P2-185 Rapid Detection of Cronobacter spp. in Powdered Infant Formula Related Products, Raw Materials, and Environmental Samples Utilizing Loop Mediated Isothermal Amplification (LAMP) and Bioluminescence Detection Technologies

Tuesday, July 11, 2017
Exhibit Hall (Tampa Convention Center)
Christina Barnes , 3M Food Safety , St. Paul , MN
Neil Percy , 3M Food Safety , St. Paul , MN
Cynthia Zook , 3M Food Safety , St. Paul , MN
Lisa Monteroso , 3M Food Safety , St. Paul , MN
Gabriela Lopez Velasco , 3M Food Safety , St. Paul , MN
Introduction: For newborns and infants, Cronobacter spp. are opportunistic pathogens. Outbreaks associated to Cronobacter spp. have been linked to the consumption of powdered infant formula (PIF). Manufacturing environment, raw material, and final product for these pathogens are under strict surveillance by PIF manufacturers and health organizations to prevent illness.

Purpose: This study compared the performance of a LAMP-bioluminescence based method and the ISO 22964 (2006) standard for the detection of Cronobacter spp. from a variety of PIF manufacturing related products and environmental samples.

Methods: Inclusivity (106 Cronobacter spp. strains) and exclusivity (102 non-Cronobacter spp. strains) were assessed following AOAC guidelines. Method comparison was performed with 10-375 g portions of PIF (n=162), environmental samples (n=190), cereals (n=84), and raw materials (n=138) including mineral-vitamins, fatty acids, oils, flours, and probiotics. Samples were spiked with ≤ 5 CFU/portion of lyophilized Cronobacter spp. cultures. Portions were enriched with buffered peptone water ISO at 37±1°C for 18-24h. Detection was done by the LAMP-Bioluminescence assay. Enrichments were further confirmed following the ISO 22964 standard. The results from 10 g portions (n=319) were analyzed according to ISO 16140-2 and portions >10 g (n=255) were analyzed by Chi-square. Additionally, the probability of detection in 300 g portions and limit of detection were evaluated.

Results: Inclusivity and exclusivity were determined to be 100% for the LAMP-bioluminescence assay. Performance of the assay showed that there was no significant difference compared to the ISO-22964 standard. The LOD of the assay was 103CFU/mL in the enrichment and the lowest concentration detected was 1-2 CFU/300g portions.

Significance: The alternative LAMP-bioluminescence method offers a specific and rapid approach for the detection of Cronobacter spp., offering PIF manufacturers and commercial laboratories a next day result to evaluate the microbiological quality of these products.