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thumb|300px|Varieties of meatMeat is
animal flesh that is used as food.
[Lawrie, 1.] Most often, this means the
skeletal muscle and associated
fat, but it may also describe other edible tissues such as
organs,
livers,
skin,
brains,
bone marrow,
kidneys, or
lungs.
The word
meat is also used by the
meat packing industry in a more restrictive sense—the
flesh of
mammalian species (pigs, cattle, lambs, etc.) raised and prepared for human consumption, to the exclusion of
fish and
poultry.
Etymology
The word
meat comes from the
Old English word
mete, which referred to food in general. The term is related to
mad in
Danish,
mat in
Swedish and
Norwegian, and
matur in
Icelandic, which also mean 'food'. The word "mete" also exists in
Old Frisian (and to a lesser extent, modern
West Frisian) to denote important food, differentiating it from "swiets" (sweets) and "dierfied" (animal feed).
One definition that refers to meat as not including fish developed over the past few hundred years and has religious influences. The distinction between fish and "meat" is codified by the Jewish dietary law of
kashrut, regarding the mixing of milk and meat, which does not forbid the mixing of milk and fish. Modern Jewish legal practice (
halakha) on
kashrut classifies the flesh of both mammals and birds as "meat"; fish are considered to be
parve, neither meat nor a dairy food. The Catholic dietary restriction on "meat" on Fridays also does not apply to the cooking and eating of fish.
The Latin word
carō "meat" (also the root of 'carnal', referring to the 'pleasures of the flesh') is often a
euphemism for sexual pleasure, effected from the function performed by fleshy organs. Thus 'meat' may refer to the human body in a sensual, or sexual, connotation. A
meat market, in addition to simply denoting a
market where meat is sold, also refers to a place or situation where humans are treated or viewed as
commodities, especially a place known as one where a sexual partner may be found.
"Meat" may also be used to refer to humans humorously or indifferently. In military slang, "meat shield" refers to soldiers sent towards an enemy to draw fire away from another unit.
History
Meat constituted a substantial proportion of even the earliest humans' diet,
paleontological evidence suggests.
[Lawrie, 2.] Early
hunter-gatherers depended on the organized hunting of large animals such as
bison and
deer.
The
domestication of animals, of which we have evidence dating back to the end of the
last glacial period (c. 10,000 years
BP),
allowed the systematic production of meat and the
breeding of animals with a view to improving meat production.
The animals which are now the principal sources of meat were domesticated in conjunction with the development of early civilizations:
- Sheep, originating from western Asia, were domesticated with the help of dogs prior to the establishment of settled agriculture, likely as early as the eighth millennium BC.
[Lawrie, 3.] Several breeds of sheep were established in ancient Mesopotamia and Egypt by 3500–3000 BC.
- Cattle were domesticated in Mesopotamia after settled agriculture was established about 5000 BC,
[Lawrie, 5.] and several breeds were established by 2500 BC.[Lawrie, 6.] Modern domesticated cattle fall into the groups Bos taurus (European cattle) and Bos indicus (zebu), both descended from the now-extinct Aurochs.[Lawrie, 7.]
- Domestic pigs, which are descended from wild boars, are known to have existed about 2500 BC in modern-day Hungary and in Troy; earlier pottery from Jericho and Egypt depicts wild pigs.
[Lawrie, 8.] Pork sausages and hams were of great commercial importance in Greco-Roman times.[Lawrie, 9.]
Modern agriculture employs a number of techniques, such as
progeny testing, to make animals
evolve rapidly towards having the qualities desired by meat producers.
[Lawrie, 10.] For instance, in the wake of well-publicised health concerns associated with
saturated fats in the 1980s, the fat content of
UK beef, pork and lamb fell from 20–26 percent to 4–8 percent within a few decades, both due to selective breeding for leanness and changed methods of
butchery.
Methods of
genetic engineering aimed at improving the meat production qualities of animals are now also becoming available.
[Lawrie, 14.]Even though it is a very old industry, meat production continues to be shaped strongly by the rapidly evolving demands of customers. The trend towards selling meat in pre-packaged cuts has increased the demand for larger breeds of cattle, which are better suited to producing such cuts.
