PERANCANGAN DAN PEMBUATAN MESIN PENYANGRAI BIJI KOPI PORTABEL DENGAN MENGUNAKAN SISTEM PEMANAS GAS

Indonesia is one of the largest coffee producers in the world where coffee processing still done traditionally, so modern processing needed, especially in the roasting process plays an important role in determining the taste of coffee. This research aims to design, manufacture and testing coffee roasting machine with a capacity of 2 kg with modern and energy efficient. This research begins with optimim design of roaster drum using finite element method, analysis of temperature distribution on drum using Computational Fluid Dynamics (CDF), and designing the components of the coffee roasting machine according to need and applicable standards such as drum volume, drum material, shaft size, pully size and motor specifications. Based on analysis, dimension of the roaster drum is 200 mm in diameter, 350 mm in length with thickness of 2 mm. Material used for drum and shaft is stainless steel. After that, the coffee roasting machine was tested by varying the distance of the fire pit to 10, 15 and 20 mm, rotating drum speed to 60, 65 and 70 rpm and varying the type of coffee, namely Robusta and Arabica. The results of the design are dimensions, materials and designs that would be used in the manufacture of a coffee roasting machine with a capacity of 2 kg. In this test, to reach the temperature of 200oC distance of the stove fire pit used is 10 mm and the distance from the stove to the drum is 20 mm. The ideal drum rotation for testing coffee roasting machines is 60 rpm. This test produces a moisture content of 2.5% for robusta coffee and 2% for arabica coffee. The results of this study show that the lower the rotation during roasting, the lower the water content produced at each time variation