High-temperature-short-time thermal quarantine methods

In this paper, kinetic models are discussed with respect to their uses in d escribing the intrinsic thermal mortality of insect pests. A unique heating block system was used to obtain kinetic information for the thermal mortal ity of codling moth larvae. The kinetic data demonstrated the possibility t o develop high-temperature-short-time thermal treatments to control codling moth and reduce thermal impact on product quality. Equations are presented to evaluate cumulative effects of any time-temperature history on the ther mal mortality of target insect pests and on the quality of host materials. Computer simulation results demonstrated that the cumulative thermal effect s on product quality during the heating period in conventional hot air or h ot water treatments are much more important than the cooling period. Radio frequency (RF) heating or microwave heating is suggested as an alternative to reduce adverse thermal impact to treated commodities during the heating period. A case study is presented to demonstrate the effect of RF heating i n a high-temperature-she rt-time thermal treatment to control codling moth larvae in in-shell walnuts. (C) 2000 Elsevier Science B.V. All rights reser ved.