[Lawrie, 11.] Ever more animals not previously exploited for their meat are now being farmed, especially the more agile and mobile species, whose muscles tend to be developed better than those of cattle, sheep or pigs.
Examples include the various
antelope species, the
zebra,
water buffalo and
camel,
[Lawrie, 11 et seq.] as well as non-mammals such as the
crocodile,
emu and
ostrich.
[Lawrie, 13.] Another important trend in contemporary meat production is
organic farming which, while providing no
organoleptic benefit to meat so produced,
[Lawrie, 11, citing Ollson, V., Andersson, I., Ranson, K., Lundström, K. (2003) Meat Sci. 64, 287 and noting also that organically reared pigs "compare unfavourably" with conventionally reared ones "in some respects."] meets an increasing demand for
numerous reasons.
Growth and development of meat animals
Agricultural science has identified several factors bearing on the growth and development of meat in animals.
Genetics
{| class="wikitable" style="float:right;"|-! Trait! Heritability
[Table adapted from Lawrie, 17.]|-| Reproductive efficiency| 2–10%|-| Meat quality| 15–30%|-| Growth| 20–40%|-| Muscle/fat ratio| 40–60%|}Several economically important traits in meat animals are heritable to some degree (see the table to the right) and can thus be selected for by
breeding. In cattle, certain growth features are controlled by
recessive genes which have not so far been controlled, complicating breeding.
[Lawrie, 18.] One such trait is
dwarfism; another is the
doppelender or "
double muscling" condition, which causes
muscle hypertrophy and thereby increases the animal's commercial value.
continues to reveal the genetic mechanisms that control numerous aspects of the
endocrine system and, through it, meat growth and quality.
[Lawrie, 19.]Genetic engineering techniques can shorten breeding programmes significantly because they allow for the identification and isolation of
genes coding for desired traits, and for the reincorporation of these genes into the animal
genome.
[Lawrie, 21.] To enable such manipulation, research is ongoing () to
map the entire genome of sheep, cattle and pigs.
Some research has already seen commercial application. For instance, a
recombinant bacterium has been developed which improves the digestion of grass in the
rumen of cattle, and some specific features of muscle fibres have been genetically altered.
Experimental
reproductive cloning of commercially important meat animals such as sheep, pig or cattle has been successful. The multiple asexual reproduction of animals bearing desirable traits can thus be anticipated,
[Lawrie, 22.] although this is not yet practical on a commercial scale.
Environment
Heat regulation in livestock is of great economic significance, because mammals attempt to maintain a constant optimal body temperature. Low temperatures tend to prolong animal development and high temperatures tend to retard it.
Depending on their size, body shape and insulation through tissue and fur, some animals have a relatively narrow zone of temperature tolerance and others (e.g. cattle) a broad one.
[Lawrie, 23.] Static
magnetic fields, for reasons still unknown, also retard animal development.
Nutrition
The quality and quantity of usable meat depends on the animal's
plane of nutrition, i.e., whether it is over- or underfed. Scientists disagree, however, about how exactly the plane of nutrition influences
carcase composition.
[Lawrie, 25.]The composition of the diet, especially the amount of
protein provided, is also an important factor regulating animal growth.
[Lawrie, 26.] Ruminants, which may digest
cellulose, are better adapted to poor-quality diets, but their ruminal microorganisms degrade high-quality protein if supplied in excess.
[Lawrie, 27.] Because producing high-quality protein animal feed is expensive (see also
Environmental impact below), several techniques are employed or experimented with to ensure maximum utilization of protein. These include the treatment of feed with
formalin to protect
amino acids during their passage through the
rumen, the recycling of
manure by feeding it back to cattle mixed with feed concentrates, or the partial conversion of
petroleum hydrocarbons to protein through microbial action.
In plant feed, environmental factors influence the availability of crucial
nutrients or
micronutrients, a lack or excess of which can cause a great many ailments.
[Lawrie, 29.] In Australia, for instance, where the soil contains limited
phosphate, cattle are being fed additional phosphate to increase the efficiency of beef production.
[Lawrie, 28.] Also in Australia, cattle and sheep in certain areas were often found losing their appetite and dying in the midst of rich pasture; this was at length found to be a result of
cobalt deficiency in the soil.
