Meat is the most valuable livestock product since it is one of the main sources of protein for human consumption. Meat quality can be evaluated according to the following parameters: pH, amount of lactic acid, volatile fatty acids, bounded water, solubility of proteins, color, and tenderness. The meat composition and physical properties of muscles have been characterized for ensuring improved eating quality. Thus, the purpose of this paper was to review the major chemical compositional and physicochemical properties of meat and, at the same time, its quality attributes and factors that affect quality of meat. A number of structural features of meat as connective tissue, muscle fibers, and tendon that attaches the muscle to the bone are visible in joint meat examined through naked eyes. Water is quantitatively the most important component of meat comprising up to 75% of weight. Meat is also composed of amino acids, fatty acids, vitamins, minerals, and other important ingredients. Quality factors perceived by consumers are related to sensory attributes (e.g., color, tenderness, and flavor), nutritional properties (e.g., calories, vitamins’ content, and fatty acids’ profile), and appearance (e.g., exudation, marbling, and visible amount of fat). However, fresh meat quality can be defined instrumentally including composition, nutrients, color, water-holding capacity, tenderness, functionality, flavors, spoilage, and contamination. Visual inspection based on sensory quality attributes and different chemical methods are used to analyze meat quality. Other methods such as computer vision and imaging spectroscopy, gas chromatographic analysis, near-infrared technology, dual-energy X-ray absorptiometry, and computerized tomography scanning are also used in the meat industry. So, the aim of the present review is to review quality characteristics of cattle meat and its composition constituents.
The general increasing human population in the world leads to the movement of people from rural areas to urban. This will increase the demand for food of livestock origin [
The chemical composition and physical properties of meat determined the quality of meat (pH, color, water-holding capacity, hardness, thermal treatment losses, nutritional value of meat proteins, digestibility, etc.). These characteristics are influenced by animal species, breed, individual characteristics, sex, age, rearing technologies, and fattening, as well as other factors such as meat production procedure (feeding, transporting, and slaughtering condition) and processing (storage time or temperature condition) [
From the consumer perspective, quality is related to functional characteristics that range from sensory domain taste and appearance properties to cost domain storage and distribution criteria.
Among the sensory traits of meat, color, tenderness, flavor [
The consumers decide the quality of fresh meat during purchases by using its color which is an important property to determine the quality of meat. Discolored meat is related to the conversion of oxymyoglobin to metmyoglobin in the chuck and round muscle [
Quality factors perceived by consumers are tied to nutritional properties (i.e., calories, vitamins’ content, and fatty acids’ profile) and appearance (i.e., exudation, marbling, and amount of fat) [
The meat quality determination always depends on the structure of muscle meat, including intrinsic structure (sarcomere length, myofilament diameter, and fiber types) and basic chemical composition of meat (moisture, protein, ash, and collagen content). The strongest single beef quality attribute is the marbling score, so in many countries, it is the basis for the carcass evaluation [
To review on the chemical composition and physiochemical characteristics of meat quality and factors affecting the meat quality of cattle carcasses.
To discuss basic meat quality attributes in terms of tenderness, flavor, pH value, water-holding capacity, marbling, and color To overview the basic chemical composition of cattle meat To review the method of analyses on the quality and composition of meat and factors that affect meat quality
Meat is not only an important source of amino acids, minerals, and vitamins but also a good source of energy [
The common features of the meat structure such as connective tissue, muscle fibers, and tendon which attaches the muscle to its bone are visible in joint meat examined through the naked eye [
Water is quantitatively the most important component of meat comprising around 75% of weight [
From the nutritional and processing meat point of view, protein is the most valuable component in meat. It is the building block of the muscular tissue. Protein is a complex molecule made up of simple organic molecules known as amino acids [
The fat portion of meat includes some fat-soluble substances, including some vitamins [
Main fat properties are determined by the composition of its main component as fatty acids [
