Cookbook:Meat

Meat
Category	Basic foodstuffs

Cookbook | Recipes | Ingredients | Equipment | Techniques | Cookbook Disambiguation Pages | Ingredients | Basic foodstuffs

Meat refers most broadly to the edible portions of animals, and usually to mammals and birds, though some reptiles and amphibians are also eaten as meat. It is considered culinarily distinct from seafood, though they share several key characteristics and may be used similarly.

Characteristics

Definition

The precise definition of the term "meat" is not fully agreed-upon, with some considering only the muscular tissue as meat while others include all the edible tissue (such as organs) under the meat umbrella. Some may use the term "organ meats" or "variety meats" to clearly differentiate these from the skeletal muscle of the animal carcass, though some organ meats do still contain muscle, albeit of a different type. Some sources may even limit the term "meat" to exclude poultry, but this chapter does not do so.

Composition

As with all living or recently-alive tissue, the bulk of meat is water. After this, the most abundant component is protein of various types, such as structural, metabolic, regulatory, etc. Two classes of protein based on their overall structure are globular proteins and fibrous proteins. Another classification scheme divides meat proteins into contractile/myofibrillar (e.g. actin and myosin), soluble/sarcoplasmic (e.g. myoglobin, enzymes), and stromal/connective (e.g. collagen and elastin). The exact types of protein will vary according to the animal and tissue type.

Another major component of meat is lipids or fat. This can be divided into two general types, saturated and unsaturated, with the former being generally more prevalent in meat than the latter. The overall fat content, type, and characteristics of meat hinges on a variety of factors, including species, sex, breed, age, diet/lifestyle, tissue type, and location on the animal. For example, poultry fat is relatively soft among animal fats, lamb fat is strongly flavored, beef shoulder is fattier than the leg, etc. Additionally, grass-fed animals produce fat with both a stronger taste and higher levels of Omega-3 fatty acids than do grain-fed animals. Fat contributes significantly to the flavor of meat, and it carries several fat-soluble vitamins. Ultimately, fat in meat will become rancid and unpalatable, with unsaturated fats doing so more rapidly than saturated fats. This is a reason that beef keeps for longer than poultry—the former has more stable fat.

There is very little carbohydrate in meat, and most that remains is quickly used up after death of the animal. The tiny amount left over, however, contributes to Maillard browning.

Tissue types

An animal carcass contains several different types of tissue, which can be classified differently, depending on the authority. For our purposes, we will be focusing on several tissues that are attested in various sources: muscle, fatty tissue, connective tissue, epithelial, nervous, and glandular. These different tissues are distributed heterogeneously throughout the animal, and the tissues in a given meat will contribute to its specific characteristics.

Muscle

Muscular tissue is some of the most abundant and prized tissue in animal carcasses. The basic structural unit of muscle tissue is the muscle cell or "muscle fiber". These cells are very long and thin, and they are packed full of myofibrils, which contain the contractile proteins (actin and myosin) that make muscles contract and relax. Younger animals have cells with fewer myofibrils; as an animal ages and/or its muscles get stronger, the cells fill with more myofibrils. In general, the more myofibrils packed into a muscle, the stronger and tougher it is. Each muscle cell is wrapped in the endomysium, which is a fibrous connective tissue that supports the cell, nerves, and capillaries. Muscle cells are bundled together into groups called fascicles, and these fascicles are wrapped in another connective tissue layer called the perimysium. Multiple fascicles, too, are bundled together and wrapped in yet another connective tissue layer, this time called the epimysium, which binds muscles together and to each other. Distributed among the various bundles are nerves, blood vessels, fatty tissue, and connective tissue.

A beef flank steak—note the long, parallel fibers running left to right, which together make up the grain of the meat.

The direction in which the fibers run determines the grain of the meat—when a recipe instructs you to cut against or across the grain, it means to cut perpendicular to the direction the fibers are running. The grain can be anywhere from fine to coarse, with the former having smaller fibers making smaller bundles, and the latter having large fibers and bundles.

Technically speaking, there are three primary types of muscular tissue: skeletal, cardiac, and smooth. Skeletal muscle is the most abundant and is what some people think of first when it comes to meat—steaks, for example, are made of skeletal muscle. Skeletal muscles are attached to bone, and their contraction allows for movement of the body. The description of muscle tissue above classically applies to skeletal muscle. Cardiac muscle tissue is similar to skeletal in that it is striated, but it is found only in the heart and contracts involuntarily. Smooth muscle, on the other hand, is quite different from the other two. It lacks the same long fibers and striations, and it is typically found within various organ systems like the digestive, respiratory, circulatory, and other systems.

Fatty

Beef with a high degree of marbling

As the name implies, fatty or adipose tissue is that which stores fats in meat, either for energy or protection. These fatty deposits are distributed in various places throughout the animal, where they have different characteristics. Subcutaneous fat deposits are stored just beneath the skin (e.g. pork fatback). Deeper within the carcass, visceral fat surrounds internal organs, such as the kidneys, guts, and heart. Caul fat is a specific lacy network of fatty tissue in the abdomen of some animals. Fatty tissue specific to muscles includes the inter- and intra-muscular fats. Intermuscular or seam fat is located between whole muscle groups, while intramuscular fat is deposited within the muscle fibers. When this intramuscular fat is significantly and evenly speckled through the tissue, it is referred to as marbling, and it adds tenderness by disrupting the muscle tissue. Not all meat has intramuscular fat—poultry, for example, does not contain it.

When uncooked, fatty tissue is chewy and generally unpleasant. When cooked, however, the fat renders out of the tissue, contributing flavor and juiciness.

Connective

Another somewhat self-explanatory type of tissue is connective tissue, whose main job is holding together and supporting other varieties of tissue. Technically, fatty tissue falls into the connective tissue category, as do skin and bone. Connective tissues often contain a few major types of proteins: collagen, elastin, and reticulin. Elastin is yellow in color and is particularly tough, not breaking down during cooking—as such, tissues containing a lot of it may be completely removed. Collagen, on the other hand, starts off tough and strong but largely breaks down with slow, moist heat into gelatin. It is whitish in color and does not necessarily need to be removed, depending on the application.

