Progressive freeze-concentration was applied to Andes berry (Rubus glaucus Benth) pulp to observe changes in the volatile composition. The effective partition constant K, the water removed and a yield parameter defined as water removed per unit of time was used to adjust the performance of the apparatus. For freeze-concentration effectiveness, an enzymatic treatment of the pulp was found to be necessary. This treatment does not change the flavor and improves the volatile quantity, without producing changes in physicochemical properties of the final product. Freeze-concentration process preserves the flavor, with a total volatiles loss near 20%. Sensorial analyses show that progressive freeze-concentration process does not change the sensorial properties of Andes berry pulp. (c) 2004 Elsevier Ltd. All rights reserved.