The fatty acid composition of adipose tissue affects its firmness because different fatty acids have different melting points. The composite fatty acids of meat melt between about 25°C and 50°C, with SFA melting at higher and PUFA at lower temperatures [
As consumers of different goods, we always attach great importance to the quality of the products and especially to the quality of consumed food. The word “quality” can be determined differently by different people and has many meanings, and thus, it is a relative concept. However, in ISO 9000 : 2000, “quality” is defined as “the totality of features and characteristics of a product or service that bear on its ability to satisfy stated or implied needs.” [
Meat is one of the most important foods in the diet for the vast majority of people, particularly in the developed world [
In every case, meat quality evaluation starts with the quality control of raw meat [
pH of meat is an important indicator of quality meat from the perspectives of its processing technologies and storage. The crucial pH value of meat (measured at approximately 24 hours after slaughter) is a direct consequence of muscle glycogen (energy) levels at slaughter. Ultimate pH of the meat determines the meat color, water-holding capacity, and texture, all of which affect the meat quality [
Meat color is dependent on species, age, and muscle type, and the color differences are due to different contents of myoglobin in the muscle [
Raw meat has little aroma, but meat flavor is developed because of several compounds produced in the postmortem muscle [
The amount of intramuscular fat deposited in the longissimus muscle (marbling) is a major determinant of carcass quality and predictor of palatability. Marbling is related to muscle firmness, flavor, and juiciness. It is a very significant factor in meat quality evaluation [
Consumer studies have revealed that tenderness is the most important factor of meat eating quality [
Juiciness of meat is very important with respect to eating quality, and it is influenced by many factors such as ultimate pH, fat content, marination, cooking method, and degree of doneness [
Treatment of carcass surfaces with organic acids can have a positive result in the inhibition of microbial growth. Lactic acid (LA) is a naturally occurring acid and is used effectively by the food industry during food processing. Table
Effects on meat quality traits by lactic and/or acetic acid application [
Acid | Appl. conc. | Substrate | Changes | Reference | |
---|---|---|---|---|---|
A | S | 2% | Beef carcass | Col. | Osthold et al. [ |
L | S | 1% | Beef carcass | Col. | Osthold et al. [ |
L | S | 1.25% | Veal carcass | None | Smulders and Woolthuis (1985) |
L | S | 1% | Pork carcass | None | Prasai et al. [ |
L | S | 2.4% | Pork carcass∗ | Col. | Labots et al. [ |
A | S | 2% | Pork loin | Col. | Cacciarelli et al. [ |
A/L/M | S | 1% | Beefsteak | None | Dixon et al. [ |
A/L/M | S | 1% | Beef striploins | None | Acuff et al. [ |
L: lactic acid; A: acetic acid; M: mix of lactic and acetic acid; (): reversible changes;
Meat ranks among one of the most significant, nutritious and favored food item available to masses, which aids in fulfilling most of their body requirements. It has played a vital role in human evolution and is an imperative constituent of a well-balanced diet. It is a good source of proteins, zinc, iron, selenium, and phosphorus followed by vitamin A and B-complex vitamins. Tables
Nutritional composition of meat.
Essential amino acids | ||||
---|---|---|---|---|
Amino acids | Category | Beef | Lamb | Pork |
Lysine | Essential | 8.2 | 7.5 | 7.9 |
Leucine | Essential | 8.5 | 7.2 | 7.6 |
Isoleucine | Essential | 5.0 | 4.7 | 4.8 |
Cystine | Essential | 1.5 | 1.5 | 1.2 |
Threonine | Essential | 4.2 | 4.8 | 5.2 |
Methionine | Essential | 2.2 | 2.4 | 2.6 |
Tryptophan | Essential | 1.3 | 1.2 | 1.5 |
Phenylalanine | Essential | 4.1 | 3.8 | 4.3 |
Arginine | Essential | 6.4 | 6.8 | 6.6 |
Histidine | Essential | 2.8 | 2.9 | 3.1 |
Valine | Essential | 5.6 | 5.1 | 5.2 |
Nonessential amino acids | ||||
Amino acid | Category | Beef | Lamb | Pork |
Proline | Nonessential | 5.2 | 4.7 | 4.4 |
Glutamic acid | Nonessential | 14.3 | 14.5 | 14.6 |
Aspartic acid | Nonessential | 8.9 | 8.6 | 8.8 |
Glycine | Nonessential | 7.2 | 6.8 | 6.0 |
Tyrosine | Nonessential | 3.3 | 3.3 | 3.1 |
Serine | Nonessential | 3.9 | 3.8 | 4.1 |
Alanine | Nonessential | 6.3 | 6.2 | 6.4 |
Source: [
Mineral contents (mg/100 g) of meat and meat products.
Meat source | K | Cu | Fe | P | Zn | Mg | Na | Ca |
---|---|---|---|---|---|---|---|---|
Chopped mutton (raw) | 244 | 0.15 | 0.99 | 174 | 4.2 | 18.8 | 74 | 12.5 |
Chopped mutton (grilled) | 303 | 0.25 | 2.5 | 205 | 4.2 | 22.7 | 101 | 17.9 |
Beefsteak (raw) | 335 | 0.1 | 2.4 | 275 | 4.2 | 24.4 | 68 | 5.5 |
Beefsteak (grilled) | 369 | 0.22 | 3.8 | 302 | 5.8 | 25.1 | 66 | 901 |
Source: [
Vitamin content of various raw meat.