These different proteins contribute to various types of connective tissue. For example, tendons and ligaments are largely composed of fibrous collagen, connecting muscle and bone to each other. Cartilage, of which there are a few kinds, is also largely collagenous and can be found across the carcass. Muscles that are frequently used or bear heavy loads often contain a large amount of collagen for support. Interestingly, collagens from older animals are tougher and harder to break down.

Other

Nervous tissue is that which comprises the brain and nerves of an animal, signaling to and regulating various systems across the body. It is edible and often eaten, though consuming this kind of tissue is avoided by some due to risk of prion disease. Epithelial tissue is typically found in organs like blood vessels, kidney, liver, and skin. Glandular tissues are found in certain organs. They are tender, highly perishable, and easy to overcook.

Texture

The major textural consideration for meat is its tenderness or toughness. For muscular meats, this fundamentally comes down to the base strength and development of the muscle fibers and the connective tissue, as well as how interrupted these are by fatty tissue and to what degree they are broken down. As previously alluded to, meat with more of both contractile proteins and structural connective tissues is tougher and more difficult to cut and chew. This is typically the case with older and more frequently-exercised muscles, such as those in the shoulders and legs of quadrepeds and the legs of poultry. The tenderloin of beef, for example, is on the back of the animal and infrequently used, which makes it extremely tender. A number of different technical methods have been developed to measure the tenderness of a piece of meat.

Color

When raw, muscular tissue ranges from pale pink to dark red in color; when cooked, the color becomes tan to brown. The ultimate color of the meat hinges on myoglobin, the red oxygen-binding pigmented compound in the muscle tissue, and meat with more myoglobin content has a more intense pigmentation when raw. But, the color of a given piece of meat also depends on what the myoglobin is bound to. When myoglobin is not bound to oxygen, it has a deep red to purple color; however, when myoglobin binds to oxygen, it develops a bright red color. After a long-enough exposure to oxygen, the myoglobin becomes oxidized and turns brown. Cooking also turns it brown. This brown color in raw meat is not necessarily an indication that the meat has spoiled, but it can sometimes indicate older meat, which may be more likely to be spoiled. Properly aged meat, for example, is browned but not spoiled. Sometimes, meat will be packed under carbon monoxide, since this also results in a bright red color.

Different varieties of meat are sometimes divided into categories based on overall color. For example, chicken is commonly understood as white meat while beef is classed as red meat. However, things can get tricky—for example, veal, which is simply young beef, may be classified as white meat and s very similar to chicken breast. As such, a more comprehensive portrait of meat color can be formed based on a combination of the animal species, age, type of tissue, and activity.

Simplistically, we can divide skeletal muscle tissue into two primary types: that which is exercised consistently and often versus that which is sporadic and functions in short bursts. The former is classed as "slow-twitch" or endurance muscle, and it has high oxygen and metabolic requirements, which leads to higher myoglobin and cytochrome content. Conversely, the sporadically active muscle tissue is classed as "fast twitch" and has a lower oxygen requirement and, therefore, less myoglobin. A classic example to illustrate this is in poultry—domestic chickens flap their wings infrequently but use their legs often and consistently, leading to lighter breast meat and darker thigh meat. Migratory birds, on the other hand, have darker breast tissue for flying long distances, ruminants have dark cheek muscles, and whales have nearly black flesh due to the oxygen stores needed during diving.

Another consideration regarding meat color is curing. Nitrites, for example, which are used in some cured meats, impart a heat-stable pinkish red color.

Flavor

A few things contribute to the overall flavor and aroma of meat. At its base, most meat doesn't have a particularly strong flavor profile. However, during cooking, several chemical reactions occur to produce flavorful compounds—these include the Maillard reaction between amino acids and sugars, Strecker degradation, and lipid degradation. Aging of meat also produces small, flavorful compounds as a result of enzymatic activity, and reheating cooked meat can result in an off-flavor due to lipid autooxidation. The ultimate flavor of meat depends on a variety of factors such as animal species, tissue type, animal age, animal sex, exercise level, fat content, diet, and meat aging. Red muscle fibers tend to be more flavorful than white, and fat confers a good deal of flavor to meat. Tougher meat also tends to be more flavorful.

Production

Handling

Pre-slaughter handling of the animals is important for two reasons. The first is ethical—stress and injuries are unpleasant and cause suffering to the animal. Additionally, stressful handling reduces the quality of the final meat. As a result, care should be taken to avoid various stressors such as overcrowding, temperature extremes, loud noises, excessive confinement, hunger, pain, harsh lighting, social changes, etc.

Stunning and slaughter

In many slaughterhouses, the animals are stunned prior to slaughter to immobilize them, reduce their stress, and facilitate post-slaughter processing. This is done in one of three ways: electrical, modified atmosphere, or physical. The first two are typically done for smaller animals (e.g. poultry), while physical stunning is used for larger animals (e.g. cattle). Electrical stunning is done in a salt-water bath and makes the animal unconscious. If the electric amperage is too high, broken bones and burst blood vessels can occur. In modified atmosphere stunning, oxygen is removed from a chamber housing the animals, which renders them unconscious without risk of physical contractions and their associated issues. In physical stunning, blunt-force is rapidly and precicely applied to a specific location on the animal's head to ensure loss of consciousness.

The goal during slaughter is usually to kill the animal as quickly and untraumatically as possible. Typically, the unconscious (if applicable) animal is restrained, and major blood vessels in the neck are severed so that the animal quickly bleeds out. Proper bleeding ensures death and reduces the risk of meat spoilage.

Scalding, plucking, and skinning

Certain animals, such as pigs and poultry, must be scalded in hot water to facilitate the removal of feathers or hair. With poultry, the scalding may be either "hard" or "soft". Hard scalding takes place at higher temperature and removes the yellow skin cuticle, while soft scalding takes place at cooler temperatures, thereby leaving the cuticle intact. Poultry is plucked either by hand (at small-scale) or by machine. The process is similar for hair removal in pigs, though a singeing step may also be included to remove fine hairs.

