Meat Juiciness and Water Content

According to the Food and Agriculture Organization (FAO), the juiciness of a cooked meat product is closely tied to its capacity to retain water.

The visual appeal of fresh meat is gauged by its ability to hold water, impacting consumers' decision-making when contemplating a purchase. Meat juiciness is a pivotal element in shaping the overall dining experience and is crucial in determining meat texture, thus contributing to its variety.

Improving flavor, assisting in the tenderness of meat for easier chewing, and prompting saliva production in the mouth are among the benefits linked to juiciness. The moisture level and lipid composition are fundamental factors influencing juiciness, with marbling and fat around the edges playing a role in preserving water.

Meat juiciness is thought to arise from the moisture released during chewing and saliva, influenced not only by meat-related factors like fat content but also by the physiological and psychological characteristics unique to individual tasters.

Inadequate water-holding capacity results in reduced cooking yields and often leads to the perception of meat as "dry" due to a lack of juiciness.
Meat Juiciness and Water Content

Meat: Postmortem Muscular Manifestation

Meat constitutes the edible portion derived from the remains of living animals, encompassing both domesticated species like cattle, hogs, sheep, goats, and poultry, and wild animals such as deer, rabbit, and fish.

Considering that the primary constituent of edible animal tissue is muscular, it can be conveniently recognized as the postmortem expression of muscles.

Striated muscles are categorized as either cardiac or skeletal. Cardiac muscles are confined to the heart and are consistently engaged in pumping and circulating blood throughout the body.

Skeletal muscles, identifiable by their striated appearance, are attached to the backbone and participate in voluntary movements, contributing to both locomotion and posture. These muscles exhibit a diverse range of shapes, sizes, anatomical locations, and physiological functions.

The structure of skeletal muscles is intricate, encompassing not only muscle fibers but also connective, adipose, vascular, and nervous tissues. The essential qualities that consumers value in meat, such as color, texture (including tenderness and juiciness), and flavor, hinge on the structural and chemical makeup of the muscle.

Roughly 90% of a skeletal muscle is composed of muscle fibers, while the remaining 10% comprises connective and fat tissues. A muscle is typically enveloped by a dense layer of connective tissue called the epimysium and further divided into bundles of fibers by the perimysium. The individual muscle fibers are encased by a plasma membrane, surrounded by a thin layer of connective tissue known as the endomysium.

Skeletal muscles play a pivotal role in regulating locomotion, maintaining posture, and protecting vital organs. On average, a meat animal carcass contains approximately 100 bilaterally symmetrical pairs of individually distinctive muscles, varying in size, shape, color, and tendon concentration based on their respective functions and locations.
Meat: Postmortem Muscular Manifestation

Cured meat cuts

Meat is a highly perishable item, and its quality begins to deteriorate shortly after the animal is slaughtered. Meat provides an optimal environment for the growth of bacteria, insects, and parasites. Due to its low acidity, improper processing or post-processing contamination can result in bacterial spoilage, making it unsuitable for sale.

The primary objective of curing is to inhibit spoilage and prevent the proliferation of microorganisms. Curing has been practiced since ancient times to safely store meat and prevent foodborne diseases.

Salt and nitrite are the crucial ingredients used in the meat-curing process. Other substances may be added to expedite curing, stabilize color, enhance flavor, and minimize shrinkage during processing. These two key ingredients play a critical role in developing distinct sensory properties that differentiate one cured meat product from another.

Cured meat cuts consist of whole pieces of muscle meat and can be divided into two categories: cured-raw meats and cured-cooked meats. The curing process for both categories, cured-raw and cured-cooked, is fundamentally similar. The meat pieces are treated with small amounts of nitrite, either in the form of dry salt or a salt solution dissolved in water.

The difference between the two groups of cured meats can be summarized as follows:
*Cured-raw meats do not undergo any heat treatment during the manufacturing process. They go through a processing phase involving curing, fermentation, and controlled ripening under specific environmental conditions to ensure the products are palatable. These products are consumed in their raw or uncooked state. Examples of cured meats include dry-cured salami, cooked salami, salt pork, dry-cured salumi, and various other variations. While some types of cured meats can be eaten raw, others like bacon or ham need to be cooked before consumption.

