Moisture retention is critical to the quality of meat products for purposes other than just yield for cost savings. Moisture retention improves the eating quality at the consumer level. Mouths do not water over a dried roast beef or luncheon meats in which water has separated out in the package.
Consumers rarely have the time or ability to cook or reheat processed meats in a manner that will produce the optimal sensory experience; freezer burn, vacuum packaging and microwaves complicate matters. Even inexperienced chefs have a hard time getting meats to taste the way they should. “In the foodservice world, meat products are [regularly] abused,” says Tom Katen, a technical manager for meat applications at a starch company. “The forms of misuse are extensive, ranging from overcooked roasts and meats that are held too long in the warmer to meats that are frozen and thawed repeatedly.”
Bound and Battered
“Water bound to the meat protein will help maintain flavor, increase tenderness and make the final product more palatable,” explains Barbara Heidolph, market development manager at a phosphate supplier. During cooking, maintaining water-holding capacity is critical. If too much water is lost during cooking, the final product will end up tough and dry. The meat products in which water-holding capacity is the most important are generally hams, bacon and other deli products like turkey.Water-holding compounds help overcome this misuse. Salts, phosphates, modified food starches, low dextrose equivalent (DE) corn syrup solids, maltodextrins, gums like carrageenans, wheat, whey and soy protein isolates, concentrates and flours increase yield by binding water and some fat.
Such ingredients increase the end-user's cooked meat yields, reduce purge in long-term refrigerated, vacuum-packaged meats and thus reduce bacterial growth. In addition, freeze/thaw stability is enhanced with water-binding ingredients. “Water-holding compounds are particularly important for meat products that may encounter many freeze/thaw cycles,” says Heidolph.
Salt Solutions
Salt is the main ingredient used to impact yields. Sodium chloride extracts salt-soluble meat proteins and causes the myofibular proteins to unfold in its presence. Water and fat are then “trapped” or held in this matrix throughout processing and cooking cycles. “If the salt-soluble meat proteins are not extracted during processing, then there is a reduction in the overall water-holding capacity of the formula,” explains Katen.Since salt is pertinent to maximizing water-holding capacity, low-sodium applications require sodium chloride replacers, or a combination of water-holding compounds like vegetable proteins, gums and starches. “[In low-sodium formulations] a combination of ingredients can help offset the lack of water-holding capabilities,” says Katen.
Soy and whey proteins provide meat-like texture, while starches also supply water-binding ability and increased yield. Potassium chloride can maintain water retention, but sometimes at the expense of flavor. “Potassium chloride has been known to impart bitter/metallic off flavors,” informs Michelle Ludtke, a food scientist at a supplier of functional whey protein concentrates.
Potassium chloride functions the same as a sodium chloride in meat protein extraction. The sensory challenges of potassium chloride sometimes can be solved with masking agents, or sweeteners like trehalose, says Katen.
When potassium chloride is used instead of sodium chloride, the potassium ion aids in establishing ionic strength. “Often, before potassium chloride must be incorporated, the level of sodium can be reduced by using potassium functional alternatives, such as phosphates and lactates, along with reducing the level of sodium chloride,” says Heidolph.
Phosphate Family Reunions
Although sodium chloride is neutral and does not affect the pH of the system, sodium chloride increases ionic strength, lowering the isoelectric point. The isoelectric point is a pH where protein has equal amounts of positive and negative charges and does not readily bind water. For muscle protein, the isoelectric point is about pH 5. Like salts, phosphates increase ionic strength around the protein. Alkaline phosphates additionally increase pH and shift the protein away from its isoelectric point. These changes increase the muscle's water-holding capacity and reduce moisture loss during processing. For emulsion-type products, such as sausages or hot dogs, phosphates actually interact with the proteins to allow them to act as emulsifying agents, creating a stable water, fat and protein emulsion.“Phosphates are a wonderful ingredient in meats,” says Katen. When used at low levels (0.5% max.), they help prevent rancidity, solubilize meat proteins, improve juiciness and increase tenderness in meat.
“The selection of the phosphate is based upon a number of factors including pH of the product and the phosphate, level of fat, type of protein source, water hardness and level of sodium chloride,” says Heidolph. Sodium tripolyphosphate (STPP), sodium hexametaphosphate (SHMP), tetrasodium pyrophosphate (TSPP) and sodium acid pyrophosphate (SAPP) are among the more popular phosphates. “STPP is by far the workhorse of the industry,” remarks Heidolph. TSPP is used to increase yield because it is very alkaline.
Both SAPP and SHMP are used in specialty meat blends because of their pH and sequestration impact. They are acidic to neutral in pH. SHMP sequesters calcium, a mineral which can bind with proteins and reduce water-holding capacity. “SHMP is more capable of interacting with water hardness to allow for better interaction between the muscle protein and the phosphate,” says Heidolph. In some muscle-based products, such as poultry, color can also be a factor that may impact the selection and the amount of the phosphate to use.
