Low-moisture products, including almonds, have been associated with outbreaks of salmonellosis. The U.S. FDA reported 168 cases of S.... Show moreLow-moisture products, including almonds, have been associated with outbreaks of salmonellosis. The U.S. FDA reported 168 cases of S. Enteriditis PT 30 associated with almonds in the U.S. and Canada in 2001 and another 47 cases in the U.S. in 2004. Current pasteurization methods use either heat or propylene oxide, which have the disadvantage of long treatment times and quality loss. This study investigated the use of fluidized bed atmospheric pressure plasma (APP) as a possible pasteurization method for the treatment of Salmonella Enteriidis PT 30 on almonds. Each almond sample was spot inoculated with 10 μL of inoculum. Almonds were placed in a fluidized bed APP treatment chamber fixed to an Enercon Dyne-A-Mite Variable Chemistry Plasma discharge that uses a mixture of clean, dry air at 90 L/min and an inert secondary gas such as Helium at 4 to 20 L/min. The gas mixture was energized using a high voltage (4.4 kV) power supply to generate electrons, gaseous ions, ozone and ultraviolet light. Treatment variables explored in this study were secondary gas type, Argon and Helium, flow rate, 4 and 14 L/min, and the time of treatment (0 to 60 s). Each trial was completed in triplicate. A 4 log reduction was achieved on average after a treatment time of 60 s and microbial destruction appeared to be linear in nature. Temperature measurement of almonds during plasma treatment and predicted lethality of Salmonella determined that heat alone was not a contributing factor to microbial reductions. These results highlight the potential of a fluidized bed APP to reduce treatment time and increase efficacy thus improving the predictability of destruction as compared to earlier research aimed at pasteurizing almonds with plasma. M.S. in Food Process Engineering, December 2012 Show less
Enabled Filters
(-) = NCFST / National Center for Food Safety and Technology
