Design and construction of coffee roasting machine with rounding cylinder tube using electric heat source

Abstract

The purpose of this research is to design a rounding cylinder tube on a coffee roaster using an electric heating element that will be used to roast coffee. The roasting process also uses an electric motor to rotate the cylindrical drum so that the stirring process becomes even. The research was conducted using engineering methods including identification of problems, roasting machine design formulation, prototyping, functional testing, and performance testing. The data analysed are roasting capacity, roasting temperature and the need for electrical energy used. The results showed that the roasting capacity was 2.3 kg·h–1. The serving of coffee for dark roast maturity levels can be ended when the temperature has reached a temperature of 201 °C. The need for electrical energy in the heater for roasting arabica coffee beans with a maturity level of a dark roast for 1 hour 54 minutes obtained an average value of 3.4 kWh, with the need for electrical energy for roasting arabica coffee beans which is 1.35 kWh.