In the meat and poultry industries, it is critical that retail products maintain appearance, texture, flavor, color and nutritive value during shelf-life, that period of time between being packaged for sale and being used by the consumer. But an increasing amount of products are shipped to retail customers in case-ready packaging, often spending a considerable time on delivery trucks and in distribution centers. For these products, fresh, real and clean can be a challenge.
“Meat and poultry products provide a perfect environment for spoilage microbial growth due to their high moisture and neutral pH,” says David Meggs, director of sales, Purac America, Lincolnshire, Ill. “Often, traditional methods such as salting, smoking, fermenting and refrigerating are insufficient in meeting today’s shelf-life requirements.”
There is some overlap between ensuring safety, also known as controlling for pathogens, and simply ensuring shelf-life. Basically, shelf-life is the amount of time that passes before meat becomes unpalatable or unfit for human consumption or unappealing to the eye. Thus, packers seek out ingredients and technologies that prevent the growth of spoilage microorganisms as well as prevent discoloration.
It is important to note that growth of spoilage organisms renders the product organoleptically undesirable but not necessarily unsafe. Pathogens can cause illness, and in some cases fatalities. Pathogen growth is often undetectable by the human eye.
Clean-label plant extracts
Most case-ready raw meat and poultry, as well as ready-to-eat products, rely on some form of vacuum packaging to assist with extending shelf-life. In addition, suppliers offer a number of ingredients that assist with shelf-life extension. In recent years, the focus has been on clean-label ingredients.
Select plant-based extracts, most notably rosemary and green tea, are well recognized for their ability to conserve the appearance, taste and quality of raw and cooked meat products, both refrigerated and frozen. “These versatile, natural solutions are label-friendly alternatives to traditional tocopherols or conventional synthetic antioxidants commonly used in the industry,” says Courtney Schwartz, marketing communications specialist-food technologies, Kemin, Des Moines, Iowa. “These extracts were developed to exert flavoring and antioxidant properties, the latter for delaying oxidation and increasing shelf-life.”
Rosemary extract is a concentrated source of carnosic acid, a potent antioxidant that slows the development of oxidative rancidity in protein. Oxidative rancidity leads to off-flavor development and unattractive discoloration. Rosemary extracts are typically standardized by carnosic acid concentration, giving processors flexibility to formulate the most effective solution.
Green tea extract contains as much as 40 percent of the antioxidants classified as catechins, half of which are the highly effective epigallocatechin gallate (EGCG). Green tea extract also contains an array of other chemicals that work synergistically with EGCG, including gallic acid, carotenoids, tocopherols, ascorbic acid and minerals such as chromium, manganese, selenium and zinc.
Suppliers will often use carefully selected plant breeds to produce the most potent extracts. Depending on the application and the desired outcome, extracts are carefully blended into the most effective combination.
“Our sustainable and highly controlled crop production allows our customers to feel at ease knowing that they have a safe and consistent supply,” Schwartz says. “We grow rosemary like other companies grow corn or soybeans. We use conventional breeding processes that begin with the largest collection of rosemary germplasm in the industry. We conduct our own propagation, transplantation, growing and harvesting and then develop unique products tailored to the needs of the market. Our proprietary manufacturing process yields a highly refined, concentrated, homogeneous solution resulting in a more consistent product.
“We work closely with our strategic partners overseas to grow the green tea plants for extraction,” she adds.
At the molecular level, rosemary and green tea extracts have similar functionality. “Their active components exhibit chain-breaking antioxidant activity,” says Kristen Robbins, assistant R&D manager, food technologies, at Kemin. “The main difference is that green tea extract has a lower negative flavor contribution to the final product. Thus, using a lower level of rosemary extract in combination with green tea extract allows the manufacturer to increase the natural plant extract usage rate, often resulting in an extract blend that performs better than using rosemary alone.
“Poultry products benefit the most from using straight rosemary,” Robbins says. “Red meat will typically gain additional shelf-life from using the rosemary/green tea blend because the green tea is especially effective at delaying myoglobin oxidation and flavor loss during long-term frozen storage. Foods that are oil-in-water emulsions will also usually benefit from using the rosemary/green tea blends, whereas straight rosemary extract is best for water-in-oil emulsions and bulk oils.”
