Protecting organic meats from deadly bacteria calls for developing new antimicrobial agents from natural sources
By Cathy Day
When Jeff Sindelar talks about the ingredients he’s working with, you’d think he was making juice. Not quite. He’s adding things like cranberry concentrate, cherry powder, lemon extract and celery powder to meat.
But Sindelar, a CALS professor of animal sciences and a UW–Extension meat specialist, is not adding them for flavor. He’s looking at ways to ensure that meat products labeled “organic” and “natural” are safe to eat.
Sales of organic and natural foods are booming, with double-digit percentage gains almost every year. As more and more food processors scramble to meet that demand, they’re encountering a special challenge. Because they must process these meats according to organic and natural label requirements, they are unable to use the vast majority of antimicrobial agents employed in standard meat processing.
“Most ingredients and technologies that serve as antimicrobials—ingredients that can improve safety by either suppressing, inhibiting or destroying any pathogenic bacteria—are not able to be used in products labeled ‘natural’ and ‘organic,’” Sindelar says.
The trick is to find alternative materials and processes that deliver safety—and also offer the look and flavor that consumers value.
Sindelar has identified some options. “A number of different natural-based organic acids offer a significant improvement to food safety,” says Sindelar, who is working in partnership with Kathy Glass, associate director of the CALS-based Food Research Institute. “We have tested a number of different ingredients such as cranberry concentrate, grape seed oil and tea tree extract.”
Some compounds from natural sources work as well as such standard preservatives as sodium nitrite, sodium lactate or sodium diacetate, to name a few. But it can take heavy doses of some natural ingredients to provide equivalent results—causing some undesirable side effects.
“Cranberry concentrate is a very effective natural antimicrobial,” says Sindelar. “But if you use the amount needed to significantly control the growth of bacteria, the meat turns cranberry red.”
Part of the researchers’ work involves “challenge testing”—adding pathogenic microbes to the meat to make sure that a given ingredient prevents the growth of bacteria throughout processing and storage. If substantial numbers of microbes grow, that ingredient is ruled out as being an effective natural antimicrobial.
Successful tests have already led to new products. Cherry powder combined with celery powder, for example, “is already being adopted by processors because of how effective these ingredients are in improving meat safety and quality,” notes Sindelar. And the search for other natural additives continues.
Both researchers are certain they’ll find success—particularly as they continue working in partnership with producers in the field.
“Collaborative research between the university and industry is essential to understand the synergistic effects of these ingredients—and to ensure the safety and quality of natural and organic meats,” says Glass.