Coffee roaster design fits farmers’ choice

The end user has the final say on what type of product best suits his needs. This principle guided researchers Ruel M. Mojica of the Cavite State University (CvSU) and Jessie C. Elauria of the University of the Philippines Los Baños (UPLB) in developing a mechanical coffee roaster.

In designing the machine, the researchers conducted a survey among farmers in Indang, Cavite. Results show that the farmers prefer an electric-powered machine with automatic switch. This prompted Mojica and Elauria to fabricate and test an affordable, locally made mechanical crop roaster based on the criteria expressed by coffee farmers.

In a report submitted to the Philippine Council for Agriculture, Forestry and Natural Resources Research and Development (PCARRD), Mojica and Elauria explained that the developed mechanical roaster is advantageous over the existing machines in many ways. It is versatile, cost-effective, innovative, efficient, and market-driven.

The report states that the machine has a well-designed auger that makes roasting of other crops such as cacao and peanuts possible. Also, the auger is designed in such a way that movement of beans inside the roasting drum is uniform, thereby producing evenly roasted beans.

Further, the machine has a 10-kilogram capacity, just right for the needs of small-scale processors. And since it is made from locally available materials, farmers can buy it at an affordable price.

Mojica and Elauria emphasized that what makes the machine innovative is the addition of a microcontroller that displays the information needed to successfully complete the roast. The operator can set and see both time and temperature simultaneously. The degree of roast (light, medium, and dark) can be manipulated by simply setting the temperature. There is flexibility in controlling the final roasting results by increasing or decreasing roasting time. The microcontroller has a built-in sensor to check the temperature throughout the roasting cycle, hence over roasting is avoided.

Performance tests conducted by the researchers show that the optimum operating conditions for the mechanical roaster’s maximum response is at 204.5 oC roasting temperature, 19.75 minutes roasting time, and 12.25 percent moisture content (dry basis) of green beans.

Moreover, investment analysis showed positive results. Mojica and Elauria noted that the machine’s initial cost of P25,362.45 can be recovered in 0.52 year or approximately 186 days of continuous operation. Annual net income is computed at P51,744.32. To reach the break-even point, at least 1,219.45 kilogram of seeds should be roasted in a year. The benefit-cost ratio is 1.65, meaning for every peso spent for roaster use, gross return of 1.65 pesos is expected. Ofelia F. Domingo, S&T Media Service