Factors Associated with Tenderness of Three Beef Muscles

Tenderness is the prominent quality determinant and probably the most important sensory characteristic of beef steak and roast meat. Currently postmortem aging (storage of carcass at refrigerated temperatures for 8 to 14 days) appears to be the best method for producing tender meat. Although the improvement in meat tenderness as a result of postmortem aging is measurable both subjectively and objectively, the exact mechanism responsible for this improvement in tenderness is unknown. It is well known that different muscles within the same carcass react differently to postmortem storage; for example, tenderloin is tender to begin with and does not improve significantly with postmortem storage, while ribeye is the toughest muscle initially and improves greatly with postmortem storage. The purpose of these experiments was to attempt to answer the following questions: 1)Why are some muscles (e.g., tenderloin) tender at 24 hr postmortem and nonresponsive to postmortem aging? and 2) Why do some muscles (e.g., ribeye and tenderloin) respond differently to postmortem aging

Factors Associated with Tenderness of Three Beef Muscles

Tenderness is the prominent quality determinant and probably the most important sensory characteristic of beef steak and roast meat. Currently postmortem aging (storage of carcass at refrigerated temperatures for 8 to 14 days) appears to be the best method for producing tender meat. Although the improvement in meat tenderness as a result of postmortem aging is measurable both subjectively and objectively, the exact mechanism responsible for this improvement in tenderness is unknown. It is well known that different muscles within the same carcass react differently to postmortem storage; for example, tenderloin is tender to begin with and does not improve significantly with postmortem storage, while ribeye is the toughest muscle initially and improves greatly with postmortem storage. The purpose of these experiments was to attempt to answer the following questions: 1)Why are some muscles (e.g., tenderloin) tender at 24 hr postmortem and nonresponsive to postmortem aging? and 2) Why do some muscles (e.g., ribeye and tenderloin) respond differently to postmortem aging

Effects of Late Castration and Zeranol on Growth Rate, Feed Efficiency, and Carcass and Meat Traits of Bovine Males

It is generally recognized that intact bovine males gain weight faster and require less feed per unit of gain than castrate bovine males. Further, carcasses from intact bovine males have a higher percentage of retail or edible product, but meat from intact males is generally evaluated slightly lower on palatability characteristics, particularly tenderness, than carcasses from castrate bovine males. It has been suggested that much of the advantage of intact vs castrate for rate of gain, efficiency of gain, and composition of gain may be expressed by an age of about 1 year and the disadvantages, including aggressive male behavior, that result in reduced rate and efficiency of gain, begin at about 1 year of age (at or immediately after puberty). Thus, there was need to determine the effects of castration at about 1 year on rate of gain, efficiency of gain, composition of gain, meat characteristics, and behavioral characteristics. Reports have shown that, when the anabolic agent zeranol [6-(6,10-dyhydroxyundecyl)-B-resorcyclic acid-d-lactone] is implanted in intact male calves at or before weaning, rate of gain is increased and rate of testicular growth is decreased. These experiments were conducted to determine the effects of castration and zeranol implants at 13 months of age on rate of gain, efficiency of gain, behavioral characteristics, and carcass and meat traits of bovine males

Muscle Fiber Studies Comparing \u3ci\u3eBos Indicus\u3c/i\u3e and \u3ci\u3eBos Taurus\u3c/i\u3e Cattle

Beef cattle can be classified as either Bos taurus or Bos indicus. Bos taurus breeds of cattle are those originating from Europe,whereas Bos indicus are those breeds originating from India and southeast Asia to include such breeds as Brahman, Sahiwal, Baran, etc. Because of the heat and disease resistance of Bos indicus breeds of cattle, they have been used intensively in the southern U.S. However, some studies have shown Bos indicus breeds of cattle to produce carcasses with less marbling and less tender meat than Bos taurus breeds. Since carcass and meat characteristics are a reflection of the muscle fiber present in the meat, a study was conducted to examine the fiber type characteristics of Bos taurus and Bos indicus breeds of cattle

Variation in Sensory Properties of Meat as Affected by Sex Condition, Muscle, and Postmortem Aging

For several decades, the sensory properties of beef, particularly tenderness, have been of interest to the meat industry. Variations in sensory properties of beef have been attributed to muscle cut or muscle and postmortem aging. The objective of this study was to examine the sensory properties of five beef muscles, determine the contribution of connective tissue (i.e., collagen) to tenderness, and investigate the response of various muscles to postmortem aging

