A Development and Evaluation of a Vertical Yam-Pounding Machine

A vertical yam pounding machine having a similar operational principle to the traditional method of pounding was developed. The machine consists of a shaft, pulleys, V-belts, bearings, an electric motor, a vertical pounder, a gear train and a pounding bowl. White yam was used to carry out a performance evaluation of the developed machine compared to a commercial yam pounder QASA® (LBQ041A, made in China) yam pounding machine and pounded yam from the traditional method of using mortar and pestle. It was observed that the traditional pounding operation, the developed and the QASA® yam pounding machines gave 89.73, 96.24 and 98.25% of well-pounded yam excluding lumps. However, the QASA® yam pounding machine is limited to a maximum of 4 kg mass of boiled yam. The average throughputs of the traditional pounding operation, the developed and the QASA® yam pounding machines were 20.3, 39.46 and 47.34 kg/h, while pounding times were 18 min, 10 min, and 5 min respectively. The developed machine had comparable quality with similar sensory scores with regards to the taste, aroma, stretchability, and mouldability to the one from the traditional method. It also had a comparative long-life span, and overall acceptability score and was preferred over the pounded yam produced by QASA® pounding machine.