This research presents a case study of applying a thermosyphon for energy conservation in a smoked fish sausage oven. An oven with the size of 1.5 m x 1.5 m x 1.7 m (width x length x height) was installed with a thermosyphon made up of 304 stainless steel (AISI 304) tubes with 25.4 mm ID to improve temperature distribution, decrease processing time and reduce LPG consumption. The lengths of the evaporator and condenser sections were 30 cm and 120 cm, respectively. Deionized water, deionized water mixed with silver nano particles and deionized water mixed with gold nano particles at the concentration of 0.5% (w/v) were used as working fluids at a filling ratio of 80% by evaporator section volume. The oven using deionized water mixed with silver nano particles as working fluid appeared to have uniform temperature distribution. Consequently, processing time and LPG consumption could be reduced by 10 min/unit and 1.8 kg/unit, respectively. The quality of color measurement and consideration of texture of the smoked fish sausages exceeded manufacturing standards. (C) 2010 Elsevier Ltd. All rights reserved.