Effect of Subcutaneous Fat Removal on Beef Tenderness

It is now widely recognized that consumers do not accept meat with excessive quantities of fat. To make cuts of meat acceptable to the consumer, packers and retailers are forced to trim much of the subcutaneous fat. If this consumer demand persists, the meat industry will be forced to change its production system to produce leaner cattle. Subcutaneous fat cover is thought to act as an insulator, retarding rapid temperature decline and consequently preventing cold-induced toughness. Cold-induced toughening is a phenomenon observed when prerigor excised muscles are exposed to cold ( \u3c 50° F) temperatures. However, there is no conclusive evidence that cold-induced toughening actually happens under current meat industry practices of slaughtering and carcass handling. The objectives of these experiments were to examine the effect of the removal of subcutaneous fat and high temperature conditioning on beef tenderness. High temperature conditioning (HTC) - storage of carcasses at high temperatures (e.g. 78° F) for 3 to 6 hr after slaughter - was included to attempt prevention of cold-induced toughness in defatted carcasses

Use of Mechanical Tenderization to Increase the Tenderness of Bull Beef

Numerous studies have shown that meat from bulls is less tender than meat from steers of comparable age and feeding regimen. Collagen crosslinking has been reported to be more extensive in bulls than in steers of similar age and has been implicated as a potential cause of toughness in meat from bulls. Several studies have shown that blade tenderization improved the tenderness of beef and decreased the amount of sensory panel-detectable connective tissue. Also, it has been reported that blade tenderization of bull muscles resulted in steaks which required less time to cook, had decreased amounts of detectable connective tissue, and had increased tenderness, flavor, and overall palatability ratings. The objectives of this study were to: (1)determine if mechanical tenderization would increase the tenderness of bull beef to a level equal to that of steer beef; and (2) determine the number of passes through a mechanical tenderizer needed to achieve this desired effect

The Effects of Rate of Change in Body Weight on Tissue Development and Meat Quality of Youthful Bulls

Growth and development of meat-producing animals involves a complex integrated system of changes in the structure and mass of body tissues. Researchers have observed and documented that meat animal growth and development may be altered through the diet or alteration of the sex condition. Most significant alterations are in rates of deposition of protein, fat, and connective tissue, as well as the palatability of the cooked meat. Changes in wt of cattle beyond 14 mo of age have been largely associated with the fat deposition in the body. Studies have shown that youthful bulls have advantages in performance of growth and leanness and disadvantages in tenderness when compared with steers. Differences in tenderness have been attributed to variations in fatness and in connective tissue. Connective tissue has been reported to increase markedly at about 12 mo of age and to decrease in solubility with age. These agerelated changes in connective tissue also have been reported to be more pronounced in bulls than steers. It appears that, as steers are fed dietary energy above maintenance, body protein accretion increases. The alteration in protein content is associated with improved product tenderness. Growth rate over a short period may be a more important determinant of tenderness than the length of time that cattle are fed a high-energy diet. Proteolytic enzymes are needed to increase protein turnover, and these enzymes may also influence postmortem changes in meat properties. Animals gaining or losing wt may alter these enzyme profiles. Therefore, a strong possibility exists that protein turnover is increased and a more youthful connective tissue present during wt gain. This experiment was undertaken to determine the effects of change in body wt on body tissue development and meat quality from youthful bulls

Bison, Hereford, and Brahman Growth and Carcass Characteristics

Bison, Hereford, and Brahman represent three species of the bovine family that evolved under different environmental conditions. There has been much interest in these species and hybrids among them to find animal types that are better adapted to the climatic conditions of the U.S. northern temperate zones down to the subtropical areas. There has been considerable research on growth and carcass characteristics of crosses among British, European, and Brahman cattle types, such as studies at U.S. Meat Animal Research Center. However, there is little experimental documentation of the growth and carcass merit of Bison or their crosses. The three species differ distinctly in conformation, and Bison normally have 14 ribs instead of 13. The experiment described here addresses the differences in growth and carcass characteristics between Bison and two cattle types

Effects of Sex Condition, Diet, and Electrical Stimulation on the Collagen and Palatability of Two Muscles

Meat obtained from intact males has been observed to be less tender than meat obtained from castrated males. Studies have shown that meat from intact males was one sensory panel score less tender than comparable meat from castrated males when animals were fed to about the same age. Reported studies comparing palatability characteristics of meat from bulls and steers have been made on animals fed to similar ages or weights; consequently, compared sex conditions have been confounded with carcass compositional differences. The objectives of the present study were to determine the effects of sex condition and dietary energy density on meat palatability when cattle were fed to the same compositional endpoint