Industrial-scale Radio Frequency Treatments for Insect Control in In-shell Walnuts

摘要: Prior to the 2005 ban, in-shell walnuts were routinely fumigated with methyl bromide for insect control before export. Several pilot scale radio frequency (RF) studies have been reported as a new technology completely most heat resistant insect, navel orangeworms, in in-shell walnuts without significant quality degradation. It is important transfer pilot-scale or laboratory research results large-scale industrial implementations. Heating uniformity one of most important considerations scaling up established treatment protocol for walnuts. Temperature variations after RF heating may result from different properties and non-uniform electromagnetic field. desirable determine a given unit and minimize effect walnut orientations positions by stirring during treatment. The required was achieved intermittent mixing at electrode gap 280 mm under hot air temperature around 60°C continuous process. The average kernel and surface temperatures 55°C treatments, respectively. efficacy treatments conducted using 25 kW, 27 MHz system conveyor belt speed 57m/h. The based on three replicates showed that 100% mortality fifth-instar orangeworms was an acceptable according standard peroxide, fatty acid colour values. If this method could be economically integrated into handling process, it would effective alternative fumigation disinfesting