*Cured-cooked meats, on the other hand, always undergo a heat treatment process after the initial curing of the raw muscle meat. This is done to achieve the desired taste and ensure they are safe for consumption.
Cured meat cuts

Marinating meat

Marinade technology has been used in the meat industry for several decades. Marination is commonly used to improve flavor, improve tenderness, and increase shelf life of meat by soaking, injecting or tumbling with an aqueous solutions composed of different ingredients including: water, salt and other ingredients.

An important aspect of marination is the increase of yield of the raw meat, which can provide benefits to the producer and the consumer. Marinating is an effective way to introduce extra moisture into meat that can get too dry when cooked. Marinades soften leaner meats that tend to be dry and make tougher cuts tastier.

Immersion, the oldest method, consists of submerging the meat in the marinade and allowing the ingredients to penetrate the meat through diffusion with the passage of time.

Salt first draws out the liquid from the meat by osmosis; then the brine is reabsorbed into the meat while breaking down muscle structures.

There are several types of marinating according to added solution ingredients. While alkaline marinade solutions contain phosphates, the acid solutions are prepared with organic acids or their salts.

Water-oil emulsions are the third type marinade solutions. The ingredients are used to enhance yield by increasing water content, to improve color, flavor and tenderness and to increase shelf-life in final product.

A general rule of marinade-to-meat ratio is one-half cup of marinade per pound of meat. Times vary depending on the type, cut and size of the meat. Denser meats can marinate for 24 hours or even longer.

Using a marinade is an easy way to impart rich flavor into inexpensive or tougher cuts of beef like flank, shank, and brisket. Salty marinades that use ingredients like soy sauce and miso paste can help meat stay moist, while ingredients like oil and sugar can help form delicious caramel crusts.
Marinating meat

Extruder-Texturized Product: Meat extenders

Meat is considered the highest quality protein source not only due to its nutritional characteristics but also for its appreciated taste.

The use of extenders in the elaboration of food products is on the rise because the latter presents the advantage of minimizing product cost and improving or at least maintaining nutritional and sensory qualities of the final products.

A meat extender is a mixture that substitutes a percentage of raw material present in the formula of a meat product for various reasons; one of which is cost reduction, facilitating the acquisition of quality food for populations with few resources.

Meat extenders are made from defatted soy flour and soy protein concentrate, extruded at low moisture contents (20–35%), whereas meat analogues are obtained by extrusion at high moisture contents (50–70%) of soy protein concentrate, soy protein isolate, legume proteins including common beans and peas, or wheat proteins.

Meat extenders have been extruded from some cottonseed protein products. In addition to the above-mentioned raw materials sources, sunflower, peanut, sesame, pea, and bean proteins have also been used in the extrusion process for texturization.

Protein levels, protein quality, oil levels, fiber levels, sugar levels, sugar types, and particle size are most important features for the selected raw materials.

Functional properties of extenders are those physical and chemical properties which affect the behavior of the ingredients in meat emulsions during processing, storage, preparation and consumption.

Extrusion processing destroys the enzymes present in soybeans, including a urease that reduces the shelf-life, a lipoxidase that causes off-flavors by oxidation of soya oil and also a trypsin inhibitor that reduces protein digestibility. This improves the acceptability, digestibility and shelf-life of the product.

Meat extenders are available in flaked form (more than 2 mm), in minced form (less than 2 mm), and in chunk form (15 to 20 mm), and they can absorb 2.5 to 5 times their original weight in water.
Extruder-Texturized Product: Meat extenders 

How to braising meat?

Braising is a cooking method that often referred to as the “low and slow” approach to cooking large, tough cuts of meat or hard, fibrous vegetables.

Meats are browned first, both for color and to create a caramelized crust to seal in juices. The longer cooking time make braising the perfect technique for cooking inexpensive, tougher cuts of meat. Over time, the liquid helps transform tougher meats into tender cuts while maintaining flavor and moistness.

Five steps of braising meats
1. Season the joints and cuts of meat with salt and pepper.
2. Sear the meat by browning on all sides in a hot oven or in a pan on the stove.
3. Add and deglaze pan with braising liquid until ¾ of the way up to the meat.
4. Heat braising liquid until it boils.
5. Reduce heat, and simmer with the lid on until done.

