MOLECULAR METHODS AS A TOOL TO SUPPORT FOOD SAFETY: CHARACTERIZATION OF THE MICROBIOTA AND DETECTION OF PATHOGENIC BACTERIA IN BLACK PEPPER

Abstract

Foodborne diseases represent an important cause of morbidity and mortality, hindering socioeconomic development worldwide. Detecting pathogenic bacteria in food is necessary for the prevention and control of outbreaks, thereby mitigating their impacts on public health. In vitro culture-based methods are sensitive for identifying these pathogens even when present at low counts; however, they are laborious and time-consuming. Food surveillance actions demand a short response time, which drives the development of faster analytical methods. This study aimed to characterize the microbiota and detect Salmonella in black pepper. Samples of black pepper collected from the northern region of Espírito Santo were subjected to metabarcoding for microbiota characterization and to qPCR for Salmonella detection. Samples that tested positive by qPCR were cultured for pathogen isolation and serotyping. A high diversity in the number of bacterial genera was observed in the samples. The use of PCR reduced the analysis time by five days and detected the pathogen in 30.5% (11/36) of the samples. The method proved sensitive, able to detect Salmonella at counts ranging from 0.004 MPN/g to >0.092 MPN/g. The evaluated techniques showed great potential for detecting the genus Salmonella and contributed to improving food safety. Metabarcoding showed low sensitivity for pathogen detection, and the applied methods used had limitations in species identification. The combination of molecular and traditional methods is still necessary to achieve a more complete and reliable risk assessment.