Ham is a classic example of water retention in action. A ham's formulation is based upon pH adjustment, sequestration, ionic strength and protein/phosphate interaction.
Potassium polyphosphates can be used in reduced-sodium meat applications. “Additionally, since they are potassium-based, they provide potassium for which the USDA dietary guidelines encourage increased consumption,” says Heidolph. These potassium polyphosphates are designed to provide high solubility and clear solutions.
The higher the pH of the brine and, in turn, the final pH of the meat product, the more water binding will occur. Generally speaking, phosphates with a high pH (such as STPP or TSPP) favor higher yields, and phosphates with a low pH, such as SAPP, are used to impact cured color development. “Discoloration of meat tissue can occur when phosphate solution is not evenly distributed in the meat” says Jenny Zhou, a technical scientist in the meat group at a phosphate company. “Therefore, it is critical to ensure that phosphates added to aid in water-holding capacity are well-distributed in the muscle tissue.”
Pale, soft exudative meat (PSE), a condition prevalent in pork, is known to be associated with a rapid rate of glycolysis. Glycolysis converts the glucose to lactic acid which causes a decrease in muscle pH. Many reasons, such as poor animal handling and a delay in chilling pork carcasses, can contribute to the PSE condition. Products made with PSE muscle have higher cooking losses and lower juiciness and tenderness than normal muscle products. “Alkaline phosphates like STPP and TSPP are often used to improve the texture of the product that contains PSE meat,” says Zhou.
Phosphates should be designed to go into solution rapidly. “Most phosphates will not dissolve in a salt solution, so manufacturers should take care to dissolve phosphates in fresh water first,” says Zhou. “If the overall solubility of salt and phosphates is exceeded, precipitation will occur.”
Starch “in Crease”
“With consumers demanding convenience and food safety, the increase in fully cooked items is on the rise,” says Katen. “Increased cooking yields can off set the cooking costs.” A non-extended cooked chicken breast may taste very dry, but a 20% solution tumbled with a modified food starch would be juicy, tender and cost effective, he adds as an example.“A good rule of thumb when calculating the benefits of water-holding compounds is that modified starches hold five times their weight in water (some lab tests show 8%-10%); soy isolates can hold some five times; and semi-refined carrageenans will hold 25 times their weight in water,” says Katen. Each of these ingredients has different costs. To ascertain a “price per pound of water held,” divide the cost by the water-holding capacity.
Starches usually are the most cost effective water-holding compound in meats, opines Katen. Starches provide a non-protein base allergen, are freeze/thaw stable and consumer-friendly. “Although modified starches are bland in nature, if the level in the finished product is too high, it can taste 'corny or earthy,'” explains Katen. “As a rule of thumb, a good use level is less than 2.5% in the finished product. If starch is used with carrageenan, use two parts starch to one part carrageenan for the best combination of water holding and texture for cooked, processed deli meat items.”
Since amylose starch chains tend to retrograde or give up water after packaging, high-amylopectin starches, like waxy corn, are best used to achieve long-term water-holding capacity. Other common starch sources include potato, tapioca and wheat. “Potato starch has natural phosphate groups that love water, but it is very sensitive in processed meats with a higher salt content. Tapioca is used in extremely bland meat systems and is more expensive than the above starches.
Gums and Proteins
Since phosphates are more economical, it is not often that formulators would choose hydrocolloids over phosphates. Protein is more expensive than gums, so gums may be used as an extender or to change texture. However, some processors use a combination of these ingredients for optimal results.Hydrocolloids in the form of cellulose, alginates, carrageenan and many other gums act to bind water, reduce purge and extend meat. Hydrocolloids such as konjac form stable gels that set with heat in an alkaline system or in the presence of acid and salt. They form synergies with other water-holding compounds that provide for an abundance of textures that mimic meat.
In addition, custom blends of alginates and carrageenans provide absorption of marinades and suspension of insoluble ingredients that often are found in meat brines.
Functional whey protein concentrates can be used to increase yield and build viscosity in a wide range of meat products including whole muscle, coarse ground, emulsified, and chopped and formed meat.
“Water binding is especially noticeable in pre-cooked products that are re-heated,” says Ludtke. “Functional whey protein concentrate doesn't need heat to build viscosity. It binds water upfront upon hydration and imparts a very clean flavor that is complementary to meat. The level of addition is dependent upon the specific application and standards of identity.”