Common braising liquids include stock or broth, wine, beer, coconut milk, cider or juice.

How to make sauce: Strain the braising liquid and cook it down by half to create sauce.
How to braising meat?

Spoilage of meat

Meat is a nutritious, protein-rich food which is highly perishable and has a short shelf-life unless preservation methods are used.

The causes of the loss of adequate qualities may be physical damage, chemical reactions, insect and rodent infestation and microbial growth. Spoilage is said to be a state of a particular food in which it is offensive to consumers' senses, usually caused by metabolites of contaminant microorganisms.

*Preslaughter handling of livestock and post-slaughter handling of meat play an important part in deterioration of meat quality. The glycogen content of animal muscles is reduced when the animal is exposed to pre-slaughter stress which changes the pH of the meat, to higher or lower levels, depending on the production level of lactic acid.

Higher levels of pH (6.4-6.8) result in Dark, Firm and Dry (DFD) meat. Long term stress causes DFD meat which has a shorter shelf life.

*Bacteria associated with meat spoilage produce unattractive odors and flavors, discoloration, gas and slime. Meat and meat products provide excellent growth media for a variety of microflora (bacteria, yeasts and molds) some of which are pathogens. The intestinal tract and the skin of the animal are the main sources of these microorganisms.

*Non-bacterial contamination plays an important role in hygienic properties of meat. Non-bacterial contamination includes chemical residues such as antibiotics, pesticides, hormones, heavy metals, radioactive fallout etc. meat may also be contaminated by grit, stones, pieces of metal glass, various inks, hair, paints, rust flakes, grease, wrapper etc.
Spoilage of meat

Fat composition in beef meat

Meat contributes a significant amount of fat to the human diet. Meat contains relatively high amounts of saturated fatty acids and ruminant meats are low in polyunsaturated.

The fatty acid content of different meats might be influenced by a wide variety of factors, including animal breed, external and internal fat levels, climate, and breeding, feeding and rearing conditions.

In general, lean meat contain about 5-10% of fat. In one study fat content in beef cut (semimembranosus) contain about 3.08% and 8.75% in biceps femoris.

Approximately half of the saturated fatty acid in both the lean and fat component of red meat is palmitic acid (16:0), and about a third is stearic acid (18:0).

The fatty acids in meat are located mainly in adipose tissue, commonly termed “fat.” This has a role in product quality, contributing toward texture (tenderness and mouthfeel) and juiciness in both fresh meat and meat products. The fatty acid primarily responsible for soft fat in Wagyu (Japan) and Hanwoo (Korea) cattle is oleic acid.

The softness/hardness of fat, which is greatly influenced by fatty acid composition, affects various properties such as the sliceability, and the stability of sausage emulsions.

Fat composition of beef or marbling. Both the amount of marbling and the concentration of monounsaturated fatty acids increase with time on feed in grain-fed and pasture-fed cattle, but much more dramatically in grain-fed cattle.

Polyunsaturated fatty acids range from 11% to 29% of total fatty acids. Pasture fed cattle is a better source of omega-3 fats than grain feed beef.
Fat composition in beef meat

Processed Meat

Meat is a nutrient-dense food with high nutritional value. Meat and meat products are an important source of a wide range of nutrients containing large quantities of available bio compounds and consumers have a great passion for its flavourful taste.

Processed meat refers to any meat that has been transformed through one or several of the following processes: smoking, fermentation, curing, salting, air-drying, heating, or other processes to enhance flavour or improve preservation. This includes ham, bacon, sausages, tinned meat, etc.

Normally processed meats are made from pork or beef, but may also include other red meats, poultry, offal, or meat by-products such as blood.

The beginning of meat processing is lost in antiquity but possibly began when primitive man first learned that salt is an effective preservative, and that cooking prolongs the keeping quality of fresh meat.

Ancient record shows that preservation of meat products by ancient Egyptians is done by salting and sun-drying. The early Romans people are credited with being the first to use ice and snow as a means of preserving food.

Ground beef is the most highly known example of a fresh processed meat product. Cured and processed meat products make up a large number of the processed meat items sold in the United States and Europe.

