Why Do Chickens Have White and Dark Meat
What Causes Color / Tenderness / Chicken Meat
Type 1 Muscles – Dark – Slow Twitch
Why Do Chickens Have White and Dark Meat – Chickens have “dark meat” in their legs and thighs, while chicken breasts contain “white meat”. This is due to the types of activity those muscles are designed to engage in. “Dark meat” would be classified as Type I skeletal muscle. This type contains myoglobin, an oxygen-binding protein that is related to hemoglobin in red blood cells, which makes Type I muscle appear red.
Type I muscles are suited for endurance activity and are slow to fatigue because they use oxygen to generate energy (mostly aerobic metabolism). “White meat” would be classified as Type II skeletal muscle. This type does not contain myoglobin, so it does not appear red.
Type 2 Muscles – White Meat – Fast Twitch
Type II muscles are suited for short, quick bursts of activity and are quick to fatigue because they rely on glycolysis for energy production (mostly anaerobic metabolism). Chickens primarily run and walk, so their legs and thighs are built for endurance activity.
Thus, legs and thighs contain Type I muscles, or “dark meat”. Chickens only use their flight muscles for very short bursts of activity, so their breast meat is made up of Type II muscles, or “white meat”.
Ducks / Quail – Dark Meat in Breast
This also explains why birds that fly more, for longer periods of time (e.g. duck, quail), have “dark meat” as their breast meat.
Myoglobin is the hemoprotein (an oxygen-carrying protein) responsible for giving dark meat its reddish color. The more myoglobin, the darker the meat and the richer the nutrients.
Myoglobin provides muscles with the oxygen they need during exercise or movement. Since chickens are flightless birds, they use their legs and thighs to get around, making them darker than the breast or wings.
What’s the Difference Between White and Dark Chicken?
Different muscles in the animal are used to do different things. Dark cuts, like the drumsticks and thighs, are used for holding the animal up and walking, so they are required to work for long, sustained periods of time. Whereas, white cuts like the breast and wings are required to perform short bursts of energy, like flapping their wings.
The dark and white cuts of meat apply to both chicken and turkey. Because these muscles have different uses, they have different types of metabolism. In contrast, breast meat of duck is actually dark meat because ducks fly and use that muscle for long, sustained periods of time. Dark meat cuts come from muscles that use more oxygen and have more iron.
The iron is held in a protein called myoglobin, which gives it a darker color. White meat cuts come from muscles that metabolize energy with less oxygen, so they have less myoglobin and are lighter in color. All chicken is a good source of protein, as well as niacin, vitamin B-6, biotin, and vitamin B-12.
Dark Meat Contains More Iron
The experts say there is a slight difference in chicken nutrition between white and dark meat. Dark meat, because of the type of muscle, has slightly more iron. The biggest difference is the number of calories and fat in the pieces. Typically, a boneless, skinless breast and breast tenders will have the least fat and fewest calories of any cuts of chicken. Dark meat will have more fat, but much of this comes from fat in between muscles.
Since the leg meat (drumstick and thigh) is made up of multiple muscles, there is generally more fat than white meat. Furthermore, fat around the breast meat cut (one single muscle) is more easily trimmed than fat in between muscles found in the leg. Fat in chicken is most often found in the skin, she explained.
So, boneless skinless breast (white meat) and skinless thighs (dark meat) are both relatively lean cuts of meat. Pieces with the skin, typically drumsticks and wings, have higher fat content.
How Do the Cuts of Meat Compare in Taste and Flavor?
Dark meat – Stronger Flavor – Increased Fat Content
Dark cuts like the drumstick and thigh have a little bit stronger flavor, mostly due to increased fat content because many flavor compounds are fat-soluble. Additionally, the dark meat will tend to be juicier, again due to the increased fat content.
White Meat Milder Flavor – Less Fat Content
White meat cuts are milder in flavor and may need flavors added to them, whereas dark meat cuts are able to stand on their own in the flavor department.
