DEVELOPMENT AND TESTING OF ARROWROOT (MARANTHA ARUNDINACEA L.) GRINDING MACHINE

An arrowroot grinding machine was developed and evaluated in terms of functional performance and cost effectiveness. The model consists of different component assembly parts such as transmission, rasper, crusher and base frame. It is powered by a 7.5 hp gasoline engine. Its salient features such as: 1) made of locally available food grade materials, 2) portable and 3)can be operated by a single person, give it the edge over other existing machines in attainingeffective processing. The model has an overall cost of P65,000.00.The effects of different factors which include the machine speed, tuber size and tuber maturityon the response variables such as power requirement, processing time, machine capacity andefficiency (percent starch recovery) were observed. RSReg and Response Surface Methodology(RSM) were used to determine the effect of the treatment factors and optimum performance ofthe machine; respectively. Experimental runs using Box and Behnken design with three level-incomplete factorial designs were conducted. Results revealed that change on the levels oftreatment factors significantly affect most of the response variables. Data obtained from theresponse variables mostly fit the linear and quadratic regression models.Results of evaluation revealed that the model i s capable of grinding arrowroot tubers withaverage power consumption of 0.85 kW, processing time of 7.85 minutes, capacity of 46.6kilograms per hour and efficiency (starch recovery) of 16.6%. Verification tests indicated thatthe actual values of responses were relatively close to the predicted values. Further, financialanalysis showed that the machine was economically feasible for small scale farm arrowrootproduction with payback period of 0.343 years or 4 months and 3 days, break-even point ofaround 350 kg per year and benefit cost ratio of 1.96.