In some animals, such as beef and lamb, the hide is removed; in others, such as pork and poultry, the hide is left on. If the hide is excessively dirty, it may need to be cleaned to prevent contamination of the rest of the carcass.

Evisceration

Once the hide is taken care of, the carcass must be eviscerated. Here, the internal organs are separated from the bones and muscle and removed, a process that can be done by hand or by automated machine, depending on the animal and the processor. It's critical to leave the digestive tract intact when removing it, since contamination of the rest of the carcass with fecal matter requires that portion of carcass to be discarded. The removed organs may be inspected, and the edible ones may be retained for consumption.

Chilling

Because meat is highly perishable, prompt chilling is necessary to delay spoilage. This is done either through immersion in cold water or blasting with cold air. In immersion chilling, the first stage gradually brings the carcass to 45–55°F (7.2–10°C), while the second stage brings them to 33–35°F (0.6–1.7°C)—this two-step process is done to avoid cold-shortening (see below). Air-chilling, on the other hand, uses forced cold air in a chiller, and this method avoids excess water uptake by the carcass.

While chilling is important, cooling the carcass too rapidly can result in meat quality issues. If the carcass becomes too cold (below 60°F / 15.5°C) before rigor mortis (see below) is completed, a condition called cold-shortening occurs. Here, the muscle fibers supercontract and become very tough. Hanging the carcass can help reduce this effect by stretching out the muscle. The recommendation is for carcass temperature to fall below 40°F (4°C) within 4 hours for chicken, 8 for turkey, and 24 hours for larger livestock like beef or pork.

Post-slaughter changes

Even after death of the whole animal, the meat itself does not fully "die"—rather, it remains metabolically active for a period of time. Shortly after the animal's death, the cells continue generating energy, using up the remaining oxygen in the tissue. Once all the oxygen is consumed, muscle tissue switches to anaerobic metabolism using the remaining glycogen stores in the meat. As the glycogen is metabolized, lactic acid is formed as a byproduct and accumulates in the tissue, lowering its pH. This is beneficial for two main reasons. First, the increased acidity makes it harder (though not impossible) for microbes to grow, delaying the eventual spoilage of the meat. The acidity also tenderizes the meat by helping to denature its constituent proteins.

Once all the glycogen in the muscle tissue is used up, the tissue can no longer generate energy. At this point—usually within several hours after slaughter—the muscle fibers get locked together, and the meat enters rigor mortis, becoming very stiff and tough. Over time, the fibers are degraded by enzymes and acidity in the meat, and the tissue ultimately relaxes again. Both the time until onset of rigor mortis and the ultimate duration of the rigor depend on a few factors. For example, commercial chickens take 6–8 hours to resolve rigor; turkeys 8–10 hours; up to a day or more for beef. For optimal taste and texture, meat should neither be frozen nor cooked until rigor mortis has passed; doing so will result in tough, dry, and unpleasant meat. Cutting the meat while it is in rigor also causes textural issues.

If an animal is stressed or tired out too soon prior to slaughter, it will use up its muscular glycogen stores but clear any lactic acid while still alive. This results in lower glycogen content after death, less lactic acid buildup in the tissue post-mortem, and lower acidity, thereby reducing the tenderness and the meat's ultimate shelf life. It also runs out of energy and enters rigor mortis more quickly. This meat is especially dark in color due to the effects of the higher pH and thus called "dark-firm-dry" or DFD for short. On the other hand, high stress resulting in excessive acidity while the meat is too warm leads to "pale-soft-exudative" or PSE meat, which has a mushy texture. Note that DFD and PSE meats are not unsafe to eat; they may just have qualities that are less desirable to the diner.

Aging

Even after the completion of rigor mortis, muscle meat can still benefit from an aging process that ranges anywhere from days to weeks after slaughter. This process is intended to improve meat by rendering it more tender and flavorful. A good chunk of the aging process is the work of enzymes, which continue to break down various parts of the tissue for a long time after death. Proteolytic enzymes break down various proteins, including the contractile proteins and those in connective tissue. This both improves the tenderness and helps with moisture retention by reducing contraction of the meat during cooking. Amino acids coming from the breakdown of these proteins also help contribute to savory flavor in the meat. Similarly, carbohydrates are broken into glucose, any residual ATP is converted to savory IMP, and lipids are broken down into fatty acids, all of which contributes to flavor.

Enzymatic activity generally increases with temperature up to a point, after which they denature and lose their activity. The higher the temperature, the greater the activity. This activity can therefore continue during the first part of cooking, before the meat gets so hot that denaturation occurs. Such "aging" usually occurs in very large pieces of meat that are cooked slowly in the oven, such as large roasts, and these benefit from the changes in taste and texture.

Dry aged cuts of beef

Two primary types of aging exist: wet and dry. In wet aging, fresh meats are vacuum-packed and kept under refrigeration for varying amounts of time, depending on the meat. Often, wet aging simply takes place during the time it takes to bring the meat to market, especially for meats that are only aged for a few days. Dry aging, on the other hand, is a much more resource-intensive process. Here, large cuts of meat are hung up in cold storage with controlled humidity, temperature, and airflow such that the meat is exposed to air on all sides during the aging process. Over the course of dry aging, the meat loses a significant amount of moisture, which concentrates the flavor. During this time, the outer layers may dry out and grow mold, and this layer will need to be trimmed off and discarded. Typically, it is meats like beef and lamb that get dry aged, and these meats are expensive due to the yield loss and effort required. However, the quality may be considered better than that of wet-aged meat due to the flavor concentration.

Note that aged meat should never actually spoil. If it tastes spoiled, it likely is. Wet-aged meat may have an odor that dissipates after the packaging is removed and the meat is rinsed—if the odor persists, it may be spoiled. Different meats can age for different amounts of time. Beef, for example, can be aged for up to several weeks. Pork and chicken fat readily goes rancid and is not aged for more than a few days.

