A darkcutter or dark cutter (also known as DFD, or Dark Firm Dry) is a carcass of
beef
Beef is the culinary name for meat from cattle (''Bos taurus'').
In prehistoric times, humankind hunted aurochs and later domesticated them. Since that time, numerous breeds of cattle have been bred specifically for the quality or quantit ...
that has been subjected to undue
stress
Stress may refer to:
Science and medicine
* Stress (biology), an organism's response to a stressor such as an environmental condition
* Stress (linguistics), relative emphasis or prominence given to a syllable in a word, or to a word in a phrase ...
before
slaughter, and is dark in color. Sometimes referred to as dark cutting beef, they have a dark color which makes the meat appear less fresh, making them undesirable to consumers. Darkcutters fetch a lower price than otherwise ordinary beef on the market.
Desirable meat has a slightly acidic pH level, from 5.3 to 5.7, which is a result of the conversion of
glycogen to
lactic acid
Lactic acid is an organic acid. It has a molecular formula . It is white in the solid state and it is miscible with water. When in the dissolved state, it forms a colorless solution. Production includes both artificial synthesis as well as nat ...
. Poor feeding or handling will mean that no glycogen is available, so lactic acid cannot be produced to lower the pH.
Stress ''ante mortem'' causes a depletion of glycogen stores in the
liver
The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it ...
and
muscles. Thus the
glucose
Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, u ...
normally used ''post mortem'' to produce
ATP anaerobically and in turn resulting in lactic acid production before the development of ''
rigor mortis
Rigor mortis (Latin: ''rigor'' "stiffness", and ''mortis'' "of death"), or postmortem rigidity, is the third stage of death. It is one of the recognizable signs of death, characterized by stiffening of the limbs of the corpse caused by chemic ...
'', is unavailable. The muscle
pH stays high (above 6.0), resulting in higher water-holding capacity (sticky protein) and more translucent muscle, which looks darker because light travels deeper into the muscle before being
refracted
In physics, refraction is the redirection of a wave as it passes from one medium to another. The redirection can be caused by the wave's change in speed or by a change in the medium. Refraction of light is the most commonly observed phenomeno ...
.
To prevent and address darkcutting, it is suggested to keep the animals calm and well fed before culling. If the livestock do not consume enough nutrition, or deplete it while stressed by poor handling, the levels of glycogen will be reduced. Severe stress leads to a proportionate depletion in the animal's glycogen.
See also
*
PSE meat Pale, soft, exudative meat, or PSE meat, describes a carcass quality condition known to occur in pork, beef, and poultry. It is characterized by an abnormal color, consistency, and water holding capacity, making the meat dry and unattractive to cons ...
References
Beef
Meat industry
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