When cooking chicken, keep in mind the type of meat to determine the best way to prepare it. White meat can tend to dry out quickly so it is helpful to cook in a moist environment, such as baking or in a covered skillet, and to avoid overcooking. Using a meat thermometer to cook to 165 F, and not substantially more, is helpful with this.
Most Popular Types of Chicken Meat
It seems that white meat is more popular. We asked the experts what might be the reasons for that.
Breast meat tenders (white tenderloin muscle that lies underneath the breast muscle) are very popular due to the serving size and its use in fried foods. Fried foods are still very popular in fast food and foodservice. The other white meat cut is wings and they have been made popular by their size and the ‘buffalo wing’ craze in appetizers and snacks.
Factors Affecting Poultry Meat Quality
There are a number of characteristics that determine the overall quality of meat, like appearance, texture, and flavor.
Poultry meat color is affected by factors such as birds age, sex, strain, diet, intramuscular fat, meat moisture content, pre-slaughter conditions, and processing variables.
Color of meat depends upon the presence of the muscle pigments myoglobin and hemoglobin.
Discoloration of poultry can be related to the amount of these pigments that are present in the meat, the chemical state of the pigments, or the way in which light is reflected off of the meat.
The discoloration can occur in an entire muscle, or it can be limited to a specific area, such as a bruise or a broken blood vessel. When an entire muscle is discolored, it is frequently the breast muscle.
This occurs because breast muscle accounts for a large portion of the live weight (about 5 percent), it is more sensitive to factors that contribute to discoloration, and the already light appearance makes small changes in color more noticeable.
Extreme environmental temperatures or stress due to live handling before processing can cause broiler and turkey breast meat to be discolored. The extent of the discoloration is related to each bird’s individual response to the conditions.
Discoloration of Bruised Meat
Another major cause of poultry meat discoloration is bruising. The poultry industry generally tries to identify where (field or plant), how, and when the injuries occur but this is often difficult to determine.
The color of the bruise, the amount of ‘blood’ present, and the extent of the ‘blood clot’ formation in the affected area are good indicators of the age of the injury and may give some clues as to its origin.
Discoloration During Catching / Transportation / Processing
A bruise will vary in appearance from a fresh, ‘bloody’ red color with no clotting minutes after the injury to a normal flesh color 120 hours later. The amount of ‘blood’ present and the extent of clot formation is useful in distinguishing if the injury occurred during catching/transportation or during processing. Injuries that occur in the field are usually magnified by processing plant equipment or handling conditions in the plant.
After consumers buy a poultry product, they relate the quality of that product to its texture and flavor when they are eating it. Whether or not poultry meat is tender depends upon the rate and extent of the chemical and physical changes occurring in the muscle as it becomes meat.
When an animal dies, blood stops circulating, and there is no new supply of oxygen or nutrients to the muscles. Without oxygen and nutrients, muscles run out of energy, and they contract and become stiff. This stiffening is called rigor mortis.
Eventually, muscles become soft again, which means that they are tender when cooked. Anything that interferes with the formation of rigor mortis, or the softening process that follows it, will affect meat tenderness.
For example, birds that struggle before or during slaughter cause their muscles to run out of energy quicker, and rigor mortis forms much faster than normal.
Environmental Stress Pre-Slaughter
The texture of these muscles tends to be tough because energy was reduced in the live bird. A similar pattern occurs when birds are exposed to environmental stress (hot or cold temperatures) before slaughter. High pre-slaughter stunning, high scalding temperatures, longer scalding times, and machine picking can also cause poultry meat to be tough.
Tenderness of portioned or boneless cuts of poultry is influenced by the time post-mortem of the deboning. Muscles that are deboned during the early postmortem still have energy available for contraction. When these muscles are removed from the carcass, they contract and become tough. To avoid this toughening, meat is usually ‘aged’ for 6 to 24 hours before deboning. However, this is costly for the processor.