Special procedures

Religious regulations require that specific guidelines be followed to produce kosher and halal meat. Typically, trained religious personnel must say a prayer and perform the slaughter by quickly severing the neck with a very sharp blade. In many cases, stunning is not permitted before slaughter due to considerations of humaneness. Scalding may also be forbidden. For kosher meats, blood vessels and nerves must be fully removed from the meat, and the meat may ultimately need to be either salted or broiled for all blood to be considered removed. Salting reduces the shelf life due to increased oxidation.

Inspection and grading

Many regions require meat to be inspected at various points prior to sale. This inspection is an assessment of wholesomeness and safety for human consumption, but inspection does not necessarily guarantee its quality beyond that. Essentially, the animal must be free from disease and be processed in clean conditions.

In contrast to inspection, grading may not be mandatory, and it reflects meat quality beyond simple wholesomeness. The standards vary between jurisdictions based on what criteria are important to the consumer. Some characteristics considered during grading include texture, color, fat content, marbling, age, sustainability, and welfare. Some carcasses may also be yield graded, which indicates how much usable muscle meat there is per weight of carcass.

Fabrication

Once inspection and grading are completed, the carcass can be broken down into pieces, with differences based on the species. Large animals may be cut down the backbone into two sides, and smaller animals may be cut across the abdomen into saddles. From there, the carcass is divided into primals, which are very large cuts that are not often cooked and served on their own. Examples of primals include chuck/shoulder, loin, flank, etc. Primals are then fabricated into subprimals and individual portion sizes. The primals can be broken down in different ways to yield different portion cuts, and the types of cut available in a given region or cuisine will depend on common cooking styles. Note that the naming of cuts varies according to the animal and the individual. Depending on the cut and preparation style, the meat may need to be trimmed. This typically refers to removal of excess fatty and connective tissue (sometimes called silverskin) that would negatively affect the cooked product, but trimming off portions of meat to improve aesthetics is also done.

The various steps of fabrication can take place anywhere from slaughterhouse and packing plant to a retail butcher or the kitchen, depending on the specific operation. Smaller cuts may be vacuum packed out of the packing plant, which gives a slightly longer shelf life.

Selection and storage

When evaluating fresh meat, assess its appearance, texture, and odor. Generally speaking, fresh meat should not have any significant smell, and certainly not an unpleasant one. It should be firm and slightly moist but not slimy or sticky, and it should not have a greenish color. As mentioned above, browning is not necessarily an indication of spoilage. Avoid meat in leaking or damaged packages, store it in secondary containment, and keep it cold during transport.

As fresh meat is highly perishable, storing it in the refrigerator will help delay spoilage while maintaining its optimal qualities. Ideal refrigeration temperature is 30–35°F (–1–2°C), since the freezing point of meat is slightly below that of pure water. Vacuum-packed meat should be left in the packaging, if undamaged, until time of use. Meat that is no longer in vacuum packaging should ideally be wrapped in paper (not plastic wrap) to allow enough air circulation to discourage microbial growth without excessive drying. Store meat below other foods in the refrigerator to prevent contamination from any dripping. Once purchased, properly refrigerated meat can keep for up to several days, though well-sealed and vacuum-packed meats can last longer, and ground meat has an even shorter shelf life due to surface area. Organ meats have particularly short shelf life.

Along with microbial spoilage, meat can suffer from oxidation, which leads to unpleasant flavors. Saturated fats are less susceptible to oxidation, so beef keeps the longest in this respect. Salted meat is more susceptible to oxidation.

One way to significantly extend the shelf life of raw meat is to freeze it, which enables it to maintain quality for weeks to months and stay edible nearly indefinitely. One potential downside to freezing is negative textural impacts to the tissue. When you freeze meat, ice crystals can damage the cells, causing the meat to become somewhat mushy and to lose liquid when thawed and cooked. The more rapidly the meat freezes and the colder the storage temperature, the smaller the ice crystals and the less damage there is. Industrial freezers are the best for this purpose.

When meat stored in the freezer is exposed to air for a prolonged period, the ice crystals at the surface can evaporate, drying out the meat. Frozen meat is also susceptible to rancidity and off flavors from oxidation. These negative effects can be delayed by sealing frozen meat well in airtight packaging, but frozen meat will ultimately only maintain quality for up to several months. Fish and poultry have the shortest shelf life, followed by pork, lamb, and beef. Cooked meat generally has fewer negative textural effects when frozen than does raw meat.

Frozen meat typically needs to be thawed before cooking. If you have a lot of time to do so, the best way to thaw it is in the refrigerator (on a tray to catch drips). If you have less time, thaw the meat in cold running water. Never thaw under warmer water or at room temperature. The larger the cut, the longer it will take to thaw fully. Re-freezing after thawing will worsen the quality but not decrease the safety, provided it has not been too long. Some sources say that you can cook meat before it has fully thawed—however, know that not all cooking methods will allow the meat to safely and evenly cook the meat through without overcooking the outer regions.

Safety

Microbial contamination of meat generally comes from exposure to the environment or the contents of the gastrointestinal tract (e.g. feces) during processing. Even then, these microorganisms are usually limited to the surface of intact pieces of (muscle) meat. Grinding, pricking, or anything else that exposes the interior of a cut to the environment can introduce contamination to the inside. Larger carcasses may be treated with more care, limiting contamination. Meat that is sold "mechanically tenderized" may have the inside contaminated due to microscopic cuts, and it may not have this treatment noted on the packaging.

Certain microbes commonly contaminating meat can be particularly harmful to humans when ingested. These include Salmonella bacteria, Campylobacter bacteria, and virulent E. coli strains. Such microbes can be killed by sufficiently heating the meat, but toxins they produce when allowed to grow unchecked may not be destroyed by heating. Pork may be contaminated by Trichinella parasites, which are present specifically within the muscle tissue—pork that has been fed uncooked food, especially containing waste and rotten materials, is most susceptible to Trichinella contamination. Freezing pork for at least 20 days will kill any parasites, as will cooking it to 58°C (136.4°F).