Acrobats and Needles
Meat products are injected or tumbled with the non-meat, water-holding compounds mentioned above. Generally, brine is injected into a product with the sole purpose of protein modification for water-holding capacity and tenderization. There may be some flavor (sugar, salt, spice) added. On the other hand, the primary purpose of a marinade is to deliver flavor (such as lemon garlic, mesquite, Asian, honey or barbeque) to a muscle or piece of meat. The phosphates aid in the rapid adsorption of the marinade and help to provide even penetration.A manufacturer chooses to inject instead of tumble a solution into a meat product because there are suspended ingredients that only stay on the surface of the meat item, while other ingredients dissolve into solution. “Injection allows all ingredients to be distributed more evenly within the whole muscle. For example, less tumble time and higher cooked yields are the advantages of an injected/tumbled chicken breast over a tumbled-only chicken breast.
When products are tumbled, they often are dependent on absorption of brines or marinades, which may not penetrate evenly or completely throughout the muscle piece. To improve tumbling, it often is done under vacuum atmosphere. Tumbling is more suited for chopped and formed meats to help with protein extraction in holding the pieces together, and for yield improvement in formed logs.
“For large meat pieces, most manufacturers use both: first injection and then tumbling to improve distribution,” says Zhou. Vacuum tumbling without injection is more popular with marinated poultry breast and chicken because the pieces are smaller and more irregular in shape and size. In comparison, ham requires injection.
“A mixture of phosphates, salts and other binders have been seen to work synergistically together to form a better product than any one ingredient on its own,” concludes Ludtke.
Sidebar: Marinade This
Challenges food formulators should keep in mind when formulating a meat product for water retention:
Source: Tom Katen (Cargill FPS), Barbara Heidolph (Astaris) and Michelle Ludtke (Grande Custom Ingredients).
Showcase: Starches and Hydrocolloid Gums
A starch offered by Cargill Food and Pharma Specialties is an economical water-holding compound for formulations for frankfurters, hot dogs and sausages. Polartex™ improves texture and reduces purge in formed meat and poultry such as meatballs and chicken nuggets. Manufacturers of formed fish and surimi products can use Polartex for enhanced product color and to improve water-holding properties and gel strength. It increases cook yields in pre-cooked items, as well as injected whole-muscle hams and turkey breasts, and helps increase juiciness in marinated products. Cargill Food and Pharma Specialties, Tom Katen, 877-650-7080, tom_katen@cargill.com.Indulgent products with high standards of stability are available for all fat, sugar and nutritional content categories. Main Street Ingredients has created a specialty line of Keystone™ stabilizers and base systems for non-dairy frozen desserts and novelties. The frozen dessert stabilizers and bases are easily processed using standard ice cream equipment and can be custom-engineered to your specifications. Main Street Ingredients, Michael Hengelsberg, Mike.h@msing.com, 800-359-2345, www.mainstreetingredients.com
The Satiagel LN series has been introduced specifically for the injection of white meat (chicken breast, etc.), when an entirely white color in the final product is required. A dosage level of 0.2% to 1.0% improves texture, sliceability and syneresis control. Degussa Food Ingredients' Satiagel LN series is applicable to all finished product needs, from strong gelling capacity for high injection levels to weak gelling capacity (but outstanding water retention properties) for low injection levels. Degussa Food Ingredients, Susan Gurkin, 770-986-6268, susan.gurkin@degussa.com, www.degussa-foodingredients.com
ORAFTI offers ground-breaking nutritional and functional properties with the soluble, all- natural fiber RAFTILINE® (inulin), RAFTILOSE® (oligofructose) and Synergy 1. Healthy benefits include improved calcium absorption, “invisible” fiber enrichment, improved mouthfeel and enhanced gastrointestinal health through prebiotics. RAFTILOSE and RAFTILINE replace fat and sugar in food, beverage and nutraceutical applications, without adversely affecting taste or mouthfeel. RAFTILOSE Synergy 1 offers enhanced calcium absorption at lower use levels. ORAFTI, Kathy Niness, 610-889-9828, KNiness@orafti-us.com, www.orafti.com
Other yield-enhancing products are part of the line of encapsulated ingredients that includes acidulants, antioxidants and salts offered to processed meat producers by Balchem Encapsulates. By encapsulating acidulants, MEATSHURE® has produced an amazing 30% to 40% gain in sausage production efficiency. Encapsulation allows the acidulants to be time-released, achieving the same effects in a short period of time that previously required a lengthy fermentation process. The ingredients deliver consistent acid levels, accelerated production speeds and reduced microbial growth to a broad range of processed meat manufacturers. The company offers off-the-shelf and highly customized ingredient solutions for consistent pH levels, microbial safety and shelflife improvements. Balchem Encapsulates, customer relations, 877-222-8811, bcpcustserv@balchem.com, www.balchem.com
Links
- FMC Biopolymer with information about hydrocolloid blends for extended meat
- The Ohio State University -- Meat Science department
- Reciprocal Meat Conference
- Grande Custom Ingredients provides information about whey increasing yield
- Focus magazines with information on phosphates
- Cargill Food Pharma Specialties, with information about phosphates
- Astaris LLC, a source of information about meat phosphate blends
- Innophos, a source of information about SHMP and STPP