Purpose: To evaluate a novel universal rapid detection kit based on microbial ATP bioluminescence for screening commercial sterility compared to traditional methods including growth on agar and pH measurement.
Methods: A variety of twenty-one UHT or ESL beverages (n=2/beverage/microorganism tested) were inoculated with 10 to 100 CFU/container utilizing a panel of microorganisms including a combination of bacteria (gram positive, gram negative and lactic acid bacteria), yeast and molds as applicable. A negative control (uninoculated blank) and positive control (inoculated with ~1,000 CFU) were also included in each matrix (N=1,104 total samples). Inoculated beverage containers were pre-enriched at 30°C for up 48 and 72 hours for dairy beverages and juices or juice dairy combinations, respectively. After enrichment beverages were screened for commercial sterility utilizing standard methods agar (SMA) as a reference method, pH and a novel universal Microbial Luminescence System based on the detection of microbial ATP.
Results: Utilization of microbial ATP bioluminescence resulted in a rapid method to screen commercial sterility in UHT beverages. Sensitivity and specificity were 98 and 99%, respectively, compared to agar. The study demonstrated that the novel universal kit can detect the presence of microbial contamination > 48 hours sooner than the traditional agar method. The study also demonstrated that pH is not a reliable parameter to screen for commercial sterility as not all microorganism will modify the pH during pre-enrichment.
Significance: Microbial ATP bioluminescence can provide a rapid result to screen commercial sterility by significantly reducing time to product release and thus reducing inventory hold times.