Abstract: A forced air defrost tunnel apparatus and method are provided for accomplishing carefully controlled defrosting of large quantities of bulk frozen food, such as pork, beef, lamb, chicken and turkey in whole muscle form, as well as bacon bellies and fish. The principle support for and shape of the defrost tunnel is provided by a stack or train of stacks of frozen proteinaceous food boxes or bundles that alternate with support spacer racks. An air containment device, preferably consisting primarily of a tarp, is closely secured over the stack or train of stacks. A supply of high pressure air at a temperature greater than that of the frozen food is forced through the defrost tunnel and flows through passageways within the support spacer racks.