US Patent 8707861 Dry food pasteurization apparatus and method

An apparatus for pasteurizing a dry food product comprises an impingement chamber, a conveyor for conveying the dry food product through the impingement chamber; a heater and water supply assembly for generating heated, moist air, and a fan for circulating the heated, moist air through the impingement chamber and onto the dry food product. In operation, the moisture in the heated, moist air condenses on the surface of the dry food product and produces a heat of condensation which heats the surface of the dry food product. Moreover, this heat of condensation is sufficient to kill a percentage of any pathogenic microorganisms which may be present on the surface of the dry food product.