Plant
toxins are also a risk to grazing animals; for instance,
fluoracetate, found in some African and Australian plants, kills by disrupting the
cellular metabolism.
Certain man-made
pollutants such as
methylmercury and some
pesticide residues present a particular hazard due to their tendency to
bioaccumulate in meat, potentially poisoning consumers.
[Lawrie, 30.]
Human intervention
Meat producers may seek to improve the
fertility of female animals through the administration of
gonadotrophic or
ovulation-inducing
hormones.
[Lawrie, 31.] In pig production,
sow infertility is a common problem, possibly due to excessive fatness.
[Lawrie, 32.] No methods currently exist to augment the fertility of male animals.
is now routinely used to produce animals of the best possible genetic quality, and the efficiency of this method is improved through the administration of hormones that synchronize the ovulation cycles within groups of females.
[Lawrie, 33.]Growth hormones, particularly
anabolic agents such as
steroids, are used in some countries to accelerate muscle growth in animals.
This practice has given rise to the
beef hormone controversy, an international trade dispute. It may also decrease the tenderness of meat, although research on this is inconclusive,
[Lawrie, 35.] and have other effects on the composition of the muscle flesh.
[Lawrie, 36 et seq.] Where
castration is used to improve control over male animals, its side effects are also counteracted by the administration of hormones.
may be administered to animals to counteract stress factors and increase weight gain.
[Lawrie, 39.] The feeding of
antibiotics to certain animals has been shown to improve growth rates also.
This practice is particularly prevalent in the USA, but has been banned in the
EU, partly because it causes
antibiotic resistance in
pathogenic microorganisms.
Biochemical composition
Numerous aspects of the biochemical composition of meat vary in complex ways depending on the species, breed, sex, age, plane of nutrition, training and exercise of the animal, as well as on the anatomical location of the musculature involved.
[Lawrie, 94–126.] Even between animals of the same litter and sex there are considerable differences in such parameters as the percentage of intramuscular fat.
[Lawrie, 126.]
Main constituents
Adult mammalian
muscle flesh consists of roughly 75 percent water, 19 percent
protein, 2.5 percent intramuscular
fat, 1.2 percent
carbohydrates and 2.3 percent other soluble non-protein substances. These include
nitrogenous compounds, such as
amino acids, and inorganic substances such as minerals.
[Lawrie, 76.]Muscle proteins are either soluble in water (
sarcoplasmic proteins, about 11.5 percent of total muscle mass) or in concentrated salt solutions (
myofibrillar proteins, about 5.5 percent of mass).
[Lawrie, 75.] There are several hundred sarcoplasmic proteins.
[Lawrie, 77.] Most of them – the glycolytic
enzymes – are involved in the
glycolytic pathway, i.e., the conversion of stored energy into muscle power.
[Lawrie, 78.] The two most abundant myofibrillar proteins,
myosin and
actin,
[Lawrie, 79.] are responsible for the muscle's overall structure. The remaining protein mass consists of
connective tissue (
collagen and
elastin) as well as
organelle tissue.
Fat in meat can be either
adipose tissue, used by the animal to store energy and consisting of "true fats" (
esters of
glycerol with
fatty acids),
[Lawrie, 82.] or intramuscular fat, which contains considerable quantities of
phospholipids and of
unsaponifiable constituents such as
cholesterol.
Red and white meat
Meat can be broadly classified as "red" or "white" depending on the concentration of
myoglobin in muscle fibre. When myoglobin is exposed to
oxygen, reddish oxymyoglobin develops, making myoglobin-rich meat appear red. The redness of meat depends on species, animal age, and fibre type:
Red meat contains more narrow muscle fibres that tend to operate over long periods without rest,
[Lawrie, 93.] while
white meat contains more broad fibres that tend to work in short fast bursts.
The meat of adult mammals such as
cows,
sheep,
goats, and
horses is generally considered red, while domestic
chicken and
turkey breast meat is generally considered white.
Production
Meat is produced by killing the animal in question and cutting the desired flesh out of it. These procedures are called
slaughter and
butchery, respectively.
