Lactates in Meat and Poultry Products

Lactates are sodium and potassium salts of lactic acid. These GRAS compounds have a neutral pH, a slightly salty taste and are naturally present in many meat products. They are hygroscopic and have bacteriostatic properties, as well. When used in meat and poultry products, lactates may enhance food safety, improve shelflife, help to stabilize color, increase flavor and improve production yields.  Perhaps the most important function in an era in which food safety is front and center is their ability to help inhibit microbial growth. Adding lactate to meat formulations adds an additional hurdle to the growth of potential food pathogens such as Listeria monocytogenes and food spoilage organisms. This, in turn, helps increase shelflife. Depending upon the concentration, lactates will inhibit the growth of Listeria, when compared to control samples without the ingredient.

The addition of lactate also will enhance product color. Browning is slowed when lactate is added, and it is inhibited even more when lactate is used in combination with acetates.

In meat systems, the bacteriostatic effect of lactates is a function of reduced water activity, the presence of undissociated acid ions and a feedback mechanism. Since the compounds are hygroscopic, they will absorb moisture, reducing the free water available to microorganisms. The mechanism of acidification through undissociated ions is a bit more complex.  What happens in this case is that once sodium lactate and lactic acid come into equilibrium, the undissociated acid can cross the cell wall and lower the internal pH of the organism. The cell must work to bring its internal pH back into equilibrium, so growth is inhibited. The feedback mechanism is caused by the presence of lactate or acetate outside the cell. The presence of these compounds at high levels inhibits transportation of by-products formed during its energy metabolism to outside the cell. The result is an inhibition of further energy production and growth.

The use of antimicrobial agents such as lactate is part of the USDA’s Food Safety and Inspection Service’s 2003 interim rule describing alternatives to control Listeria monocytogenes in ready-to-eat foods. Processors have the option of using: 1) A post-lethality treatment and an antimicrobial agent. 2) A post-lethality treatment or an antimicrobial agent. 3) Good sanitation.

According to PURAC, one of its ingredients for Listeria control enables processors to determine the growth rate of Listeria in relation to different growth parameters and set the proper use level of lactate and diacetate to control Listeria monocytogenes.  

The use of lactate in both fresh and ready-to-eat meat products can help minimize pathogen growth and reduce the potential for spoilage, thereby increasing food safety, shelflife and enhance flavor. Usage levels and delivery systems vary for the potential applications. Recommended levels in ready-to-eat products range from 2.0% to 3.3%, whereas use levels in fresh meat items are generally between 1.5% and 2.5%, depending on the application. The compounds may be mixed into the emulsion during blending (sausage products) or be injected into whole muscles as part of the brine. Working with the vendor to determine optimum usage levels that provide optimum antimicrobial activity and flavor profiles is the right path for a processor wishing to use lactate.

  

“Lactates in Meat and Poultry Products,” Rene Monderen, senior market development specialist, Purac America Inc., r.monderen@purac.com, www.purac.com

—Summary by Richard F. Stier, Contributing Editor



Carrageenan Solutions

Carrageenans are excellent binder systems that may be used in meat and other systems. They are extracted from a family of red seaweeds that have been harvested, cleaned and processed. During processing, the cellulose is removed by centrifugation and filtration, leaving a carrageenan solution. This is then concentrated by evaporation and dried.

In meat products, carrageenans may be used to enhance weight retention or product yields and to improve consistency, sliceability or spreadability of finished products. In addition, they can decrease the amount of purge, slicing loss and reduce loss from drip, while improving the potential for manufacturing high quality, low-fat products with better production economies.

Carrageenans are available in three different types: kappa, iota and lambda. Kappa produces stringy, very rigid gels, whereas iota yields softer gels. Formulating with different percentages of kappa and iota carrageenan will affect product performance. (See chart “Freeze/thaw Stability Provided by Carrageenans.”) As the graphic indicates, meat products formulated with iota carrageenan showed the lowest level of syneresis. Those with kappa carrageenan had the greatest.