When poultry is deboned early (0 to 2 hours post-mortem), 50 to 80 percent of the meat will be tough. On the other hand, if the processor waits 6 hours before deboning, 70 to 80 percent of the poultry meat will be tender.
The poultry industry has recently started using post-slaughter electrical stimulation immediately after death to hasten rigor development of carcasses and reduce ‘aging’ time before deboning. This is different from energy depletion in the live bird, which causes meat to be tough. When electricity is applied to the dead bird, the treatment acts as a nerve impulse and causes the muscle to contract, use up energy, and enter rigor mortis at a faster rate.
In the live bird, the same treatment causes meat to be tough but after death, the treatment causes tender deboned poultry meat within two hours post-mortem instead of the four to six hours required with normal aging.
The flavor is another quality attribute that consumers use to determine the acceptability of poultry meat. Both taste and odor contribute to the flavor of poultry, and it is generally difficult to distinguish between the two during consumption.
When poultry is cooked, the flavor develops from sugar and amino acid interactions, lipid and thermal oxidation, and thiamin degradation. These chemical changes are not unique to poultry but the lipids and fats in poultry are unique and combine with odor to account for the characteristic ‘poultry’ flavor. Few factors during production and processing affect poultry meat flavor.
This means that it is not only difficult to produce a flavor defect but it is difficult to enhance flavor during production and processing. The age of the bird at slaughter (young or mature birds) affects the flavor of the meat.
Minor effects on meat flavor are related to bird strain, diet, environmental conditions (litter, ventilation, etc.), scalding temperatures, chilling, product packaging, and storage. However, these effects are too small for consumers to notice.
There is a lot of factors that influence consumption and in the production of White / Dark Meats Poultry Meats for Eating.
- Types of Muscles Type 1 / Type 2
- Type of Poultry Bird
- Amount of Exercise the Birts was produced under
- Environmental Conditions in Feeds / Nutritions
- Environmental conditions in Processing
- Speed of Processing
- Care was taken in processing / Bruising
- Customer Demands – White / Breast / Wings
Rabbit Meat Profitability Table
|Rabbits||Rabbits Born||Lbs Meat / Year||Average Price / LB||Total Revenue Possible|
|1||84||252||$ 8.00||$ 2016|
|2||168||504||$ 8.00||$ 4032|
|5||420||1260||$ 8.00||$ 10,080|
|10||840||2520||$ 8.00||$ 20,162|
|20||1680||5040||$ 8.00||$ 40,320|
|30||2520||7560||$ 8.00||$ 60,480|
|40||3360||10,080||$ 8.00||$ 80,640|
|50||4200||12,600||$ 8.00||$ 100,800|
|100||8400||25,200||$ 8.00||$ 201.600|
|200||16,800||50,400||$ 8.00||$ 403,200|
Rare Breed Chicken Farming
|Rare Breeds||Country of Origin||Eggs/Week||Average Weight||Price / Chicks|
|Black Penedesenca||Spain||3-4||4-5lbs||$ 13.43|
|Black Sumatra||Sumatra||4 / Tinted in Color||4lbs||$ 4.56|
