Utilization of Renewable Energy Sources for Drying Medicinal and Nutritional Plants in Panama

Abstract

This research study looked at the design, construction, running and evaluation of an artisanal processing plant or factory that included a solar oven to capture the thermal energy for drying medicinal and nutritional plants. The use of renewable resources, especially solar energy plus a minimum of technological equipment and attention to principles of quality, hygiene, and future sustainability, contributed to the success of this engineering project. The factory was located in the rural community of El Cacao, District of Capira, Province of Panama, Republic of Panama, Central America. An indirect solar oven represented the center of the operation of the factory. Tests with locally grown plants including oregano (Origanum vulgare), coriander (Coriandrum sativum), rosemary (Rosmarinus officinalis), balsamino or bitter melon (Momordica charantia) and lemongrass (Cymbopogon citrullus), were conducted to measure the heat transfer and conductivity from the oven to the drying room. We also conducted an organoleptic study with community members to assess dried lemongrass as tea vs. a commercial tea. Preliminary tests with medicinal plants showed the efficiency of the factory in drying with significantly lower times than those found in the literature, obtaining the recommended humidity percentages. In addition, the organoleptic features of the lemongrass tea were rated as with more acceptable features as compared with the commercial lemongrass tea. The preliminary findings reported here are promising and, from the reception from community members, it is expected that they will accept the products being developed for them. The goal is for this and similar communities to have better and more permanent access to their traditional nutritional and medicinal plants.