At no other time has the topic of safety in salads generated more concern among consumers. According to MSNBC, the E. coli outbreak in spinach may cost the industry $100 million. Besides the considerable short-term costs, the long-term expenses of the outbreak are projected to be more significant than usual food safety incidents. However, there is another danger possible in deli salads that could produce a threat to consumers and the market for prepared salads: Listeria monocytogenes.
Key ingredients used in protecting food products are natural acids and their sodium/potassium derivatives (salts). Some of the most widely used of these in deli salads are lactic, acetic, sorbic and propionic acids. In order to help food developers make their best selection, PURAC has developed antimicrobial systems to enable the best balance of safety, flavor and pH control. PURAC® Fresh is a specialty ingredient blend that uses the advantages of lactic acid. Some characteristics include label-friendly ingredients, being effective over a broad pH range, providing optimum flavor enhancement, being affordable and efficient, and featuring supporting data for refrigerated and higher temperatures.
Besides having different antimicrobial properties, the various acids have significantly different flavor profiles. Lactic acid is mild and has a lingering taste. Malic acid is mild, and its flavor profile is less immediate. Citric and tartaric acids have sharp tastes. Acetic acid has a strong vinegar flavor. PURAC Fresh has a lower acid intensity in its flavor profile and a long-lasting effect.
PURAC Fresh also was researched for its effect in different salads, including chicken and potato, in a commercial laboratory using a commercial salad kit. Each of the salads was inoculated with a three-strain cocktail of Listeria. The trials were conducted at two separate temperatures: 40°F and 50°F, which represent the typical refrigeration and abuse temperatures over the shelflife of the products. The results were significant inhibition of the organisms tested. In another study, PURAC Fresh was shown to hamper common spoilage organisms, such as Lactobacillus and yeast.
On June 6, 2003, the USDA passed an interim final rule that allowed for three alternatives for ready-to-eat meat and poultry products. Each alternative subjects the company to different levels of sampling. Alternative 1 is a post-lethality treatment in order to reduce or eliminate microorganisms on a product. Alternative 2 allows for the use of an antimicrobial agent or process that can limit or suppress growth of L. monocytogenes. This alternative requires the least amount of testing and oversight by the USDA, and PURAC Fresh fits within this solution. Alternative 3 involves the use of sanitation measures alone and is subject to the most oversight.
PURAC Fresh is more label-friendly than the products of leading competitors, has a greater potential to remove preservatives and has the lowest cost-to-use profile. Currently, it is being used in all-natural products.