Attesting to the long history of meat consumption in human civilizations,
ritual slaughter has become part of the practice of several religions. These rituals, as well as other pre-industrial meat production methods such as these used by
indigenous peoples, are not detailed here. This section will instead provide an overview of contemporary
industrialized meat production in dedicated
slaughterhouses from cattle, sheep and pigs.
Transport
Upon reaching a predetermined age or weight, livestock are transported
en masse from the farm to the slaughterhouse, a process called "
live export". Depending on its length and circumstances, this exerts stress and injuries on the animals, and some may die
en route. Apart from being arguably inhumane, unnecessary stress in transport may adversely affect the quality of the meat.
[Lawrie, 129.] In particular, the muscles of stressed animals are low in water and
glycogen, and their
pH fails to attain acidic values, all of which results in poor meat quality.
[Lawrie, 130.] Consequently, and also due to campaigning by
animal welfare groups, laws and industry practices in several countries tend to become more restrictive with respect to the duration and other circumstances of livestock transports.
Slaughter
Animals are slaughtered by being first
stunned and then
exsanguinated (bled out). Death results from the one or the other procedure, depending on the methods employed. Stunning can be effected through
asphyxiating the animals with
carbon dioxide, shooting them with a
gun or a
captive bolt pistol, or shocking them with electric current.
[Lawrie, 134 et seq.] In most forms of
ritual slaughter, stunning is not allowed.
Draining as much blood as possible from the
carcase is necessary because blood causes the meat to have an unappealing appearance and is a very good breeding ground for microorganisms.
[Lawrie, 134.] The exsanguination is accomplished by severing the
carotid artery and the
jugular vein in cattle and sheep, and the
anterior vena cava in pigs.
[Lawrie, 137.]
Dressing and cutting
After exsanguination, the carcase is dressed, that is, the head, feet, hide (except hogs and some veal), excess fat,
viscera and
offal are removed, leaving only bones and edible muscle.
[Lawrie, 138.] Cattle and pig carcases, but not thoseof sheep, are then split in half along the mid ventral axis, and the carcase is cut into wholesale pieces.
The dressing and cutting sequence, long a province of manual labor, is progressively being fully automated.
Conditioning
Under hygienic conditions and without other treatment, meat can be stored at above its freezing point (–1.5 °C) for about six weeks without spoilage, during which time it undergoes an aging process that increases its tenderness and flavor.
[Lawrie, 141.]During the first day after death,
glycolysis continues until the accumulation of
lactic acid causes the
pH to reach about 5.5. The remaining
glycogen, about 18 g per kg, is believed to increase the water-holding capacity and tenderness of the flesh when cooked.
[Lawrie, 87.] Rigor mortis sets in a few hours after death as
ATP is used up, causing
actin and
myosin to combine into rigid
actomyosin and lowering the meat's water-holding capacity,
[Lawrie, 90.] causing it to lose water ("weep").
[Lawrie, 146.] In muscles that enter
rigor in a contracted position, actin and myosin filaments overlap and cross-bond, resulting in meat that is tough on cooking
[Lawrie, 144.] – hence again the need to prevent pre-slaughter stress in the animal.
Over time, the muscle proteins
denature in varying degree, with the exception of the
collagen and
elastin of
connective tissue,
[Lawrie, 142.] and
rigor mortis resolves. Because of these changes, the meat is tender and pliable when cooked just after death or after the resolution of
rigor, but tough when cooked during
rigor. As the muscle pigment
myoglobin denatures, its iron
oxidates, which may cause a brown discoloration near the surface of the meat.
Ongoing
proteolysis also contributes to conditioning.
Hypoxanthine, a breakdown product of ATP, contributes to the meat's flavor and odor, as do other products of the discomposition of muscle fat and protein.
[Lawrie, 155.]
Spoilage and preservation
The spoilage of meat occurs, if untreated, in a matter of hours or days and results in the meat becoming unappetizing, poisonous or infectious. Spoilage is caused by the practically unavoidable infection and subsequent
decomposition of meat by
bacteria and
fungi, which are borne by the animal itself, by the people handling the meat, and by their implements. Meat can be kept edible for a much longer time – though not indefinitely – if proper
hygiene is observed during production and processing, and if appropriate
food safety,
food preservation and
food storage procedures are applied. Without the application of
preservatives and stabilizers, the fats in meat may also begin to rapidly decompose after cooking or processing, leading to an objectionable taste known as
warmed over flavor.
