Blending two commonly used antibacterial treatments could help processing facilities take better control of Campylobacter and reduce the risk of food-borne illnesses, according to scientists.
Researchers at Colorado State University found that using a combination of peroxyacetic acid (PAA) and low-pH buffered sulfuric acid is significantly more effective at tackling Campylobacter than using either treatment alone.
And they said timing the treatment so it is used after birds are cut up means that reductions in bacterial load could last even longer than when compounds are used individually.
Speaking to Poultry Health Today, Keith Belk, PhD, head of the animal science department, said with no vaccines available to control Campylobacter on the farm, the current focus for tackling the pathogen has to be in processing.
While previous research has indicated that addressing the pathogen at the parts level offers the most success, Belk and his team wanted to identify the most effective tools and techniques processors can use to kill the bacteria.
In their most recent study, they set up laboratory-based trials in which they treated chicken wings with a buffered sulfuric acid, a PAA compound and a combination of the two. Each treatment was applied as a spray and a dip.
While PAA destroys the bacteria through oxidation, the low-pH buffered sulfuric acid kills the bacteria because it is highly acidic, Belk explained.
“We wanted to see if when you combine those technologies into the same compound…if you get an additive effect,” he said.
The results show that all three methods are extremely effective against Campylobacter, with immersion treatment being more effective than a spray.
However, the most effective treatment is the combination of the buffered sulfuric acid and PAA compound.
Adding another layer to the study, Belk then looked at what happens immediately after compounds are added and measured the parts again 24 hours later to see the longer-term impact of the treatment.
“[The reason we did this] is sometimes you can injure a bacterium, but not kill them. And so over a period of time they recover and they grow back,” he said.
“In this study it turned out that the combination treatment by far was the most effective after 24 hours. Significant reductions, both when the parts were immersed or when the compound was sprayed onto them. As much as 2 logarithm reductions starting from the initial inoculum level of 3 to 4 logarithms of bacteria.”
While combining the treatments is unlikely to be the only application that will work against Campylobacter, Belk said the results were “pretty exciting.”
“With the peroxyacetic acid in the industry…depending on where it’s used [it’s approved] as high as 2,000 parts per million. We’re applying it in this study [at] 500 to 550 parts per million,” he said.
“And we’re not acidifying using the buffered sulfuric acid to the level that we might use it if we were to just use the compound alone. We only went to a pH of 1.2, and so combining those two components was more economical for plants.
“I think this is a really good option for plants to consider, particularly as new equipment’s being developed to go along with these compounds for application purposes.”