Processed meat has been associated to coronary heart disease. Studies in the last decade also provided an overwhelming support that high consumption of fresh red meat and processed meat are linked with an elevated risk of developing bowel cancer, especially colorectal carcinoma, as well as stomach, pancreas and prostate cancers.
Processed Meat

Meat sausage: Preparation for production

Sausage is a food product resulting from the assemblage of proper ingredient in the right proportion coupled with a structured design and controlled process. The quality of the product is always a reflection of the status of the raw materials and the process. Its taste, texture, tenderness and color are related to the ratio of fat to lean.

Fresh sausage is typically prepared from one or more kinds of meats. It may contain water (not exceeding 3 percent of the total ingredients in the product) and binders and extenders (for example, wheat flour and non-fat dry milk).

Good sausage begins with good meat. Beef, veal, pork, lamb, mutton, and poultry are all suitable for use in sausage. A majority of sausage products are prepared with pork and beef. Meat should be fresh, high quality, have the proper lean-to-fat ratio and have good binding qualities. The meat should be clean and not contaminated with bacteria or other microorganisms.

Other ingredients such as salt (addition to taste, extract some proteins from meat, enhances flavor, reduce microbiological spoilage and increases water holding), water ice (assist the process of mixing and help salt to solubilize meat proteins), curing agents (inhibit microbial growth, provide pink color and enhance flavor), spices (add flavor to the product) and binder (promote fat and moisture retention) and extender (reduce formulation costs).

The basic steps in sausage making are:
• Weighing/measuring the ingredients
• Grinding
• Stuffing/linking
• Smoking/cooking

Sausage making has become a unique blend of old procedures and new scientific, highly-mech-anized processes. Traditionally, sausage was formed into a symmetrical shape, but it now can be found in a variety of shapes and sizes to meet consumers’ needs.

Meat sausage: Preparation for production  

Lean meat

Lean meat means a 3-oz serving of cooked beef must have less than 10 grams of total fat, 4.5 grams or less of saturated fat, and less than 95 mg of cholesterol.

The big benefit of lean meats such as chicken, turkey, beef and lamb, is that they are rich in protein, omega-3 fatty acids, vitamin B12, niacin, zinc, and iron.

Lean meats are mostly low in fat and sodium. Lean meats are also sources of a range of endogenous antioxidants and other bioactive substances including taurine, carnitine, carnosine, ubiquinone, glutathione and creatine.

Substantial evidence from recent studies shows that lean red meat trimmed of visible fat does not raise total blood cholesterol and LDL-cholesterol levels.

The saturated fat content of lean red meat is less than 1.5g/100g lean red meat compared with more than 37g saturated fat/100g of visible fat from red meat. The main lipid in lean meat tissue is phospholipid which makes up the major portion of the cell membrane structure, and these are rich in polyunsaturated fat (PUFA), while the other main lipid in lean meat is triacylglycerol which in beef and lamb are enriched in saturated fat and monounsaturated fatty acids (MUFA).

Today, more than 65% of beef cuts sold at retail meet government standards for lean, and 17 of the top 25 most popular cuts sold at retail are lean. Among those cuts are perennially popular and widely consumed beef products like Sirloin Steak and Tenderloin.

Lean meat

Wagyu beef

Wagyu is the Japanese word for “Japanese cow”. Wagyu cattle are native to Japan and are prized for their extensively marbled meat. Wagyu requires twice feed of beef cattle in the United States and must achieve a minimum weight 600 kg at shipment compare with about 400 kg for US beef.

The wagyu get a high-concentrate grain diet, mostly corn and some soy. Wagyu beef is considered to be the highest quality and commands higher prices than other domestically produced an imported beef.

Meat from wagyu cows and heifers’ carries a premium price over steer in each grade. It is highly marble beef – up to 40 percent in some cuts – makes their meat wonderful flavorful and very rich. Enzymes called calpains, which break down and tenderize meat, are also particularly active in wagyu breeds.