One meat-borne illness that cannot be avoided by cooking is a prion disease often called "mad cow disease". The prions can be present in the nervous tissue and muscle of animals that have themselves been fed prion-contaminated meat. Because the prions are not adequately destroyed by cooking, meat contaminated with them will cause fatal disease after ingestion.

In general, proper storage, cooking, and cleaning will significantly reduce the risk of illness from microbial contamination. Wash all tools that contact raw meat with hot water and soap. Some meats may be irradiated to reduce the microbial load, but improper handling can still cause them to be re-contaminated later. Do not leave meats at room temperature to warm up, as this causes a higher risk of microbial growth.

Techniques

Tenderizing

Jaccard-style cutter

Tenderizing mallet

Beyond aging, there are a couple ways to tenderize tough cuts of meat. These techniques are classified as either mechanical or chemical. In mechanical tenderization, the meat fibers are physically damaged by force or by cutting. Pounding meat with a tenderizing hammer is a fairly straightforward way of doing so, and it also has the benefit of evening out the meat's thickness. A Jaccard cutter consists of a handle to which multiple sharp blades are attached, and these are pushed up and down through meat to tenderize it. Grinding and mincing take this to the extreme and create a wholly different, more delicate texture. When cutting muscle meat, slicing thinly against the grain tenderizes it by physically shortening the fibers, making it so you don't have to exert as much force when chewing to break them down.

Chemical tenderizers include enzymes that break down protein. Several of these are derived from plants such as papaya (papain), pineapple (bromelain), actinidin (kiwi), and fig (ficin). The main challenge with these is that they do not penetrate far into the intact meat in a reasonable time frame and can make the surface overly mushy if left for too long. Injecting them into the meat can help with even distribution of the enzymes. These enzymes will work differently at different pH.

The role of acids in meat tenderization is unclear. Some sources claim that acids tenderize meat by denaturing and degrading muscle fiber and collagen. Others, however, say that they do not actually tenderize the meat in themselves. Mark Gibson states that acidic (and alkaline) ingredients in marinades (and consequently lower or higher pH of the meat) increase tenderness and water retention in meat. Harold McGee also states that acidic conditions increase the water retention. On the other hand, Provost et al. state that at low and high pH, the proteins in meat lose some of their molecular charge, which reduces their water holding capacity. They also add that acidic denaturation of the protein can result in water loss from shrinkage and squeezing of the meat unless certain proteins are first degraded (e.g. enzymatically).

Marinating

Marinating meat is a controversial topic. In general, marinating is the process of soaking meat in a flavorful liquid before cooking in order to transfer the flavor to the meat. Tenderness is also sought through marination, and components of a marinade (e.g. sugar) can encourage browning. Note that marination is distinct from brining, which is discussed further below.

One of the main problems (and sources of contention) with marination is that the flavor does not actually penetrate very far (more than a few millimeters) into intact meat from the surface, even with longer marination times. Slicing the meat thinly or scoring it increases the surface area and therefore ensures that the marinade flavors more of the meat than if it were left intact. Injecting the marinade deep into the meat is also an option if you would like to keep the meat in larger pieces. Pricking the surface is not a particularly effective option. Commercial enterprises may use vacuum tumbling, where the meat marinates under vacuum—this results in greater absorption into the meat.

When marinating meat, it should be done in the refrigerator for safety. Since you want as much of the meat touching the marinade as possible, a good option is to combine the two in a plastic bag and squeeze out all the air. Otherwise, you would need to use a much larger volume of marinade to fully cover larger amounts of meat. Avoid reusing marinades—once the meat has contaminated it, it must be treated like raw meat in terms of safe handling, and it has a short shelf life in the fridge. Using the marinade to baste the same piece of meat it was used on is okay, as long as it is handled properly and cooked thoroughly.

The duration of marination will vary. Poultry, for example, absorbs flavors more quickly and requires a shorter marination (on the order of 2–4 hours) than do beef or pork. Smaller pieces of meat require less marination. Some sources caution against marinating for too long, varyingly citing both toughness and mushiness of the surface from acid and salt.

Salting and brining

In general, the application of salt to meat will disrupt its protein structure and cause muscle fibers to swell.

Salting or "dry brining" is essentially the process of coating a piece of meat in dry salt either right before or significantly before cooking. As a rule, ions from salt will migrate into the meat at a rate of about 1 inch (2.5 cm) per 24 hours. Some argue that allowing the meat to rest with the salt coating is ill-advised because it draws out moisture and makes it more challenging to achieve browning. Others, however, argue both that the moisture will be reabsorbed over time along with the salt and that any residual moisture can be patted off the surface right before cooking. Ground meat should not be presalted, since it will become rubbery.

Brining refers to the process of soaking meat in a high-salt solution. The high salt concentration in the brine forces the salt inside the meat's cells, which increases the meat's water-holding capacity. This increases the flavor and juiciness of the meat and protects it from drying out during cooking. The salt concentration in a brine depends on the meat used, but there is no fast rule. When experimenting, try a solution of anywhere from 1–10% salt (by weight). Generally speaking, the more salt in the brine, the less brining time is needed.

Tying and trussing

Untrussed (left) versus trussed (right) chicken

Some cooking methods call for the meat to be tied or trussed. Large pieces of meat may be tied or netted with twine to form a compact shape before cooking, which will allow for even shaping and cooking. Similarly, trussing poultry is the process of using twine to tie the legs and wings of poultry against the body to achieve the same purpose. For non-poultry tied roasts, the string is tied against the grain.

Larding and barding

Larded venison

Because fat prevents against moisture loss, lean cuts of meat can dry out during dry cooking. One way to avoid this is the application of fatty tissue to the cut. Barding refers simply to covering the surface of the meat with fatty tissue (often slices of pork fatback). In larding, strips of fatback are inserted into the meat with a special needle, mimicking natural marbling.

Basting

Basting is the process of spooning or piping cooking juices over the meat while it is cooking. It is commonly believed that this adds moisture to the meat, but this is not the case, since the juices will simply not soak back into the meat during cooking. What basting can do is help increase browning, reduce the rate of moisture loss, and prolong cooking in the oven by causing the temperature to drop periodically. Meat with a layer of fatty tissue on the top does not need to be basted.

