Low-pressure treatment to control food-infesting pests (Tribolium castaneum, Sitophilus granarius) using a vacuum packing machine

Since recently, the food industry has been faced with serious problems regarding pest-infested food commodities and deregistration of many chemical biocides by the EU Biocide Directive. These conditions have created an urgent need for a physical method of protecting food against pests. Therefore, a vacuum packing machine was used for laboratory testing of the effectiveness of vacuum packaging on the mortality of the red flour beetle (Tribolium castaneum) and granary weevil (Sitophilus granarius) at different temperatures and exposure times. There were significant differences in the susceptibility to low pressure (vacuum) between the adult insects of both tested species: T. castaneum was approximately 10 times more susceptible to low pressure than S. granarius. A higher temperature significantly shortens the vacuum exposure time necessary to reach 100% mortality in the tested beetles under a constant low-pressure value (1 kPa). The lethal times (LT99) foradult T. castaneum were 15.1 h at 25°C and 30.8 h at 15°C. The lethal times (LT99) for adult S. granarius were 160.1 hours at 25°C and 274 h at 15°C.