Orchard Management Impacts On Food Safety Risk in Almond

Three outbreaks of salmonellosis have been traced to raw almonds from California. Orchard management practices over the last 10-20 years have been increasingly moving towards higher-density plantings with resulting higher canopy light interception. These practices lead to orchard floor temperatures that are both cooler and more consistent. In a heavily shaded almond planting in California’s San Joaquin Valley, where the majority of almonds are produced in California, orchard floor temperatures beneath the tree canopy are in a range where Salmonella is able to survive for longer periods.  Since almonds are shaken to the orchard floor, left to dry for 7-10 days, and then picked up by sweeping, there is potential for substantial mixing of the nuts with the orchard floor surface.  Additionally, almonds rewetted by irrigation water or rainfall release sugars that can support the multiplication of Salmonella either in the hull or when mixed with soil.  Orchard management practices, such as maintaining sufficient light hitting the orchard floor, and reducing the potential for wet almonds to remain in the orchard may reduce the risk of Salmonella survival or proliferation in almond orchard soils.