Understanding organic acids
Organic acid salts are some of the most effective antimicrobial agents used in meat and poultry products. They are basically organic acids, such as propionic acid, acetic acid and citric acid, buffered, also known as neutralized, with a conjugate base.
Their mode of action on pathogenic and spoilage microorganisms is the same, but their effectiveness varies by the organic acid, specifically the amount of undissociated or non-ionized acid. It is the undissociated acid that can penetrate microbial cell walls. Once inside the microorganism, where the pH is near or above neutral, the acid dissociates, lowering the pH. With pH-sensitive microorganisms, including the pathogens and spoilage bacteria encountered in the meat and poultry processing and distribution environment, this change in pH impairs or stops growth. Further, the anionic parts of the organic acid, which are the negatively charged ions, that remain in the microorganism will accumulate, disrupting metabolic functions. This leads to an increase in osmotic pressure that destroys the microorganism.
Vinegar, a natural source of acetic acid, is now being used by processors as a label-friendly, all-natural antimicrobial. Many vinegar-based ingredients are simply labeled as vinegar on product labels.
“Vinegar is a time-tested, well-known ingredient,” said Courtney Schwartz, marketing manager for the food technologies division of Kemin, Des Moines, Iowa. “It is an ingredient found in grandma’s cupboard, which is what many consumers think of as clean label.”
Kemin developed buffered vinegar solutions that effectively inhibit Listeria in various meats. This includes enhanced pork loin, as well as ready-to-eat deli meats, hot dogs and other smoked and fresh sausages.
“Acetic acid is the key active ingredient in buffered vinegar,” Ms. Schwartz said. “We have sodium and no-sodium contributing varieties as well as a certified organic option. All are equally effective at inhibiting growth of pathogens and spoilage bacteria.
“Studies show that our buffered vinegar solutions have no negative effect on meat and poultry quality including parameters such as water-holding capacity, protein denaturation, color or flavor,” she said. “The ingredients are easily added via brines, marinades or spice blends as well as direct topical application.”
Acetic acid can be synthesized chemically or produced through natural fermentation. The latter has always been Kemin’s approach to manufacturing food-grade acetic acid.
“The natural fermentation process further contributes to the clean-label positioning of our buffered vinegar systems,” Ms. Schwartz said.
Corbion is vested in its proprietary natural fermentation technology that allows for the development of optimized-performance clean-label ingredients to replace chemical-sounding ingredients. These multifunctional ingredients are made from natural raw materials including organic acids, sugars and peptides, without artificial additives. They are approved by the U.S. Deparment of Agriculture for application in fresh and processed meat products and can be used in a wide range of products, including those with natural claims.
In ready-to-eat meats, some of these ingredients may be used to enhance safety by inhibiting the growth of Listeria for more than 100 days. Some ingredients may also inhibit spoilage organisms, increasing the shelf life of fresh meat, often times doubling it.
Corbion offers liquid and powder ingredients in a variety of formulations including no sodium and minimized taste. Depending on the ingredient, it is either labeled as “vinegar” or “cultured sugar and vinegar.”
To meet specific functional and sensory requirements, Corbion also offers natural systems that include ingredients with recognized functional properties. These include celery powder, citrus flour and jasmine tea extract. Such synergies allow for enhanced functionality combined with shelf life and safety.
“We have an all-natural, clean-label ingredient system based on fruit and spice extracts combined with dried vinegar,” said Chad Boeckman, director of marketing and national accounts, Wenda Ingredients, Naperville, Ill. “This blend has been proven effective against pathogenic bacteria as well as spoilage microorganisms and is declared on ingredient legends as ‘fruit and spice extracts, dried vinegar’ or ‘natural flavors, dried vinegar.’”
Less than a year ago, Newly Weds Foods introduced a clean-label ingredient for raw meat and poultry that protects against the three systemic failures leading to E. coli and Salmonella outbreaks. Based on a proprietary blend of vinegar and plant extracts, the ingredient inhibits pathogen proliferation throughout product processing and distribution, substantially reduces potential for cross-contamination and enhances E. coli and Salmonella susceptibility to heat.
“This new and revolutionary intervention gives processors, retailers, foodservice operators and consumers an added level of defense against these food safety concerns,” Mr. Maehler said. “It’s an easy-to-use liquid that can be applied directly to ground products and to whole muscle meats by marination. When incorporated into uncooked meat and poultry during processing, it inhibits E. coli and Salmonella growth known to occur in cold-chain distribution. It also provides protection against cross contamination throughout the distribution cycle and reduces pathogen survival rates even during a non-validated (home) cook. It does all this without any negative contribution to food flavor or overall product quality.”
World Technology Ingredients (W.T.I.) Inc., Jefferson, Ga., offers a range of clean-label and traditional antimicrobial ingredients. Not only do they inhibit the growth of pathogenic bacteria, as well as molds, yeasts and spoilage organisms, many of them have been shown to enhance the organoleptic properties of fresh and further-processed meats.
“Our ingredients are recognized as all natural by USDA,” said Klaus Kreuzner, director of sales at W.T.I. “The range includes vinegar in both a dried and liquid format. Both can be directly added, injected, tumbled, sprayed or incorporated into a variety of meat systems. A low-sodium version is also available.
“In addition, we have a liquid blend of lemon juice concentrate and vinegar,” he said. “It is ideal for ready-to-eat meats and is easy to use in marinades and brines.”
For manufacturers looking for cost-effective food safety ingredients, W.T.I. offers a patented granular, water-soluble blend of buffered sodium citrate or buffered potassium citrate. The latter assists with sodium reduction.
“These traditional functional ingredients improve product quality and safety, while increasing yield, stabilizing color and flavor, and reducing purge loss,” Mr. Kreuzner said. “Due to their superior ionic strength — almost twice that of salt — meat processors can increase water-holding capacity while reducing the amount of salt their recipes contain. At low use levels, both have been shown to inhibit Clostridium perfringens and Listeria monocytogenes in meat and poultry.”
The company conducted a study on fully cooked vacuum-packaged refrigerated roast beef comparing the effectiveness of the vinegar and vinegar with lemon juice ingredient to sodium citrate. The results showed that the two clean-label all-natural ingredients were just as effective as the traditional additive in controlling Listeria monocytogenes during 120 days of refrigerated shelf life.
Hawkins Inc., Roseville, Minn., is focused on the science of ensuring the safety of foods and improving the shelf life of meat and poultry. The company specializes in customized blends to meet the customer’s finished product goals.
“Our portfolio of food safety ingredients includes clean-label and traditional offerings,” said Fritz Wagner, business manager of food ingredients. “We have a new low-use antimicrobial line that is especially effective at controlling Listeria while cutting usage up to 50%.”When choosing a food safety ingredient system, it is essential that processors understand the limitations of their environment, as well as distribution requirements and consumer expectations. When these ingredients are coupled with proper product handling, processors are able to reap maximum benefit.