The U.S. Food and Drug Administration (FDA) has released findings from a sampling assignment that collected and tested processed avocado and guacamole from November 2017 to September 2019. The assignment sought to estimate the prevalence of Salmonella spp. and Listeria monocytogenes in processed avocado and guacamole as part of FDA’s ongoing effort to proactively ensure food safety and prevent contaminated food from reaching consumers.

During the assignment, FDA collected and tested a total of 887 samples of both domestic and imported processed avocado and guacamole. The agency detected Salmonella spp. in two samples, which were later determined to be distinct samples of the same brand of domestically manufactured guacamole. Neither of these samples had received high-pressure processing (HPP) treatment. HPP is a kill step increasingly used to neutralize harmful pathogens.

FDA detected L. monocytogenes in 15 samples. Of those 15 samples, eight had not received HPP treatment; the agency could not determine whether the other seven samples had received HPP treatment. Following whole genome sequencing conducted on the pathogens detected, the agency determined in the case of each positive that either there was no linkage to any clinical illnesses or that the available epidemiological information was inconclusive with respect to the food or other vehicle involved in the illnesses.

Whenever FDA detected a positive finding under this assignment, the agency sought to remove all affected product from the marketplace. This included refusing import shipments associated with positive product and adding two foreign firms to Import Alert 21-12, which informs FDA field staff that the agency has enough evidence or other information to allow for Detention Without Physical Examination of the specified products.

In addition to affirming that Salmonella spp. and L. monocytogenes may be present in processed avocado and/or guacamole, the assignment data show that the estimated prevalence of these pathogens in the non-HPP-treated samples was higher than in the HPP-treated samples. These findings appear to align with research that indicates HPP is an effective killstep. 

The findings of this assignment also underscore the need for processors of processed avocado and guacamole and others in the supply chain to comply with the agency’s Current Good Manufacturing Practice, Hazard Analysis, and Risk-Based Preventive Controls for Human Food rule, as applicable. FDA will continue to sample processed avocado and guacamole for pathogens, as warranted, to protect consumers.