Using carrageenan in combination with other gums such as locust bean or xanthan can produce a synergistic effect. In other words, it produces a system that enhances the capabilities of both ingredients. Gel systems using carrageenan and locust bean gum will result in reduced syneresis, enhanced elasticity and cohesiveness, and an ability to withstand higher temperatures.  These two gels must be heated to at least 80°C to ensure that the gels will dissolve.

When formulating with carrageenan, processors must consider the water chemistry at their facilities. If the water at a production facility is too hard, water-soluble carrageenan functionality will decrease significantly. For optimal functioning, water hardness levels should not exceed 60ppm.



“Carrageenan Solutions for Yield, Drip Loss, Improved Sliceability and Syneresis Control,” Rodger H. Jonas, national business manager– food, P.L. Thomas, rodger@plthomas.com, www.plthomas.com

—Summary by Richard F. Stier, Contributing Editor



Carrageenan in Meats and Poultry

Carrageenan gels are used in a wide range of industries including meat, dairy and other foodstuffs. Some 48% of all carrageenan used in the U.S. is used in meat processing and 36% in the dairy industry. Carrageenan is manufactured from dry seaweed, so it is a natural product, which is a valuable marketing tool in this day and age. Natural Grade Carrageenan (NGC) is acknowledged as a natural ingredient and may be used in delicatessen meats and whole cuts of meat. It reduces overall costs, improves texture, enhances slicing and improves operating efficiencies by reducing the potential for needle clogging.

Carrageenans are used in delicatessen meats such as turkey, ham, chicken roll and beef and in marinated products such as rotisserie chicken, case-ready raw marinated meats and whole smoked turkeys. For example, carrageenan manufacturers suggest that 40% pump be used for roast turkey breast. A brine consisting of 85.1% water, 1.7% trisodium phosphate, 5.7% salt, 5.7% dextrose and 1.8% carrageenan would yield a product with the following characteristics: reduced cook loss and package purge, improved texture and sliceability, a lower cost and fewer stretch marks. Pumping also reduced the cost of the product due to pickup and retention of water and brine. Similar benefits may be achieved by pumping whole chicken and other poultry.

It is recommended that carrageenans used in processing applications be low dusting and easily dispersible in brines. The dry carrageenans should be blended with salts and sugars that quickly dissolve in water. Salts that dissolve slowly such as phosphates should be dissolved gradually in cold water. The carrageenans should then be vigorously stirred in the cold brine to disperse them. When pumping, the brine tank should be subject to continuous agitation to ensure that the carrageenans remain properly dispersed.



“Carrageenan Types and Technology for Processed Meat and Poultry,” Scott Rangus, sales and marketing, Ingredient Solutions Inc., info@isinc.to, www.isinc.to

—Summary by Richard F. Stier, Contributing Editor



Transglutaminase: Information and Applications

Transglutaminase is an enzyme that forms cross-links between protein molecules, thus binding them together. This cross-linkage has unique effects on items such as protein properties, gelation capability, thermal stability and water-retention capacity.

The cross-links formed by transglutaminase strengthen the protein network structure in prepared meat products such as sausage and ham (both restructured and whole muscle), improving elasticity and firmness. It enhances slicing of delicatessen-style products, maintains or enhances texture, allows product development personnel to reduce salt and phosphates in products, allows the reduction of total meat content in formulated products and enhances texture in retorted meat products. For example, in a sausage, as the enzyme level in a formulation increases, the product’s breaking stress increases. This could allow a processor to more easily make claims for reduced sodium and/or reduced fat (see chart “Transglutaminase (TG) Level vs. Texture”).

With transglutaminase and proteins as a preparation, a processor can turn food pieces into consistently formed  portions. The system can add value to traditional cuts of meat and reform tenderized non-traditional cuts. The enzyme system may be added in the mixer at levels of 0.5% to 1.0% or used in tumblers at the same percentage. It also can be sprinkled on cuts of meat or added in a liquid slurry. Meat quality, condition of the meat (frozen, thawed or degree of thawing), temperature and reaction time all affect bonding. The system may be used for restructured block items such as kabobs and fajita strips, fish, shrimp and shellfish (e.g., scallops).

