Freeze survival characteristics of the mite, Tyrophagus communis (T. putrescentiae), a signficant pest of stored products

The mite, Tyrophagus communis (nee: mold mite, T. putrescentiae), is considered a global pest of stored food products, particularly those with a high content of fat, protein and moisture. Various methods of chemical controls have been employed in the past, including the fumigant methyl bromide and a variety of miticides. However, because of increased awareness for environmental and human safety, alternative methods are being pursued. One such method of product disinfestation involves subjecting the infestation to extreme low temperatures. This involves the freezing of infested product at a specific temperature over a given time that will be lethal to the mites. To determine an efficient protocol for low temperature disinfestation requires additional information on the freeze physiology of T. communis. We measured lower lethal temperature, lethal time over a series of temperatures, and the supercooling point of eggs, protonymphs and adults. These estimators are used to determine if this species is freeze-tolerant or freeze intolerant, as well as the minimal conditions required for substantial mortality of an infestation.