Cassava grating machine

By Ma. Teresa L. de Guzman
MediaCore, PCARRD

Research to improve processing of cassava roots into cassava grates is under way.   This involves development of a batch-type spinner for extracting water from fresh cassava grates and LPG-fueled rotary drum dryer.

The equipment will form part of an improved cassava grates processing system along with existing Philippine Root Crops (PhilRootcrops) grater.  The grater, with its cylindrical or circular blade made of punctured metal plates, transforms the fresh roots into grates at 100 kilograms per hour powered by a 1-horse power electric motor.

As intermediate product from cassava roots, cassava grates are used as ingredient in cassava cake, cookies, and “suman.”   Fresh cassava roots are grated, pressed or squeezed to remove excess water, and then dried.

A report from the Philippine Council for Agriculture, Forestry and Natural Resources Research and Development shows that current producers of grates, particularly in Leyte use batch-type or screw-type presser to remove water from the grates and then sun-dried. 

But the screw-type presser is laborious to operate and has production capacity of only 20 kilograms per hour.  The batch-type spinner, on the other hand, has a far larger capacity of 200 kilograms per hour.

Using the spinner type, processing costs P0.29 per kilogram of fresh cassava grates or almost four times cheaper than the P1.08 per kilogram cost using the manual presser.

In drying the grates, the rotary drum can do the job in 16 minutes or about 40 kilograms per hour.  With a consumption of 11-kilogram LPG tank in 22 hours, drying grates with rotary drum dryer costs P1.93 per kilogram.

Although cheaper at P1.36 per kilogram of grates, sun-drying results to lower quality product and the method requires bigger space.  It is dependent on weather conditions and takes about two consecutive sunny days to fully dry the grates.

The grates produced using the improved spinner and dryer smell and look good, indicating good product quality.  Engrs. Daniel Leslie Tan, Ramon Orias, and Roldan Piedraverde of Leyte State University–PhilRootcrops Research and Technology Center conduct the research.