|Hansen, James D|
|Tang, Juming - WA ST UNIV, BIOL SYST ENG|
|Wang, Shaojin - WA ST UNIV, BIOL SYS ENG|
Submitted to: Journal of Food Processing and Preservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 9, 2006
Publication Date: December 1, 2006
Citation: Hansen, J.D., Drake, S.R., Heidt, M.L., Watkins, M.A., Tang, J., Wang, S. 2006. Potential radio frequency-hot water dip treatment for postharvest codling moth control in fresh apples. Journal of Food Processing and Preservation 30:631-642. Interpretive Summary: Heat treatments are becoming the preferred method for disinfesting quarantine pests from fresh commodities intended for export. Hot water dips provide uniform heating, but may expose fruit surfaces to damaging temperatures for too long. A rapid method for heating is to use radio frequency energy, where heating is linear with time, very fast, can penetrate deep inside the commodity, and leaves no toxic residues. Combining these two methods would be advantageous by reducing treatment time. This study evaluates treatment efficacy against codling moth larvae in apples while measuring its affect on fruit quality.
Technical Abstract: A combination radio frequency-hot water dip method was examined as a potential quarantine treatment against fifth instars of the codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae), in apples, Malus sylvestris (L.) var. domestica (Borkh.) Mansf., intended for export to Japan. Apples were initially exposed to 27.12 MHz radio frequency energy at 12 kW for 2.75 min and then submerged in a range of hot water dips (49 to 51°C) for different durations. Efficacious tests were at 49°C for > 2 h, at 50°C for > 50 min, and at 51°C for > 40 min. Fruit quality tests indicated that the best hot water parameters were at 51°C for 40 min. Fruit quality was cultivar dependent. 'Fuji' apples tolerated heat treatment better than 'Delicious' and 'Gala' apples. Further testing is needed to refine the treatment to meet quarantine security standards and reduce quality losses of the fruits.