Stuffing

Meat, especially poultry, is sometimes stuffed before cooking with mixtures that can include bread, grains, vegetables, fruits, and more. When stuffing meat, there are certain guidelines to keep in mind. Stuffing large items such as turkeys is both inefficient and risky—especially when cooking at lower temperatures—since it can take too long for the inside to heat up to a safe temperature, and bacteria can multiply to dangerous levels. Even if you are able to heat the stuffing to a safe temperature, this often results in the meat overcooking. Given this, stuffing small, single-serving items (e.g. cornish hens) is a better option. If you are stuffing meat, prepare and store the stuffing separately, chill it quickly, and keep it cold until just before stuffing and cooking. Do not store the uncooked stuffing inside the meat, and avoid letting the cooked stuffing cool for storage inside the meat—this can take too long. Stuff loosely, since it will likely expand during cooking. Cooking the meat and stuffing separately is a fine option; in this case, the stuffing may be called dressing.

Cooking

Cooking meat serves to kill pathogens, aid in breakdown and digestion, release moisture, and increase flavor/aroma.

When heat is applied to meat, the proteins eventually denature; globular proteins tend to expand, while fibrous proteins tend to shrink. After denaturation, the proteins can tangle and bind together in a process called coagulation. This coagulation eventually squeezes water from the meat, especially if it progresses before the connective tissue has had time to break down. Heat also causes fat to melt and render out of the fatty tissue, and collagen breaks down with time and moisture into gelatin.

It's important to note that denaturation happens at different points for the different proteins in meat, and even to different degrees within the same protein. Moreover, there is disagreement as to the specific temperatures. However, a general progression follows. Around 30–40°C (95–105°F), fibrous proteins begin to denature and shrink, becoming more opaque at the top of this range. Coagulation of myosin protein and contraction of collagen occurs somewhere between 50–60°C (122–160°F), squeezing water out of the tissue and making it seem juicier, and the collagen will also slowly break down to gelatin starting in this range if kept moist. At around 60–65°C (140–150°F), significant shrinkage and moisture loss occur, resulting in increasing dryness and chewiness. By 74–80°C (165–170°F), any microbes are destroyed, actin is coagulated, myoglobin is brown, proteins are tangled together, and much moisture is lost. Above 150°C (302°F), reactions produce browning. Note, of course, that long, slow, moist cooking of tougher cuts will still lead to moist-seeming and tender meat.

In quick, hot cooking methods, a cut of meat will not heat evenly—the outer regions will get hotter much more quickly than will the inner regions, so the results will not be even through the entire piece. Additionally, very large cuts (such as roasts) heat quite slowly in the center. The resulting slow, moist heating can help with collagen breakdown. Similar effects can be had with sous-vide cooking (see below).

Dry-heat

Cooking meat using dry heat methods is typically suitable for sufficiently tender cuts without excessive connective tissue. This style is generally meant to preserve the meat's natural juiciness, concentrate its flavor through evaporation, and increase its complexity of flavor and texture through browning.

Searing a beef steak in a skillet

Spit roasting

Searing refers to rapid surface browning of a piece of meat, often in a hot pan or over a hot grill. A persistent myth states that searing meat seals in its juices, but this is simply not accurate. It does, however, create color and flavorful browning at the surface. Searing can be done either at the beginning or the end of the cooking period, to slightly different effects.

Roasting or baking meat entails cooking it, uncovered, with dry heat from radiation or convection (hot air), usually in an oven or over a fire. When in an oven, the temperature is usually constant; however, spit-roasting involves spearing the meat on a spit and slowly turning it over a heating element. Meat roasting can be conducted at a wide range of temperatures, depending on the characteristics of the meat and the desired result. Low-temperature roasting takes place from about 250–325°F (120–165°C), and it has the advantage of producing tender, moist, evenly cooked meats. The larger the cut, the lower the temperature should be, since this prevents overcooking of the exterior before the interior cooks sufficiently. Of course, lower temperatures require longer cook times. Small cuts of meat may also not brown sufficiently during low-temperature roasting, so they can be started at a higher temperature or seared in a pan before/after roasting. Starting at high temperature can also be good for rendering a heavy outer fat layer, such as that found on ducks or geese. In contrast, high temperature roasting (375–500°F/190–260°C) may be used for the full cook time with small, tender items intended for serving rare, such as beef tenderloin, duck breast, or squab. Overcooking can happen easily at such high temperatures, so careful monitoring is key, but a crispy brown skin and rare interior can result. Oven-roasting the meat on a rack with the fatty portion up allows the rendering fat to drip down and baste the meat during cooking, without any pooling around the bottom. Rotating the item in the oven can help alleviate uneven cooking from hot spots. It is possible to roast very large (e.g. 40 lbs) cuts of tougher meat because the collagen at the interior begins to break down with the long cook time required for the larger cuts.

Broiling meat is to cook it underneath a heating element, while grilling refers to cooking the meat on a grate over a heat source. In both of these methods, the required temperature will depend on the thickness of the meat and the desired doneness, though thinner is generally better. Lower heat and longer time is required for items cooked medium to well, since you don't want the exterior to overcook while the interior cooks. On a grill, temperature can be controlled by the amount of coals or the size of the flame, and hotter/cooler regions can be established for different needs. Under a broiler, the rack can usually be moved closer to or farther from the heat source, and sometimes the power of the heat source can also be adjusted. For both of these cooking methods, excess fat or marinades can cause fiery flare-ups to occur. Grilled meats will have a smokier flavor than broiled meats due to drips from the meat burning on the heating element below, and they often have dark grill marks.

A few different ways to fry meat exist. In sautéing and stir-frying, small and thin pieces of tender meat are quickly cooked in a stovetop pan over high heat with a very small amount of fat. In these techniques, the pan must not be overloaded or allowed to get too cool, since this will cause excess moisture to accumulate. In pan-frying, the heat is slightly lower, there is more oil (usually about ½–⅔ up the side of the piece), and the cuts can be slightly thicker. As with other types of dry heat, thicker cuts generally require lower temperatures while thinner cuts require higher ones. In deep frying, the meat is fully submerged in the oil. This is most common for poultry, which is usually fried around 350–375°F (165–190°C).