Methods of preparation
thumb|A spit at a street fair in New York City's East Village.]Meat is prepared in many ways, as
steaks, in
stews,
fondue, or as
dried meat like beef jerky. It may be ground then formed into patties (as
hamburgers or croquettes), loaves, or
sausages, or used in loose form (as in "sloppy joe" or
Bolognese sauce). Some meat is cured, by
smoking,
pickling, preserving in
salt or
brine (see
salted meat and
curing). Other kinds of meat are
marinated and
barbecued, or simply boiled,
roasted, or
fried. Meat is generally eaten cooked, but there are many traditional recipes that call for raw beef, veal or fish (
tartare). Meat is often spiced or seasoned, as in most sausages. Meat dishes are usually described by their source (animal and part of body) and method of preparation.
Meat is a typical base for making
sandwiches. Popular varieties of sandwich meat include
ham,
pork,
salami and other sausages, and
beef, such as
steak,
roast beef,
corned beef,
pepperoni, and
pastrami. Meat can also be molded or pressed (common for products that include
offal, such as
haggis and
scrapple) and
canned.
Meat nutritional information
{| class="wikitable" style="float:right; margin-left:1em;"|+
Typical Meat Nutritional Content
from 110 grams (4 oz or .25 lb)|-! style="background:#aaf; text-align:center;"|
Source! style="background:#ddf; text-align:center;"|
calories! style="background:#ddf; text-align:center;"|
protein! style="background:#ddf; text-align:center;"|
carbs! style="background:#ddf; text-align:center;"|
fat|-! style="background:#ccf; text-align:left;"| fish| style="background:#fff; text-align:center;"| 110–140| style="background:#fff; text-align:center;"| 20–25 g| style="background:#fff; text-align:center;"| 0 g| style="background:#fff; text-align:center;"| 1–5 g|-! style="background:#ccf; text-align:left;"| chicken breast| style="background:#fff; text-align:center;"| 160| style="background:#fff; text-align:center;"| 28 g| style="background:#fff; text-align:center;"| 0 g| style="background:#fff; text-align:center;"| 7 g|-! style="background:#ccf; text-align:left;"| lamb| style="background:#fff; text-align:center;"| 250| style="background:#fff; text-align:center;"| 30 g| style="background:#fff; text-align:center;"| 0 g| style="background:#fff; text-align:center;"| 14 g|-! style="background:#ccf; text-align:left;"| steak (beef top round)| style="background:#fff; text-align:center;"| 210| style="background:#fff; text-align:center;"| 36 g| style="background:#fff; text-align:center;"| 0 g| style="background:#fff; text-align:center;"| 7 g|-! style="background:#ccf; text-align:left;"| steak (beef T-bone)| style="background:#fff; text-align:center;"| 450| style="background:#fff; text-align:center;"| 25 g| style="background:#fff; text-align:center;"| 0 g| style="background:#fff; text-align:center;"| 35 g|}
- Further information: Nutrition, Foodborne illness, Health concerns associated with red meat
All
muscle tissue is very high in
protein, containing all of the
essential amino acids, and in most cases is a good source of
zinc,
vitamin B12,
selenium,
phosphorus,
niacin,
vitamin B6,
iron and
riboflavin.
[http://www.beef.org/uDocs/whatyoumisswithoutmeat638.pdf]Several forms of meat are high in
vitamin K2, which is only otherwise known to be found in fermented foods, with
natto having the highest concentration
. Muscle tissue is very low in carbohydrates and does not contain dietary fiber.
The fat content of meat can vary widely depending on the
species and
breed of animal, the way in which the animal was raised, including what it was fed, the
anatomical part of the body, and the methods of butchering and cooking. Wild animals such as
deer are typically leaner than farm animals, leading those concerned about fat content to choose
game such as
venison. Decades of breeding meat animals for fatness is being reversed by consumer demand for meat with less fat.
Red meat, such as beef, pork, and lamb, contains many essential nutrients necessary for healthy growth and development in children. Nutrients in red meat include iron, zinc, vitamin B
12, and protein.
