Last Updated on September 16, 2022
The reason for this iridescent sheen in meat is complex. It depends on several factors, including the age, breed, sex, diet, and exercise. Meat can be a light red or intense purple color, depending on its age, species, dietary content, and exercise level. Myoglobin content varies according to muscle activity, species, and diet. Lamb and beef have higher myoglobin contents than pork, but the color of these two meats is not consistent.
Immature animals have lower myoglobin levels
The myoglobin content of meat can be affected by several factors, including size and basal metabolic rate. Smaller animals have lower myoglobin levels than larger ones, so their meat will be lighter in color. Larger animals, such as deep-diving whales, have higher myoglobin levels than small animals, such as horses. Game animals have higher myoglobin levels than domestic animals, such as venison and bison, and they tend to have darker muscles than domestic animals.
While meat color is an important sensory evaluation parameter, the content of myoglobin in meat depends on the animal’s age, exercise, and storage. Meat with higher levels of myoglobin is typically red in color. In comparison, meat that has been cooked to a well-done level will be grayish-brown. Immature animals have lower myoglobin levels, which will affect how red meat will turn out.
The colour of meat is associated with two proteins: myoglobin and iron. Myoglobin reacts with oxygen when in contact with meat, attempting to reach an equilibrium. Meat colour is affected by three different stages. A purplish red colour develops right after cutting meat. Cherry red appears a few minutes later after the meat has been exposed to oxygen. This colour is attributed to the higher concentration of slow-twitch fibers in meat.
Myoglobin reacts with oxygen in an attempt to reach a state of equilibrium
Myoglobin reacts with oxygen in a process called oxidation to darken meat when cooked. It has three different forms: metmyoglobin, oxymyoglobin, and deoxymyoglobin. When meat is cooked, this reaction slows down as the temperature increases. The higher the temperature, the slower the loss of red colour. Higher temperatures slow down the process, and the green and blue values do not change significantly over time.
The rate at which myoglobin converts into metmyoglobin varies across the meat. Oxymyoglobin is converted to metmyoglobin by reacting with oxygen. This reaction is complex, but is responsible for the brown colour of meat. In the process of cooking, the meat undergoes oxidation and the resulting brown colour is metmyoglobin.
The amount of pigmentation within meat affects its appearance when it is raw. Meats that are cut without oxygen show a reddish color, while meat that is fully cooked appears black. This is due to oxidation of the iron contained in myoglobin. Cooking can denature some myoglobin. While myoglobin is denatured at high temperatures, a small amount of it remains.
The level of myoglobin is a major sensory determinant of meat color. The levels of myoglobin in a meat vary according to the age and breed of the animal. In a study of pigs, the proportion of myoglobin in meat was significantly related to its color. However, the MDH activity and LA level were lower in a fatty cut of pork than in beef.
Myoglobin loses its ability to bind oxygen above 140deg F
Meat contains three different types of myoglobin. They are deoxymyoglobin, oxymyoglobin, and metmyoglobin. Depending on the amount of oxygen that the meat is exposed to, myoglobin can have one of these colors. Deoxymyoglobin gives meat a purple red color. It is typical to see this color in vacuum-packed meat, or late in the display of meat. At this point, the iron in the pigment oxidizes, and the meat turns tan or brown.
The color of myoglobin is determined by the pigment related proteins in the meat. Red meat has more myoglobin than white meat, which is a result of red meat’s higher myoglobin content. Heavyly exercised muscles need more oxygen to function properly. Therefore, they have more myoglobin than a meat without much exercise. A meat with a high amount of myoglobin will look brighter.
Beef and lamb are red because they contain more myoglobin than white meat. Chicken, on the other hand, is white because it lacks this substance and therefore is classified as white meat. However, meat color depends on other factors such as age, exposure to oxygen, and muscle use. Chicken thighs are darker than chicken breasts. In addition, chicken thighs are red because they are more heavily coloured than chicken breasts.
Iridescent sheen of meat
What causes the iridescent sheen on your meat? It is a complex process that is directly related to the type of light reflecting off the surface and the type of light hitting the surface. It is also influenced by the condition of the meat, with a smooth surface exhibiting more vivid iridescence than a rough one. However, meat that is too dark will not show this sheen as vividly.
This unique appearance is the result of chemical compounds in the meat. When light passes through meat, the proteins in the meat reflect back or split and the result is an iridescent sheen. Uncooked beef is red due to iron-bearing compounds, which then absorb the red hues from the refracted light to give the meat its green color. As a result, the meat appears to have a rainbow color.
Curing solutions for meats contain phosphates, which help to improve moisture retention and render the surface of the meat smoother. The curing process also allows the meat to be tumbled after injection to release sufficient proteins. These proteins fill voids in between muscle fibers and improve the reflectance of the meat. Therefore, iridescent meats are a great option for people who like to serve their families with food that will have them talking for years to come.
Carbon monoxide
Carbon monoxide is a byproduct of meat processing. This gas is about 200 times more powerful than oxygen, so it can easily replace the oxygen in hemoglobin. The gas is a common additive to processed meats, which keeps them red for a long period of time. Meat was not vacuum sealed to prevent it from turning black, but that isn’t always the case. In a recent study, scientists found that carbon monoxide treatment keeps meat red, even after it spoils.
Although the chemical nitrites are responsible for meat turning black when cooked, they are not responsible for carbon monoxide poisoning. In some cases, meat remains pink when exposed to nitrites. Alternatively, packagers can artificially keep meat pink to increase sales. This chemical process is similar to the use of red colorants in meat packing. Acute exposure to carbon monoxide can cause fatal consequences if the poisoning isn’t detected immediately.
The dangers of CO poisoning are clear: it is difficult to detect its presence in the body, and the symptoms can be incredibly unpleasant. However, if the poisoning is severe enough, a victim may even faint. Fortunately, there are ways to protect yourself from its effects, though. First, you should have a carbon monoxide alarm installed in your home. Many detectors come with a digital readout and emit a high-pitched sound when the CO level is elevated. If the carbon monoxide level reaches 70 parts per million, the person may experience a headache and fatigue. At 150 to 200 ppm, CO can cause disorientation and unconsciousness, and even cause death.
Lack of oxygen
When you cook meat at a high temperature, oxygen is forced to leave the animal tissue because it competes for oxygen with the pigment myoglobin. Myoglobin is a protein that contains iron and is responsible for storing oxygen in muscles. While most muscles have more of this pigment than others, the red colour associated with oxymyoglobin occurs only when the animal is under high oxygen levels.
When meat is stacked on top of each other, its oxygen partial pressure drops. Because of this, the meat loses its red color. Ground beef, for example, lacks oxygen, and it loses its red color over time. The process of changing from red to brown is easy, but reversing it requires the addition of oxygen. When the animal has been exposed to low oxygen levels for a long period of time, myoglobin stops mixing with oxygen to keep it red.
The protein myoglobin is responsible for the majority of red colour in meat. Myoglobin is a purplish colour, and when it combines with oxygen, it produces oxymyoglobin, a bright red pigment. Hemoglobin is responsible for the rest of the meat’s red colour. It is present in circulating blood and small amounts are found in tissues after slaughter.
About The Author
Gauthier Daniau is a freelance problem solver. He first discovered his knack for trouble-shooting when he was still in diapers - and hasn't looked back since. When he's not slaying zombies or internet ninjas, GAUTHIER enjoys working with animals of all shapes and sizes. He's also something of a social media expert and loves to get lost in numbers and figures.