In barbecuing meat, the cooking is done using gentle dry heat and smoke from a wood fire or coals. It is especially suitable for larger, tougher, fattier cuts of beef and pork, which become tender and moist with the long cooking. The simplest form of barbecuing is done in a covered pit or grill to hold in the heat and smoke. More modern barbecue cookers can have multiple compartments; one to hold the meat and one to heat the wood and produce smoke. In these cookers, temperatures in the food compartment stay around a gentle 200–325°F (93–163°C). Rubs and marinades are often used for flavoring, and periodic basting may be done as well. The smoky cooking will create a permanent pink layer ("smoke ring") beneath the surface of the meat, even when cooked through.

Moist heat

As the name implies, moist heat cooking methods for meat mean that the meat is cooked surrounded by moisture, usually at lower temperatures than are used in dry heat cooking. This allows meat to be cooked for longer without drying out entirely and burning, which is especially useful for tenderizing collagen-rich cuts. Moist heat methods are always used to produce well-done meat. Because moist heat does not produce browning, meats may be browned first to add color and flavor before cooking in moist heat.

Because the heat transfer is so efficient, steaming is a quick moist-cooking method, suitable for smaller, thinner pieces of tender meat. The meat should be steamed just until cooked through, since overcooking is still possible with this method—overcooked steamed meats will be tough and dry-seeming from over-shrinkage and moisture loss. Wrapping the meat in a leaf or parchment can help make the cooking gentler and more gradual. Lower-temperature steaming can also be done with water that is just simmering, in a specialty convection steamer, or at higher altitudes.

In poaching, tender meats are submerged in a cooking liquid and very gently cooked at low temperature (160–185°F / 71–85°C)—the water should not be bubbling at all. Poaching is reserved for already-tender cuts of meat such as tender young chicken, and the items are poached just until cooked through. Simmering is much like poaching, entailing full submersion in the liquid, but the temperature is higher—around 185–205°F (85–96°C). This is reserved for tougher cuts of meat that benefit from a long cooking time to tenderize the connective tissue. For example, tongue, tougher poultry, and brisket may all be simmered. Fatty birds are not commonly cooked by either poaching or simmering. The cooking liquid can be water or broth/stock, seasoned or flavored as desired.

Braising is technically a combination cooking method, since the meat is browned using hot, dry heat before liquid is added and the meat is gently simmered. If the meat is cut into smaller pieces for cooking, the same method is often called stewing. Braising can be done with anywhere from very little added liquid to full coverage of the meat, depending on the latent moisture present and the desired result. A slow simmer rather than a boil is key to gentle cooking and a tender result—this can be achieved on the stovetop or in a gentle oven. Oven temperatures from 250–300°F (120°–150°C) should maintain a simmer, with temperatures below 200°F (120°C) providing even gentler cooking. Braised meats should be cooled and served in the cooking liquid. Braising is especially suitable for tougher cuts that require long, slow, moist cooking. The finished product should be cooked through and fork-tender but not falling apart. Very gently braised meat may retain its original red color, since these conditions keep the myoglobin more intact.

Sous-vide cooking allows meat to be evenly brought to the precisely desired stage of doneness with a much lower risk of overcooking, and it can be used for both tougher and more tender cuts. Because sous-vide cooking does not brown the meat, it may be browned afterwards for flavor, color, and texture. Because the desired final temperature for some meats is in the food safety "danger zone" of 41–135°F (5–57°C), it's very important to ensure that these meats are not left in the sous-vide bath for durations that would allow the growth of significant harmful bacteria. Meat should never be at a danger zone temperature for more than 4 hours (i.e. from when it is removed from the fridge to when it is served). Particular attention to food safety and cleanliness must be taken when sous-vide cooking meat, and the meat should be finished and served immediately after the sous-vide process. Tougher meats may be cooked for longer at slightly higher temperatures (149–185°F / 65–90°C), which allows for breakdown of the connective tissue with sufficient time and at a lower risk of microbial development. Meats for cooking sous-vide should be cut into portion-sized pieces and vacuum-packed in a single layer to ensure rapid arrival at the necessary temperatures. Cuts that are about 1 inch (2.5 cm) thick should be cooked through after 1–2 hours.

Doneness

Doneness refers to the degree of heating that meat has attained. This can be assessed in a few different ways, and it's a good idea to judge based on a combination. Recommended timings can be a useful guide for planning and estimating doneness, but it is not very reliable (especially with larger/thicker cuts). Factors like actual temperature of the cooking environment, fat, bones, thickness, etc. can all change the time it takes to achieve a given doneness. Certain visual cues can provide guidance, such as the color of the meat and its juices when you cut into it. Red meats usually change from red to grey/brown, while white meats change from pink to off-white. However, note that color can be misleading—undercooked meat can look more done if the myoglobin browned when raw, and certain slow cooking methods can cause the meat to remain red/pink even when properly done. Taking the internal temperature of a piece of meat is a very accurate way to evaluate the doneness of sufficiently thick cuts. The thermometer should be inserted into the thickest part of the meat, and not touching fat or bone, since that will skew the reading. Another reliable method is the cook's sense of touch, which works well for smaller and thinner pieces of meat that are not large enough to accommodate a thermometer's probe. Pressing on the center of a section of lean meat and assessing the amount of resistance will tell you how well done it is. With poultry, the joints also become looser as doneness increases.

Doneness Reference for Meats

Doneness	Temperature	Characteristics
Raw		Very soft and jelly-like
Very rare (bleu)		Just warmed at the interior; similar feel to raw meat; little juice
Rare	120–130°F / 49–54°C	Soft and spongy, with very slight resistance and colored juices
Medium	up to 150°F / 65°C	Slightly firm and springy with pinkish juices
Well done	>150°F	Very firm and springy, sometimes stiff; fully denatured myoglobin

Note that the temperature of large pieces of meat will continue increasing for a short period after removal from the heat—this is called carryover cooking and should be taken into account when aiming for a specific level of doneness. Small roasts, for example, can increase in temperature by up to 5–10°F (3–6°C) after removal from the oven, and larger roasts by even more. Removing meat from the heat once it has already reached the desired doneness can result in overcooked meat.

