'Murtilla', 'mutilla' or 'murta' (Ugni molinae Turcz) is a native Chilean species that produces a small berry fruit with a special aroma and a high antioxidant capacity. It is consumed raw, as jams, juices, canned products, confectioneries and liquors. The short production season demand application of preservation processes in order to enjoy the sensory and nutritional properties of this fruits during the whole year. Freeze drying is the technology that allows keeping such attributes almost indistinguishable from the fresh fruit, as consumers demand, however the high cost of conventional freeze drying (at high vacuum) preclude the mass utilization of this technology. In the present study the optimum conditions for the operation of an atmospheric freeze dryer in a pulsed fluidized bed were determined. Applying a 23 experimental design the effect of infrared radiation application, freezing rate and temperature on moisture content, drying time, polyphenols content and antioxidant capacity of dried murtilla fruits were determined. Drying times were equivalent to those observed for conventional freeze drying and the product obtained kept most of its sensory attributes but equipment and energy costs are significantly reduced. Copyright © 2009, AIDIC Servizi S.r.l.