Vitamin units/100 g raw meat | Beef | Bacon | Mutton | Veal | Pork |
---|---|---|---|---|---|
A (inter. unit.) | Trace | Trace | Trace | Trace | Trace |
D (inter. unit.) | Trace | Trace | Trace | Trace | Trace |
B1 (mg) | 0.06 | 0.39 | 0.14 | 0.11 | 1.2 |
B2 (mg) | 0.21 | 0.16 | 0.24 | 0.26 | 0.21 |
Nicotinic acid (mg) | 5.1 | 1.6 | 4.99 | 7.1 | 5.2 |
Pantothenic acid (mg) | 0.5 | 0.4 | 0.6 | 0.5 | 0.5 |
Biotin ( | 2 | 8 | 4 | 6 | 5 |
Folic acid ( | 9 | Nil | 2 | 6 | 2 |
B6 (mg) | 0.2 | 0.3 | 0.3 | 0.4 | 0.4 |
B12 ( | 2 | Nil | 2 | Nil | 2 |
C (mg) | Nil | Nil | Nil | Nil | Nil |
Source: [
The characteristics of quality meat vary among species of animal, even within more similar groups such as small ruminants [
Gender effect (male, female, and castrated) is mainly related to the quantity of fat deposited, deposition site, growth rate, and carcass yield. Carcass attributes are more affected by gender; similarly, females are more affected than males due to their higher precociousness, whereas steers maintain an intermediate position. Differences in carcass, fat, and conformation might also affect other meat quality parameters [
The feed of animals usually used has an influence on quality of color, odor, and flavor of meat, but its effects are more evident in fat [
Stress is an imprecise term but can be defined as an animal’s response to any demand made upon it [
Darkening of meat in the DFD condition is due to a higher respiration rate that reduces the depth of oxygen penetration and, therefore, reduces the level of visible oxymyoglobin [
Muscles do not suddenly terminate all their living functions and become meat. A number of physical and chemical changes take place over a period of several hours. These include the onset of rigor mortis and the proteolytic postmortem processes [
The most significant change occurring on death is that circulation stops, and as a result, oxygen is no longer sent to the animal cells. This means that reactions begin to take place under anaerobic conditions [
Shortly after death, the meat appears dark and extremely firm [
The anaerobic glycolysis produces lactic acid via glycogen stores in the muscles [
After slaughter, the postrigor meat is most often conditioned, also called the ageing process. During this process or period, the meat tenderness increases. The period of ageing before the meat reaches a maximum tenderness depends on species; beef needs to be conditioned for minimum ten days [
When the ageing time increased, the difference between WB peak forces between different ultimate pH became smaller [
Meat quality is most often defined as fresh meat eating quality which describes meat for fresh meat consumption and technological quality which describes meat for further processing [
Traditionally, sensory quality attributes are inspected by well-trained assessors. In some abattoirs, tenderness is evaluated using a “finger method.” Meat color and marbling evaluation methods are similar and are usually carried out by comparing ribeye muscle color or the proportion of intramuscular fat within it against reference standards specific for each of the meat species [
Cattle carcasses are classified either manually or automatically using the EUROP grading system. Manual classification is carried out visually by a trained operator at the slaughterhouse, whereas different systems are developed for automatic classification; these are all based on video image analysis (VIA) [
There are other methods to measure meat quality than by chemical analysis. Instruments available only measure a few parameters, but most often, more quality parameter is of interest. CFS MultiTrack is integrated into the grinder and measures fat and lean meat percentage by near-infrared (NIR) technology during mincing [
Another piece of equipment commercially available is the MeatMaster from Foss which not only scans (X-ray) and estimates the fat content of raw meat but also spots metal and bone [
The shear force-deformation curves were obtained; for cooked meat, using a Warner-Bratzler (WB) shear device has suggested that (a) initial yield force values reflected, primarily, the strength of the myofibrillar structure and (b) the difference between initial yield and peak force values was greatly influenced by the mechanical properties of the connective tissue structure. This interpretation was, obviously, simplistic but appeared to accord well with the results obtained using samples subjected to a variety of different treatments including cooking, myofibrillar contraction state, ageing, and, to a limited extent, animal age. There is thus some evidence that the connective tissue contribution to initial yield force values is probably small. Once cooked steak has cooled off, the scientists collect six to eight core samples, each half an inch (1.27 cm) in diameter. They measure the pounds or kilograms of force required to shear the cores completely in half using a steel blade specifically designed to mimic the action of the human jaw. The mean for all the cores is the shear force for the animal. On the Warner-Bratzler system, beef tenderloin typically has a shear force of around 5.7 lbs (2.6 kg). A top round steak has a shear force of around 11.7 lbs (5.3 kg).
Since meat is an important source of essential nutrients, its quality is very important for both consumers and producers, and it depends on different factors. The review shows that quality factors perceived by consumers are related to sensory characteristics such as color, tenderness, and flavor, nutritional properties such as calories, vitamins’ content, and fatty acids’ profile, and appearance such as exudation, marbling, and visible amount of fat. Fresh meat quality can also be defined instrumentally by scientific factors including composition, nutrients, pH, color, water-holding capacity, tenderness, functionality, flavors, spoilage, and contamination. There are numerous methods of measuring meat quality and composition. All the agents within the meat chain from the farm to fork should be evaluated so that quality meat and meat products in terms of durability and acceptability could be obtained (Tables
The data used to support the findings of this study are available from the corresponding author upon request.
The authors declare that they have no conflicts of interest.
The authors acknowledge Oda Bultum University for providing different facilities and reading materials used to prepare this manuscript and it gives full fund. They would like to acknowledge the manuscript presented in Research Square which is entitled Detection of Meat and Fat Quality in Pork and Beef Using X-Ray. In addition to this, they would also like to acknowledge the manuscript presented in UEF/eRepository which is entitled Biochemical and Sensory Profile of Meat from Dairy and Beef Cattle.