable human carcinogens", ...
can be formed from the reaction of nitrite
The nitrite polyatomic ion, ion has the chemical formula . Nitrite (mostly sodium nitrite) is widely used throughout chemical and pharmaceutical industries. The nitrite anion is a pervasive intermediate in the nitrogen cycle in nature. The name ...
with secondary amines under acidic conditions (such as occurs in the human stomach) as well as during the curing process used to preserve meats.
Nitrate
Nitrate is a polyatomic ion with the chemical formula . salt (chemistry), Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are solubility, soluble in wa ...
and nitrite are consumed from plant foods as well as animal foods, with 80% of a typical person's nitrate consumption coming from vegetables, especially leafy and root vegetable
Root vegetables are underground plant parts eaten by humans or animals as food. In agricultural and culinary terminology, the term applies to true roots, such as taproots and root tubers, as well as non-roots such as bulbs, corms, rhizomes, and ...
s such as spinach
Spinach (''Spinacia oleracea'') is a leafy green flowering plant native to Central Asia, Central and Western Asia. It is of the order Caryophyllales, family Amaranthaceae, subfamily Chenopodioideae. Its leaves are a common vegetable consumed eit ...
and beets. Some nitrate is converted to nitrite in the human body. Nitrate and nitrite are classified as generally recognized as safe
Generally recognized as safe (GRAS) is a United States Food and Drug Administration (FDA) designation that a chemical or substance added to food is considered safe by experts under the conditions of its intended use. An ingredient with a GRAS d ...
(GRAS) by the U.S. Food and Drug Administration, and are not ''directly'' carcinogenic. Yet, when nitrate or nitrite interact with certain components in meat, such as heme iron, amines, and amides, they can form nitroso compounds, which may contribute to the association between consumption of processed meats and higher incidence of colorectal cancer.
Health effects
The International Agency for Research on Cancer
The International Agency for Research on Cancer (IARC; ) is an intergovernmental agency forming part of the World Health Organization of the United Nations.
Its role is to conduct and coordinate research into the causes of cancer. It also cance ...
(IARC) at the World Health Organization
The World Health Organization (WHO) is a list of specialized agencies of the United Nations, specialized agency of the United Nations which coordinates responses to international public health issues and emergencies. It is headquartered in Gen ...
(WHO) classifies processed meat as Group 1 (carcinogenic to humans), because the IARC has found sufficient evidence that consumption of processed meat by humans causes colorectal cancer
Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the Colon (anatomy), colon or rectum (parts of the large intestine). Signs and symptoms may include Lower gastrointestinal ...
.
A 2016 report by the American Institute for Cancer Research and the World Cancer Research Fund found that processed meat consumption also increases the risk of stomach cancer
Stomach cancer, also known as gastric cancer, is a malignant tumor of the stomach. It is a cancer that develops in the Gastric mucosa, lining of the stomach. Most cases of stomach cancers are gastric carcinomas, which can be divided into a numb ...
.
In 2020, the American Cancer Society
The American Cancer Society (ACS) is a nationwide non-profit organization dedicated to eliminating cancer. The ACS publishes the journals ''Cancer'', '' CA: A Cancer Journal for Clinicians'' and '' Cancer Cytopathology''.
History
The society w ...
stated that "it is not known if there is a safe level of consumption for either red or processed meats. In the absence of such knowledge, while recognizing that the amount of increased risk isn't certain, the ACS recommends choosing protein foods such as fish, poultry, and beans more often than red meat, and for people who eat processed meat products to do so sparingly, if at all."
Reviews of epidemiological studies have also found that processed meat consumption is associated with an increased risk of Alzheimer's disease
Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems wit ...
, cardiovascular disease
Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina, heart attack), heart failure, hypertensive heart disease, rheumati ...
, gastric cancer
Stomach cancer, also known as gastric cancer, is a malignant tumor of the stomach. It is a cancer that develops in the lining of the stomach. Most cases of stomach cancers are gastric carcinomas, which can be divided into a number of subtypes ...
, oral cancer
Oral cancer, also known as oral cavity cancer, tongue cancer or mouth cancer, is a cancer of the lining of the lips, mouth, or upper throat. In the mouth, it most commonly starts as a painless red or white patch, that thickens, gets ulcerated ...
, stroke
Stroke is a medical condition in which poor cerebral circulation, blood flow to a part of the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemor ...
, and type-2 diabetes.
A systematic review and meta-analysis
Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, th ...
of 148 published articles was carried out on studies of the consumption of red meat and processed meat in relation to cancer incidence. Processed meat consumption was significantly correlated with a 6% greater risk of breast cancer, an 18% greater risk of colorectal cancer, a 21% greater risk of colon cancer, a 22% greater risk of rectal cancer and a 12% greater risk of lung cancer[
]
References
Further reading
* Horowitz, Roger. ''Putting Meat on the American Table. Taste, Technology, Transformation''. Johns Hopkins University Press, 2005.
External links
Meat processing technology for small- to medium-scale producers
Gunter Heinz, Peter Hautzinger, Food and Agriculture Organization of the United Nations (FAO) Regional Office for Asia and the Pacific (RAP), Bangkok, 2007,
*{{Cite book, title = Processed Meats, url = https://books.google.com/books?id=XcPrCAAAQBAJ, publisher = Springer Science & Business Media, date = 2012-12-06, isbn = 9789401096928, first1 = A. M., last1 = Pearson, first2 = F. W., last2 = TauberIntroductio
Meat
IARC Group 1 carcinogens