Most meats contain a full complement of the amino acids required for the human diet. Fruits and vegetables, by contrast, are usually lacking several essential amino acids contained in meat. It is for this reason that people who abstain from eating all meat need to plan their diet carefully to include sources of all the necessary amino acids (See Section
Issues of Meat for more details)
The table in this section compares the nutritional content of several types of meat. While each kind of meat has about the same content of protein and carbohydrates, there is a very wide range of fat content. It is the additional fat that contributes most to the calorie content of meat, and to concerns about dietary health.
Issues with meat consumption
thumb|250px|Processed meat in an American [1]]
Ethics
Ethical issues regarding the consumption of meat can include objections to the act of killing animals or the
agricultural practices surrounding the
production of meat. Reasons for objecting to the practice of killing animals for consumption may include
animal rights,
environmental ethics, religious doctrine, or an aversion to inflicting
pain or harm on other
living creatures. The religion of
Jainism has always opposed eating meat, and there are also many schools of
Buddhism and
Hinduism that condemn the eating of meat. Some people, while not
vegetarians, refuse to eat the flesh of certain animals, such as cats, dogs, horses, or rabbits, due to cultural or religious
taboo. In some cases, specific meats (especially from pigs and cows) are forbidden within religious traditions. Some people eat only the flesh of animals which they believe have not been mistreated, and abstain from the meat of animals reared in
factory farms or from particular products such as
foie gras and
veal.
Health
- See Articles: Vegetarianism and Vegan
Consumption of large quantities of meat, like overconsumption of any caloric food, has certain adverse effects
which can include:
obesity,
heart disease, and
constipation . The common misconception of
"I can't eat unless there is meat" is largely due to cultural attitudes and how one is raised to think about food
[ U.S. government diet recommendations]. In recent years, health concerns have been raised about the consumption of meat increasing the risk of cancer.
In particular, red meat and processed meat were found to be associated with higher risk of cancers of the
lung, esophagus, liver, and
colon, among others, although also a reduced risk for some minor type of cancers.
Another study found an increase risk of pancreatic cancer for red meat and pork.
That study also suggests that fat and saturated fat are not likely contributors to pancreatic cancer. Animal fat, particularly from ruminants, tends to have a higher percentage of
saturated fat vs. monounsaturated and polyunsaturated fat when compared to vegetable fats, with the exception of some tropical plant fats;
consumption of which has been correlated with various health problems. The saturated fat found in meat has been associated with significantly raised risks of
colon cancer,
although evidence suggests that risks of prostate cancer are unrelated to animal fat consumption.
[ Fat and meat intake and prostate cancer risk: The multiethnic cohort study] USDA claims (see
Dietary Guidelines for Americans) that consumption of meat as a source of
protein in the human diet is crucial
[Lawrie, 26.] , have been resoundingly contradicted by recent studies.
[ Rejecting meat 'keeps weight low', BBC News, March 14, 2006.][ Position of the American Dietetic Association and Dietitians of Canada: Vegetarian diets, Journal of the American Dietetic Association, American Dietetic Association and Dietitians of Canada, 2003, vol 103, issue 6, pp. 748–65. doi 10.1053/jada.2003.50142.][Maggie Fox, Meat raises lung cancer risk, too, study finds, Reuters, December 10, 2007; A Prospective Study of Red and Processed Meat Intake in Relation to Cancer Risk, PLoS Medicine. April 21, 2008.]The correlation of meat consumption to increased risk of
heart disease is controversial. Some studies fail to find a link between red meat consumption and heart disease
[http://circ.ahajournals.org/cgi/content/abstract/CIRCULATIONAHA.109.924977v1] (although the same study found statistically significant correlation between the consumption of processed meat and cancer), while another study, a survey ,conducted in 1960, of 25,153 California Seventh-Day Adventists, found that the risk of heart disease is three times greater for 45-64 year old men who eat meat daily, versus those who did not eat meat.