Rosemary and green tea extracts and blends of the two come in both dry and liquid forms. “The dry product excels in applications that require dispersion across a large surface area, such as ground and processed meats,” Robbins says. It can also be blended with seasonings and applied topically by either tumbling or through a batter, as in the case of breaded nuggets.
“The liquid form is more applicable for emulsions. We offer a liquid blend that is specifically formulated for use in enhanced meats,” Robbins says. “It offers quick dispersion in cold brines.” When applied via brine, the solution either gets injected into protein cuts or sprayed on topically.
Another interesting plant extract catching the attention of packers is licorice extract. “Our licorice extract is naturally high in antioxidative phenolic compounds, which break the chain of oxidation in a variety of foods, including meat and poultry,” says Nancy Stachiw, director-applications technology, ICL Performance Products LP, St. Louis. “With this ingredient, manufacturers can keep the nutritional value, color and flavor of food while also extending shelf-life and palatability.”
As mentioned, the shelf-life of meat and poultry is limited by the growth of spoilage bacteria and pathogens. Some ingredients are designed to address both types of microorganisms and other attributes that impact quality.
“We offer several label-friendly ingredients with multiple functionalities,” Meggs says. “They can increase shelf-life, enhance food safety and can enhance meat flavors. These ingredients are produced by the fermentation of corn or cane sugar with specifically selected food cultures, and are often standardized with vinegar.
“We also offer liquid and dry antimicrobial solutions for the natural market. Declared on ingredient statements simply as vinegar, they are quite effective at extending shelf-life and inhibiting the growth of pathogens such as Listeria monocytogenes,” Meggs says.
“We also offer an ingredient line based on sodium and potassium lactates that can extend the shelf-life by up to 100 percent. These ingredients function by lowering the water activity and disrupting bacterial metabolism, thereby reducing spoilage bacteria growth,” Meggs says. “They function in both fresh and cooked meat products. They also improve the overall quality of the meat by enhancing tenderness and juiciness. And here are some added bonuses. They can increase the salty taste of processed-meat products, allowing manufacturers to decrease actual sodium levels. They also enable producers to control purge and achieve higher yields, and improve the overall quality of the meat.”
Fresh meat owes its red color to the presence of myoglobin. “This color is an important quality characteristic for consumers,” Meggs says. “Lactates slow the degradation of myoglobin into metmyoglobin, improving color retention. This is most significant in fresh beef, where the use of lactates can preserve red meat color for up to three additional days.”
To answer the challenge of increased freight and packaging costs and their impacts on the supply chain, the company now offers high-concentration lactates as well as several powdered antimicrobial solutions. “Using new processing technologies, we are able to produce these ingredients with the highest assay possible,” Meggs says. “These patented technologies also result in the cleanest flavor profile for potassium lactates.”
Another multifunctional ingredient is based on sodium acetate, salt and sodium diacetate. “It is known for its low usage rate of 0.35 to 0.50 percent, depending on the application and processor’s needs,” says Deanna Hofing, director of technical sales, Van Hees Inc., Cary, NC. “The active components in our unique synergistic combination of ingredients extend the shelf-life of raw and fully cooked meat, poultry and fish by interfering with the metabolism and growth of spoilage and pathogenic bacteria. This is accomplished through the donation of ions, which creates a hostile environment for bacteria to grow. The resulting product has improved color retention and flavor stability, and is safeguarded against L. monocytogenes and Clostridium perfringens.
“The ingredient system is a dry, free-flowing powder and is completely soluble,” Hofing says. “It is added to the fresh meat via a brine solution applied by injection or tumbling. Additionally, it can be added directly to the comminuted meat used in the manufacture of hot dogs and sausages.”
There are many other shelf-life-extension ingredient options available to packers, with selection driven by labeling and shelf-life goals as well as regulatory limitations.
Donna Berry is a contributing editor from Chicago and owner of Dairy & Food Communications.