Other antioxidants, including 4-hexylresorcinol, ascorbic acid and glutathione have been tested as a possible replacement for sulfites. Sulfites must be labeled because of their effect on the considerable portion of the population that suffers from asthma. Hexylresorcinol has been tested on fruits and vegetables, and is also used to control blackspot in fresh and frozen shrimp.
Bacterial control makes big strides
The battle against Listeria monocytogenes has given food science new tools in the quest for more shelf life. A variety of chemical additives can be added to hot dogs and deli meats to prevent recontamination of these products. Studies at the University of Florida found increased amounts of vitamin E in broiler feed increased antibody production in hens and pullets, protecting the birds against a variety of bacterial diseases.
"Supplementing turkey diets with vitamin E stimulates their immune responses, helping them clear the gut of the microorganisms such as Listeria that cause disease," reports Irene Wesley, a microbiologist for the USDA’s Animal Disease Center.
Careful handling is required when processing foods that require extra shelf life without the use of intensive processes that normally kill bacteria. A production manager at Vienna Foods, Chicago, a firm that elected not to use chemical preservatives in processing its hot dogs, suggests careful attention to temperatures, maintaining clean and sanitized surfaces, purchasing clean raw ingredients and carefully supervising the process.
Specific, accurate measurements of ingredients such as antioxidants is essential, as is complete blending with raw ingredients to ensure the antioxidants will be maximally effective. Some of these natural antioxidants are not heat stable, so they must be added during a cool phase of the process. Oil-based antioxidants, such as vitamin E, can be dispersed in small amounts of fats or oils.
There is a number of new and improved methods of shelf-life extension. The challenge to processors is balancing satisfying the needs of the specific product with the demands of a more aware and more informed consumer.
FDA asked to rescind carbon monoxide for meats
Just a month ago, the consumer media latched onto a brewing battle over a year-plus-old FDA decision to allow the use of carbon monoxide to keep packaged meat red and fresh-looking.
In July 2004, the FDA approved, allegedly without its own scientific review (relying on generally recognized as safe criteria), the petition by Pactiv Corp. and Precept Foods. Carbon monoxide replaces air to extend the shelf life of meat, but it also apparently reacts with the meat pigment myoglobin to create carboxymyoglobin, a red pigment that masks some of the natural aging and spoilage of meats, according to a petition filed late last year by Kalsec Inc., Kalamazoo, Mich.
When the Consumer Federation of America and other consumer groups joined the fray earlier this year, even local TV stations were airing reports on the practice. Nevertheless, Laura Tarantino, director of FDA’s Office of Food Additive Safety in the Center for Food Safety and Applied Nutrition, reaffirmed the agency’s decision in a Feb. 21 teleconference.