|Ameraucana||United States / Chile||3 / 4 Blue||5 lbs||$ 4.25|
|Lavender Orpington||England||4 / 5 Brown||5 lbs||$ 6.08|
|Partridge Chantecler||Canada||3-5 / Brown||7 lbs|
|Wyandotte||United States||3 - 5 / Tinted Brown||6 lbs||$ 4.90|
|Welsummer||Welsum Netherlands||4 / Dark Brown||5 lbs||$ 5.95|
|Silver Grey Dorking||UK / Roman||8 lbs||$ 5.95|
|Light Brahma||United States / China||Brown||13 lbs||$ 4.90|
|Silver Laced Cochin / Shanghai||China||5-6 / Brown||6 lbs||$ 4.90|
|White Marans||Marans / France||4 / Dark Brown||5 lbs||$ 6.08|
|Dominiques||United States||4 - 5 / Brown||7 lbs||$ 4.90|
|Exchequer Leghorn||Tuscany Italy||White||5 lbs||$ 4.25|
|Silver Spangled Appenzeller|
|Buff Brahma Standard||Shanghai China||Brown||13 lbs||$ 4.90|
|Silver Laced Polish||Poland / Netherlands||4-5 lbs||$ 5.95|
|White Sultan / Fowls of the Sultan||Turkey||2 - 3 / White||4-6 lbs||$ 7.75|
|Mottled Houdan||Houdan Paris France||White||4 - 5 lbs||$ 7.75|
|Dong Tao / Dragon Chicken||Vietnam||2/3||$ 2500 -|
|Ayam Cemani||Indonesia||3 / Cream||5 lbs||$ 50 - $ 2500|
|Onagadori / Honorable Chicken||Japan||$ 49.00|
|Polverara||Italy||2 / 3|
|Ixworth||Sussex UK||4 / Cream|
|Naked Neck / Transylvanian Naked-Neck chickens.||Transylvania||5||$ 4.25|
|Campaign||Belgium||7 / White||5 lbs||$ 7.75 / Golden|
|Deathlayer /||German||7 / White||$ 99.00|
|Serama / Smallest Chicken in the World||Thailand||.5 - 1 Lb||$ 39.00|
|Silkie / Silky||Chinese||2 / Cream||$ 5.75 / White $ 5.75 / Blue $ 5.75 / Buff
$ 5.75 / Black
Types of Chicken Breeds
|Chicken Breeds||Origin||Meat/ Layers / Dual Purpose||Finished Weight||Eggs per Week||Weeks to Slaughter|
|Broilers||Canada/US/Europe||Meat||3.3 lbs||5||14 Weeks|
|Cornish crosses||England||Meat||6.5 - 8.5 lbs||3||8 - 9 Weeks|
|Jersey Giants||USA||Meat ( Intended to replace Turkeys)||13 lbs||4||8 - 9 Months|
|Hertigage Breeds||6 - 9 months|
|Delaware||USA Delaware||Duo||6.5 lbs||4 - large||8 Months|
|Dorking||United Kingdom||Duo||10 - 14 lbs||5 - med||5 Months|
|Buckeye||USA Ohio||Duo||6 - 9 lbs||4 - med||5 Months|
|Rhode Island Red||USA Rhode Island||Duo||6 b- 8 lbs||5-6||5 Months|
|Leghorn||Italy||Eggs||4 -5 lbs||4||8 Months|
|Plymouth Rock||USA - Massachusetts||Duo||7.5 lbs||4||5 Months|
|Sussex||United Kingdom||Duo||7 lbs||4 - 5 - large||5 Months|
|Wyandotte||Canada||Duo||7 - 9 lbs||5 Months|
|Welsummer||Netherlands||Duo||7 lbs||4 / Week||5 Months|
|Hamburg||United Kingdom||Eggs||7 lb||4 - med||9 weeks|
|Black Australorp||Australia||Duo||\3 - 5 lb||5 - med||5 months|
|Buff Orpington||England||Duo||7 - 8 Lbs||4 - 5||8 months|
|Brahma||Meat||11 lbs||3 - med||5 monthss|
Dual Purpose Breeds
Chicken / Poultry Breeder Associations
|US Poultry & Egg Association||United States||USPA|
|American Poultry Association||California||APA|
|Ohio Poultry Association||Ohio||OPA|
|National Chicken Council||United States||NCC|
|British Poultry Council||United Kingdom||BPCE|
|Poultry Club of Great Britain||United Kingdom||PCGB|
|Association of Poultry Breeders in EU||Europe||AVEC|
|Australian Chicken Meat Federation Inc||Australia||ACMF|
|Australian Poultry Hub||Australia||Poultry Hub|