Vapor Heat Research Unit for Insect Quarantine Treatments

Abstract
A vapor heat facility was designed and constructed for use in research on heating fruits for insect quarantine treatments. Air was heated to temperatures between 40 and 50°C by direct addition of steam at atmospheric pressure, resulting in relative humidities near 100%. This conditioned air was circulated directly through spaces between fruits by making the fruit load an integral part of the airflow path. With this method, fruits were heated to temperatures lethal to fruit fly eggs or larvae in 3-4 h compared with previous vapor heat treatment periods of up to 14 h.