The microbial transglutaminase has a relatively wide range of application conditions. It is active over a fairly wide pH range and at pH values that are typical for many food systems. It is also active over a broad temperature range, even during the early stages of cooking. This temperature range makes it more versatile for use in processes where some of the conditions may be extreme.

The enzyme system may be used in all food products as “Generally Recognized as Safe (GRAS)” in the U.S. It should be labeled as “Enzyme” in the ingredients statement. Usage levels in processed meats and poultry is 65ppm, except for chicken breasts at 100ppm. The safety of the enzyme also has been approved by Health Canada. There are currently petitions pending for its use in meats, dairy and other products.



“Transglutaminase: Binding and Texture Modification of Muscle Foods,” Ajinomoto Food Ingredients LLC, www.ajiusafood.com

—Summary by Richard F. Stier, Contributing Editor



Using Fruit Fiber in Meats

Incorporating fruit fiber in meat products can yield unexpected nutritional benefits, including dietary fiber content as high as oat- and wheat-derived ingredients. They can either be neutral when it comes to taste or with typical fruit flavor. Finally, excellent technological properties can help a meat processor to improve quality or control costs. Fruit fibers from citrus and apple have the additional advantage of being plant cell wall materials, which are not classified to be allergens.

Fruit fiber is manufactured by drying and sieving insoluble plant cell wall materials available, for example, from juice production. Remaining sugars or flavor components can be further eliminated by additional washing steps; this also enhances the fiber’s dietary fiber content. The excellent water-binding properties are credited to the fiber’s sponge-like morphological structures as well as the balanced profile of insoluble and soluble dietary fiber.

For example, one commercially available citrus fiber has four to five times the water binding capacity as cellulose rich fiber from oat husks or wheat stems. An additional benefit of the fiber is its low caloric content and that it is readily dispersed in cold water. As the concentration of fruit fiber in water increases, the viscosity of the solution increases significantly. At about 5% the citrus fiber rehydrated in water has a paste-like consistency. In contrast to cereal-based ingredients with a rigid and dense surface, fruit fiber is very smooth. Processing by shear forces (as done during chopping) improves the rehydration process of the fiber, leading to increased water uptake and smoothness. This will mimic the mouthfeel of fats, allowing for the creation of reduced-fat meat products. Examples of reduced-fat products that could be produced using the citrus fiber are sausages, beef patties, teawurst and liverwurst. In both regular and reduced-fat meat products, a reduced syneresis enhances the quality and appearance, especially when stored under vacuum.

The good ability to bind water may also allow meat processors to reduce the salt content in their formulations (see chart “Shear Forces on Water Binding of a Fruit Fiber”). The citrus fiber can be even helpful in products with acidic ingredients like tomato pieces, which normally reduce the water binding of meat protein by lowering the pH-value. The citrus fiber products can help balance the water binding and maintain structural integrity. Beneficial effects can be achieved also in low-sodium products or phosphate-reduced products.



“Texturing Low-fat Processed Meat Products with Fruit Fiber,” Frank Mattes, president, Herbstreith & Fox Inc., usa@herbstreith-fox.com", www.herbstreith-fox.com

—Summary by Richard F. Stier, Contributing Editor



Phosphates Friendly in Meats

Phosphates are extremely valuable food ingredients used in a wide range of meat and poultry products. In processing operations, phosphates act synergistically with sodium chloride (salt). The addition of phosphates allows operators to reduce the amount of sodium used in formulations, and they also compensate for the oxidative effects of sodium chloride. Phosphates bind different proteins than salt, which enhances solubilization and hydration of proteins. Phosphates and salt also allow unbound myosin to form sols upon mixing and gels when heated. This helps to optimize water-holding capacity and reduce losses during cooking and cooling. Ultimately, use of phosphates will enhance the succulence of the final meat or poultry product.

Phosphates maintain the quality of both fresh and frozen seafood. Alone, they inhibit lipid oxidation (which detracts from the taste of the food), may accelerate the development of cure color, impart cryoprotection to native proteins (which means the food can be frozen and thawed without loss of product quality) and reduce moisture losses during freeze/thaw. Phosphate blends containing potassium will help compensate for diminished water-holding capacity in low-pH meats. Phosphates are also extremely valuable when it comes to maintaining seafood quality. They help minimize myofibrillar protein degradation, which can minimize post-mortem moisture loss. This helps to ensure compliance with meeting net stated weight.