The most famous is known as Kobe beef, an only a specific breed of cattle called Tajima-gyu, - born and grown in the prefecture that surround the city of Kobe.
Wagyu beef

Meat tenderness

The most important aspect of meat quality is its eating quality or overall eating satisfaction, being a function of the combined effects of tenderness, juiciness, and flavour. Meat tenderness is the most difficultly predicted trait, but it is very important to meat quality and consumer acceptance. Tenderness is based on ease of chewing that is contributed by many factors. Among them, the fibrous nature of muscle contributes to chewing resistance

The fact that many myofibrils are arranged in register across the muscle fibers leads to more strength for muscle and decreases muscle tenderness.

Variation in beef tenderness may be attributed to breed (genetic status), carcass composition, and environmental factors (chronological age, time on feed, implants and ante-mortem stress). The three factors that determine meat tenderness are background toughness, the toughening phase and the tenderization phase. While the toughening and tenderization phases take place during the post-mortem storage period, background toughness exists at the time of slaughter and does not change during the storage period.

The tenderization process is estimated to begin soon after slaughter (perhaps as soon as 3 h, but it is highly variable among individual carcasses).

Current evidence suggests that proteolysis of key myofibrillar proteins is the cause of meat tenderization. These proteins are involved in:
*Inter-myofibril linkages (e.g., desmin and vinculin),
*Intra-myofibril linkages (e.g., titin, nebulin, and possiblytroponin-T),
*Linking myofibrils to sarcolemma by costameres (e.g. vinculin and dystrophin), and
*The attachment of muscle cells to the basal lamina (e.g. laminin and fibronectin).

The function of these proteins is to maintain the structural integrity of myofibrils.
Meat tenderness

Actin in muscle tissue

Muscle tissue is primarily composed of only a few types of proteins, with myosin and action being the two most important types in cooking.

About two-thirds of the proteins in mammals are myofibrillar proteins. The amount of actin and myosin differs by animal types and region.

Actin is the second most abundant myofibrillar protein in the myofibrils of cardiac and skeletal muscles, composing approximately 20% of the total.

A monomeric actin molecule is a globular protein and is often referred to as G-actin. These globular monomer are then assembled into an actin filament, called F-actin.

The molecular weight of G-actin is approximately 42,000, the diameter of each G-actin misnomer is approximately 5.0 nm, and each thin filament in skeletal muscle contains approximately 400 molecules of actin.
Actin in muscle tissue

Sources of meat

Of the many foods obtained from the land, humans tend to prefer animal foods, mainly beef, pork, poultry and mutton as well as their by-products e.g. cheeses, milk and eggs.

With the exception of pigs, meat may be obtained from animals specifically raised for meat production, or from animals surplus to other requirements. Thus beef may be obtained either from specially raise animals, male and other surplus calves or cows at the end of their milk-producing career.

The most important sources of meat in the United States is cattle. Horses have not been an important source of meat, except during wars when meat shortages have occurred.

However, in Africa, Middle Eastern and some Asian countries, especially in arid and semi-arid regions, camel meat is regarded as a main source of animal protein that equals and in some cases surpasses other meats in commercial importance.

The term red meat refers to flesh from beef, pork, lamb and goat. The term white meat refers to meat from poultry like chicken and turkey.

A market exists for domestically produced game-type meats. These include buffalo, bear, elk, kangaroo and rabbit. They are usually expensive and selected mainly as gourmet items. The meat is generally tough and very “gamey”. In general, this type of meat is prepared in moist heat. Meat usually contains 20-35% protein (weight basis).

Meat and meat products can be important sources of vitamin B6, vitamin B12, iron, zinc and selenium. The fat content varies from below 1% to above 40%. The fatty acid composition also varies between species.
Sources of meat

What is meat tenderizer?

Meat tenderizers soften tough meat by breaking down collagen with enzymes. Most powdered tenderizers use the plant enzyme papain as the tenderizing agent.

Commercial meat tenderizers containing enzymes are available for consumers to use, but they are effective only on fairly thin cuts of meat because they penetrate to a depth of only ½ to 2 millimeters. In general tenderizers work on the surface of the meat.

Meat tenderizers contain enzymes that break down proteins of muscle, fibers and connective tissue. They are sprinkled on meat which as then pierced with a fork to drive the enzymes below the surface, where they hydrolyses cell proteins tissue where activated by the heat of preparation.

