Effect of blade rotational speeds on the performance of cassava milling machine

Abstract

Abstract Cassava (Manihot esculenta) is a food source of carbohydrates in Indonesia. Cassava flour is used as raw material for processed food products. A performance evaluation of the cassava milling machine has been carried out by varying the blade rotational speeds. There are three parameters related to machine performance and two parameters related to cassava flour. The machine performance parameters are capacity, electric power, and specific energy, while the cassava flour parameters are temperature and particle size distribution. The performance evaluation showed that the higher the blade rotational speeds, the higher the capacity and electrical power, at 8000 rpm the resulting capacity and electrical power are 465.5 kg/hour and 2418.8 W respectively. At the same blade rotational speeds, the lowest specific energy is also obtained, at 19,540.52 J/kg. In all variations of blade rotational speeds, there is an increase in temperature from cassava chips to cassava flour, an average of 2.7 °C. Meanwhile, the cassava flour particle size showed that in each variation of the blade rotational speed, the dominant flour size is 60-80 mesh. At a blade rotational speed of 8000 rpm, the cassava flour particle size of 60-80 mesh is the largest when compared to other blade rotational speeds at 45% of the cassava flour produced by flouring. Based on statistical analysis, by varying the blade rotational speeds, it is stated that there are no significant differences in the results of the performance parameters except for the flouring capacity parameter at blade rotational speeds of 8000 rpm.