Heat-processed seafood treated with alkaline phosphates has an elevated temperature at which protein denaturation occurs. This reduces the potential for over-cooking and losses during cooking and cooling. If used in heat-processed canned or pasteurized seafood (tuna or shrimp), phosphates can minimize the potential for struvite (a naturally occurring magnesium-based crystal that looks and acts like glass) formation by acting as a sequestrant. When used in previously frozen and/or spawning salmon to be canned, sodium tripolyphosphate can help retain sarcoplasmic protein within the cell, which minimizes the potential for the formation of a surface curd during the high and lengthy heat treatment of canning.

One of the most useful applications of phosphates is in the mechanical peeling of shrimp. Dipping shrimp in a solution of sodium tripolyphosphate (pH 9.5) allows reaction with collagen and improves the ability to separate the shell from the flesh. This aids the consumer by increasing shrimp meat yield without adding moisture.

Phosphates, a GRAS ingredient, also have the ability to soften water, bind metal ions that can act as pro-oxidants and enhance stability in atmospheric (non-vacuum) packaging applications.



“Phosphate vs. Phosphate-free Meat, Poultry and Seafood Applications; What Works and Why,” Lucina E. Lampila, food scientist, Prayon Inc., lucinalampila@prayoninc.com, prayoninc.com

—Summary by Richard F. Stier, Contributing Editor



Antimicrobials in Prepared Foods

Lactic acid bacteria are used in much commercial fermentation such as breads, dairy products and vegetables such as sauerkraut and meats. Lactic acid bacteria also produce a wide range of compounds that have antimicrobial activity. These include bacteriocins, which are peptides of various sizes and activity, organic acids and other molecules. Live bacterial cultures also have bacteriostatic or bacteriocidal activity against other organisms, including microorganisms of public health significance.

Bacteriocins produced by lactic acid bacteria have received a great deal of press recently. Among these compounds are nisin, lactococcins A, B, M, Ga and Gb, pediocin, leucocin and propionicin. Nisin is the most widely recognized of the bacteriocins. It is produced using selected strains of Lactobacillus lactis and is active against a wide range of Gram-positive bacteria. Pediocin has sparked interest in that it has good activity against Listeria spp. The ability of bacteriocins to inhibit microorganisms and preserve or protect foods is a function of moisture content, pH, temperature and concentration of the compound itself. Bacteriocins work to enhance shelflife through these barriers (see chart “Multiple Barriers”). As an example, bacteriocins can be more effective in products with reduced pH values.

Fermentates are the end result of actively growing cultures that have metabolized certain organic substrates. They consist of metabolites produced by the cultures, including any antimicrobial compounds. They are less refined and may be added to food products, where they may exhibit antimicrobial properties. Production of fermentates is less expensive than more highly refined bacteriocins.

Fermentates may be used in a range of products such as cottage cheese, salad dressings, sauces, dairy desserts and even mashed potatoes. When selecting a product for use, it is absolutely essential that the product development specialist understand the products and process operations in question. One must take into account whether the goal is pathogen control or microbial spoilage. One also needs to understand the microbial load of the food and what the target organism or organisms are. As an example, the addition of fermentate to a blue cheese salad dressing has been shown to be effective in controlling spoilage by yeast.  A product without any fermentate reached counts of 1,000,000/g within 12 weeks, whereas products formulated with 0.5% and 1.0% fermentate had yeast loads of approximately 1,000 and less than 100 after 16 weeks. Similar results may be seen with mashed potatoes inoculated with Bacillus cereus spores. Product with fermentate that was held at 8°C failed to reach a total load of 1,000,000/g in 70 days, whereas product without fermentate took approximately 25 days to reach that level.



“Antimicrobial Fermentate Applications in Ready-to-Eat Foods,” Larry R. Steenson, technical applications director, Danisco USA Inc., larry.steenson@danisco.com

—Summary by Richard F. Stier, Contributing Editor