Meat and poultry companies are constantly looking for ways to combine meat safety with shelf-life extension. And ingredient companies serving the industry are working hard to meet growing demands for such products.
"Antimicrobial blends allow customers to inhibit both foodborne pathogens and spoilage bacteria," says Shawnna Veasey, meat application technologist with PURAC America Inc., Lincolnshire, Ill. "In turn, processors are able to extend the shelf-life of their product."
Although PURAC’s roots are in the fresh-meat industry, the company has evolved to include an array of preservation applications for many meat and poultry products. "Today, our shelf-life extension projects include clean-label alternatives for ready-to-eat meat and poultry products, as well as enhancement for fresh meat and poultry industries," Veasey says.
When asked if there is a danger of extending shelf-life for meat and poultry products too far, Veasey responds, "It’s difficult to say because extending shelf-life ‘too far’ will never be reached. Meat and poultry are made up of amino acids, fats and enzymes that are eventually going to degrade and break down. Regardless of how many salts, spices and preservatives are added to meat, it will succumb to nature. Meat products are never going to be able to last decades or years."
The biggest challenge in extending shelf-life for meat and poultry products is trying to balance shelflife extension with product flavor, Veasey says. "As the concentration of non-meat ingredients increases so does the possibility for flavor impact," she adds. "Some products, such as uncured poultry, are more susceptible to off-flavors caused by non-meat ingredients. As such, the antimicrobial levels used in these products are less than in other RTE meat products. Hence, the resulting shelf-life is less."
PURAC’s most recent product line is called PuraQ Verdad, which consists of clean-label alternatives that aid in shelf-life extension and food safety. The PuraQ Verdad line contains three products, NV10, NV15 and NV55. NV10 is cultured corn sugar and is typically used for shelf-life extension of fresh-meat products. NV15 is also cultured
corn sugar but is blended with vinegar to provide Listeria control for cured RTE items. NV55 is a blend of cultured sugar and vinegar and is the most potent bacteriostatic ingredient in the PURAC product line. It can inhibit the growth of Listeria for 90-plus days in uncured turkey products. The company’s NV55 product does not have the same f lavor impact as other antimicrobial blends.
"I do believe there will be increased activity in shelf-life extension projects," Veasey says. "As global trade continues to grow, there is an increasing demand from overseas markets for U.S. meat and poultry products. In order to meet these demands, U.S. processors must increase product shelf-life, especially for refrigerated products."
Most current customers of World Technology Ingredients Inc., Jefferson, Ga., want the ability to promote extended shelf-life products, says Robert Brooks, former technical specialist for WTI. "As companies have grown their distribution, longer product shelf-life has become necessary to facilitate expanded logistics and storage requirements," he adds.
Brooks feels there is a danger of extending shelf-life too far. "In many cases, shelf-life analyses only consider microbial growth in the determination of a product’s stated shelf-life," he says. "However, enzymatic deterioration of the muscle or the development of rancid or off-flavors may significantly affect a product’s shelf-life, but may not be detected when only testing for microbial growth. Even if the product is still considered safe or wholesome, from a quality perspective, a processor’s objective must be to provide a product that is of the same quality near the end of its shelf-life as it was initially."
One major challenge for ingredient suppliers is maintaining pace with a moving target, Brooks says. "Bacteria are constantly evolving to adapt to their environment, and as such antimicrobial ingredients must evolve as well," he adds. "The bacteria that do not evolve are eliminated from the system, but are typically replaced by a more tolerant species."
WTI’s Ional Plus and Ional LC have proven their ability to stand the test of time, Brooks says. "These ingredients have provided processors the ability to extend shelf-life and food safety for nearly a decade," he adds. "The MOstatin line of products were added to provide processors of natural products a means of providing products with shelf-life similar to that of conventional products while maintaining a consumerfriendly label declaration."
Natural shelf-life extenders
Although BindMax Proteins, New Berlin, Wis., does not market ingredients specifically to extend shelflife, Rick Cassidy, vice president of product development, has developed all-natural shelf-life extenders made from salt and herbal extracts "that work," he says.
"Products that contain enough oregano oil, clove oil or garlic to kill bacteria, usually change the flavor profile of the meat product," he adds. "Also, it is extremely expensive to get university test data that verifies the effectiveness of the natural herbal blends."
For fresh, refrigerated meat and poultry products, the shelf-life critical control point is controlling microorganisms (e.g., bacteria, yeast, mold, etc.), Cassidy says. "The oldest and most common ingredient used is salt," he adds. "Salt can be used in conjunction with ingredients like sodium or potassium lactate, and sodium diacetate to control organisms like Listeria, E. Coli, Salmonella, Pseudomonas, etc. For cured meat products, sodium nitrite adds a secondary level of protection, especially for the deadly food poisoning caused by Clostridium botulinum."
Meat and poultry processors that comply with U.S. Dept. of Agriculture natural or organic product claims are not allowed to use lactates, diacetates or nitrites. Alternatives to these traditional ingredients include: apple-cider vinegar, lemon juice, oregano oil, rosemary extract, garlic, cultured-celery extract, green-tea extract and lacticacid starter cultures, along with either salt or sea salt to slow down bacterial growth.
Regarding frozen meat products, bacteria are not normally the limiting factor on shelf-life, Cassidy says. "Oxidative rancidity of fat usually limits shelf-life in a freezer," he adds. "Items like raw, frozen pork sausage contain salt, which has heavy-metal impurities that actually jump-starts oxidation of fat. Antioxidants like BHA, BHT, propyl gallate and citric acid are effective tools to slow down oxidation of fat. For the natural and organic products, rosemary extract, oregano extract and green-tea extract work great in uncured frozen meat products, and cultured-celery extract works well in cured frozen meat items."
Cassidy also believes it could be unsafe to extend shelf-life too long. "The stronger the ingredient is that kills bacteria, the greater the potential risk to the consumer," he adds. "It is like doctors who overuse antibiotics on patients. Someday when the patient gets really sick and needs an effective antibiotic, they will have built up a resistance to the antibiotic and it will not perform."
The biggest challenge for processors is to find shelf-life extending ingredients that are cheap, effective, safe and label-friendly, Cassidy continues.
Cassidy anticipates there will be several new ingredients derived from natural sources marketed in the future to improve shelf-life in meat and poultry. "Over time, consumers will seek less chemical preservatives and more natural alternatives, even if the shelf-life is shorter in some cases," he predicts.