[ Meat consumption and fatal ischemic heart disease. Prev Med. 1984] - PubMed Result]. In another study
[ major Harvard University study] in 2010 involving over one million people who ate meat found that only processed meat had an adverse risk in relation to coronary heart disease. The study suggests that eating 50g (less than 2oz) of processed meat per day increases risk of coronary heart disease by 42%, and diabetes by 19%. Equivalent levels of fat, including saturated fats, in unprocessed meat (even when eating twice as much per day) did not show any deleterious effects, leading the researchers to suggest that "differences in salt and preservatives, rather than fats, might explain the higher risk of heart disease and diabetes seen with processed meats, but not with unprocessed red meats."
A 2009 study by the
National Cancer Institute revealed a correlation between the consumption of red meat and increased mortality from cancer and cardiovascular diseases.
This study has been criticized for using an improperly validated food frequency questionnaire,
which has been shown to have low levels of accuracy
In response to changing prices as well as health concerns about saturated fat and cholesterol, consumers have altered their consumption of various meats.
A USDA report points out that consumption of
beef in the
United States between 1970–1974 and 1990–1994 dropped by 21%, while consumption of
chicken increased by 90%. During the same period of time, the price of chicken dropped by 14% relative to the price of beef. In 1995 and 1996, beef consumption increased due to higher supplies and lower prices.
Cooking
Meat, like any food, can also transmit certain
diseases, but complete cooking and avoiding recontamination reduces this possibility
.
Several studies published since 1990 indicate that cooking muscle meat creates
heterocyclic amines (HCAs), which are thought to increase cancer risk in humans. Researchers at the National Cancer Institute published results of a study which found that human subjects who ate beef rare or medium-rare had less than one third the risk of stomach cancer than those who ate beef medium-well or well-done.
While eating muscle meat raw may be the only way to avoid HCAs fully, the
National Cancer Institute states that cooking meat below creates "negligible amounts" of HCAs. Also,
microwaving meat before cooking may reduce HCAs by 90%.
, present in processed and cooked foods, have been noted as being carcinogenic, being linked to colon cancer. Also, toxic compounds called PAHs, or Polycyclic aromatic hydrocarbons, present in processed, smoked and cooked foods, are known to be carcinogenic.
In vitro and imitation
- Main articles: Imitation meat, In vitro meat
Various forms of
imitation meat have been created to satisfy people wishing to reduce or eliminate meat consumption for health, environmental, or ethical considerations, but who still wish to taste the flavor and texture of meat. They are typically some form of processed
soybean, (
tofu,
tempeh), but they can also be based on
wheat gluten or even fungus (
quorn).
In vitro meat, also known as
cultured meat, is animal flesh that has never been part of a complete, living animal. Several research projects are currently experimentally growing in vitro meat, but no meat has yet been produced for public consumption.
[{{cite news] | title = In Search of a Test-Tube Hamburger
| publisher = TIME
| date = 2008-04-23
| url = http://www.time.com/time/health/article/0,8599,1734630,00.html?imw=Y
| accessdate = 2009-04-30 }}
The goal is to grow fully developed muscle organs, but the first generation will most likely be minced meat products.
Environmental impact
The UN Food and Agriculture Organization (FAO) has estimated that direct emissions from meat production account for about
18% of the world's total greenhouse gas emissions. The FAO figure accounts for the entire meat production cycle -
clearing forested land, making and transporting
fertiliser, burning
fossil fuels in
agricultural machinery, and the front and rear end emissions of cattle and sheep.
In tracking food animal production from the feed through to the dinner table, the inefficiencies of grain fed meat,
milk and
egg production range from a 4:1 energy input to protein output ratio up to 54:1, in the opinion of Roger Segelken.
See also
References
Footnotes
External links
*MeatVleisلحمCarneܒܣܪܐSo'oAychaƏtМясаMesoМесоCarnMasoCigKødFleischAtsįʼCarneViandoگوشتViandeFeillFeòilCarne肉고기मांसMesoKarnoDagingNiqipiaqKjötCarneבשרDagingInyamaNyamaVyannGoştCaroGaļaMėsaCarnaHúsഇറച്ചിلحمهDagingМахVlees食肉KjøttKjøttChaiMięsoCarneCarneAychaМясоЭтCarniMeatInyamaMäsoMesoHilibМесоMesoLihaKöttKarneஇறைச்சிГӯштEtМ’ясоThịtKarneפלייש肉類Mēsa肉类食物
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