Meat from different animals, from different cuts, and for different purposes are cooked to varying degrees of doneness. In general, poultry is cooked well-done, with the exception of certain game birds and duck/goose cuts, which may be cooked slightly below that point. Beef may be cooked anywhere from very rare to well-done, depending on the cooking style and diner preference. Tougher cuts are usually cooked to—or even past—well-done to achieve tenderness.

It's important to remember that the concept of doneness does not necessarily relate to food safety. Trichinella parasites in pork are killed at 137°F (58°C) and should be cooked a little higher for safety. Various health agencies recommend cooking meats to at least 145°F (63°C) to destroy all pathogens, with some extending that up to 160–165°F (70–74°C) for ground meats and poultry. However, microbes like bacteria should not be present on the interior of a completely intact and properly prepared piece of healthy muscle, which provides some leeway with certain large animals like beef.

Resting

When cooking larger pieces of meat using dry heat, it is a good idea to let it rest at room temperature between removing it from the heat and serving it. This achieves several things. First, it allows for carryover heat to finish cooking the meat through to the desired temperature. It also lets it cool to a suitable serving temperature, improves the water-holding capacity and reduces loss of juices, and redistributes the existing juices in the meat. It does not, however, allow the meat to "relax" as is sometimes believed.

In general, the larger the piece of meat, the longer the required resting time. Depending on the size, the resting period can range from anywhere from 10 minutes to an hour or two. As a general rule to guide you, try 3–5 minutes of rest time per pound of meat. Note that resting to the extent that the meat over-cools can cause the fat and gelatin to congeal, making the meat feel stiffer and tougher.

Carving and shredding

Carving refers to the process of cutting meat off a large cut such as a roast. It is typically cut against the grain and with a very sharp blade to avoid squeezing out moisture. Shredding is when the fibers of well-done muscle meat are pulled apart along the grain.

Reheating

Leftover cooked meat should be reheated quickly and then immediately served. If reheating in liquid such as a stew, bring the liquid to the boil, then add the meat and let it heat through below the boil. Reheated meat may have a slight off flavor due to oxidation and rancidity of unsaturated fats.

Index

Organ meats

Poultry

Processed meats

Beef

Bison

Dog

Edible dormouse

Frog

Game

Goat

Guinea Pig

Horse

Iguana

Kangaroo

Lamb and Mutton

Meat - 1881

Organ Meat

Pork

Rabbit

Sausage Casing

Veal

Venison

Recipes

Recipes using meat

Recipes using beef

Recipes using bison

Recipes using dog

Recipes using frog

Recipes using game

Recipes using goat

Recipes using iguana

Recipes using insects

Recipes using lamb and mutton

Recipes using organ meat

Recipes using pork

Recipes using poultry

Recipes using processed meat

Recipes using rabbit

Recipes using snail

Recipes using veal

Recipes using venison

Abula (Nigerian Three Stews)

Albanian Fried Meatballs

Algerian Chakhchoukha (Vegetable and Flatbread Stew)

Ayamase Jollof Rice

Bacon and Egg Stuffed Tomatoes

Banga Soup

Bassi-Salté (Senegalese Couscous with Meat and Vegetables)

Benachin (Gambian Rice with Meat and Vegetables)

Biltong (Zambian Dried and Salted Meat)

BLT Sandwich

Broccoli Stir Fry

Bulgarian Fresh Sausage (Kebapcheta)

Burgoo

Burrito Mix

Cachupa (Cape Verdean Corn Stew)

Cassoulet

Chili with Meat

Döner Kebab

Dum ka Qimah (Spiced Minced Meat)

Dumboy and Pepper Soup

Farofa

Gambian Caldo (Seafood soup)

Gambian Superkanja Soup

Gboma Dessi and Akoume (Togolese Spinach Stew with Corn Swallow)

Hyderabad Biryani

Jambalaya I

Kibbeh

Leaf Masala Curry

Lemon Chicken Pasta

Liberian Cassava Leaf Soup

Liberian Eggplant Stew

Liberian Potato Greens

Lo Mein

Luwombo (Ugandan Steamed Meat and Vegetables)

Maffé (West African Peanut Stew) I

Meat and Rice-Stuffed Bell Peppers

Microwave Quesadilla

Miyan Karkashi (Nigerian Sesame Leaf Soup)

Miyan Kuɓewa (Okra Soup)

Miyan Lalo (Hausa Jute Leaf Soup)

Miyan Shuwaka (Hausa Bitter Leaf Soup)

Moussaka (Bulgarian)

Muskrat Soup

Ofe Owerri

Okonomiyaki (Japanese Savory Pancake)

Ora Soup II

Original Texas-Style Chili

Ossobuco Alla Milanese

Osumade Soup

Owo Soup

Palaver Sauce

Pedernales River Chili

Pezzetti di Cavallo (Italian Horse and Tomato)

Cuban Picadillo

Pork Stomach Filled with Meat and Vegetables (Saumagen)

Portuguese Feijoada

Rice Cooked in Tomato Meat Sauce (Ross il-Forn)

Rice Tamale (Pastel de Arroz)

Riz Gras (West African Fried Rice)

Roasted Brined Turkey II

Rosto

Saka-Saka (Cassava Leaf Stew)

Sauce Feuilles (Greens Stew)

Steak and Peppers

Stuffed Peppers

Sylheti Biryani

Sylheti Doner Kebab

Taco Meat

Tchakpolo (Togolese Meat and Vegetable Stew)

Tempura

Texas Easy Chili

Tibs (Ethiopian Sauteed Meat and Vegetables)

Traditional Pilau Rice

Ukazi Soup

Zambian Beef Stew