Meat tenderizers enzymes extracted from a number of plants, including papaya, pineapple fig, kiwi and ginger.

The enzymes act slowly at refrigerator or room temperature, and some five times faster between 60 and 70 °C, so nearly all the tenderizing action takes place during cooking.

Some of the best tenderizers for meats have an alcohol base as beer and hard coder. The fermentation chemical process gives these products the tenderizing quality.
What is meat tenderizer?

Cut of meat: brisket

The brisket, a large, flat, fatty cut of meat is the front portion of the beef breast that lies between the front legs and takes well to smoking, braising or poaching.

It was long a favorite of peasant cooks because it was considered rather undesirable and was therefore inexpensive.

Brisket is usually sold boneless and is very easy to carve, providing nice uniform slices. It is hard to beat for flavor and texture.

The brisket can purchased whole (10 to 15 pounds), or as the brisket first cut (the leaner portion is often called the flat), or as brisket front cut.

Brisket is the cut of choice Texas slow-smoked pit-cooked barbecue and is also the best cut for corned beef.
Cut of meat: brisket

Epimysium of muscle

The individual muscle cells are encased in collagenous tissue that can be subdivided into the portion that is intimate contact with the cell called the basement membrane and a more distal portion called endomysium.

A group of fascicle of muscle cells is surrounded by a more robust collagenous connective tissue network called the perimysium.

An anatomical muscle consists of group of fascicles and is surrounded by the epimysium. It is a thick layer of connective tissue around the entire muscle. It is through the epimysium that the main product of muscle (shortening) is coupled to bone via the myotendinous junction.

The epimysium is generally easily separated from the body of the muscle, whereas perimysium and endomysium are not practically separated from meat.

The epimysium is generally continuous with the tendons. In some cases, the epimysium may appear to extend into the body of the muscle.
Epimysium of muscle

Curing process of meat

It was the process of treating meat with rock salt that led to modern curing practices. There is evidence of meat preservation with salt as early as 3000 BC and it is clear that the Romans utilized rock salt for a variety of meat preservation treatments.

Curing is the process of preserving meat for future needs primarily with salt; a byproduct of the curing processes is the added flavor that curing imparts, especially when spices and herbs are used. Among cured meats that are available in the market, hot dogs, other sausages and frankfurter, salami, bologna, pepperoni as well as ham, bacon and corn beef.

Almost all meats have a high percentage of water which must be removed to prevent spoilage, and the application of slat to meat extracts most of this water. Salt is to act as a preservative and to impart the characteristic salty character. It also increases the water-holding capacity of protein and thus enhances water uptake.

At the same time, salt, as it invades the meat, produces an antibacterial action to prevent meat from spoiling.

Cured meats represent a large portion of the processed meat products consumed in North America.

These processed meats are attractive in their color, flavor, texture and are popular because they combine variety with convenience of relatively long shelf-life and storage stability.
Curing process of meat

Myofibrils of muscle fiber

Skeletal muscles vary in shape and size. The central portion of a whole muscle is called the belly. The belly comprises smaller compartments called fascicule.

Each fasciculus consists in turn of approximately 100 to 150 individual muscle fibers that range from 1 to 40 micrometers in length and 10 micrometers in dimeter.

A muscle fiber comprises a number of long, thin, cylindrical rods known as myofibrils, the essential contractile units of muscle, which are separated from one another by a highlight specialized network of tubules the sarcoplasmic reticulum.

The sarcoplasmic reticulum, a specialized organelle that’s stores and releases calcium, is an interconnecting network of tubules running parallel with and wrapped around the myofibrils.

The major significant of the sarcoplasmic reticulum is its ability to store, release and take up calcium and thereby control muscle contraction.

Myofibrils are bathed in an aqueous fluid (sarcoplasm), which is about 75-80% water and contains mitochondria, enzymes, glycogen, adenosine triphosphate, creatine, phosphate and myoglobin.

Myofibrils range in diameter from 1 to 2 micrometers. They are grouped in clusters and run the length of the muscle fiber. In turn each myofibril comprises long, thin strands of serially linked sarcomeres. Sarcomeres are the functional unit of a muscle.
Myofibrils of muscle fiber