Effect of solar drying on physical, chemical, and sensory properties of Cymbopogon citratus grown in Antioquia ‐ Colombia

Abstract

AbstractThis study aimed to evaluate the effect of solar drying on the physical, chemical, and sensory properties of lemongrass grown in Antioquia, Colombia. Two single‐factor experimental designs were used. The first one, evaluated the drying method: dryer with solar collector and ventilation cycle programmer (D2), African Drying Bed (ADB), and Traditional Drying (TD); with load of 7 kg/m2. The second experimental design evaluated different loads (7 kg/m2 and 10 kg/m2) in dryers D2 and D1. The following analysis were performed: drying time, moisture content, color, volatile compounds, and sensory. Drying times were 26.3 h for D2 and 30.2 h for D1. The drying time was higher in ADB and TD. There were no significant differences in a* for the samples D2 (−2.23) and D1 (−1.41), which had a lower loss of green color, indicating a lesser degradation of chlorophyll against ADB and TD. Geranial and neral were found in a higher amount, isogeranial and β‐myrcene were also identified. D2 and D1 presented a higher aromatic intensity with overall quality of 7.1 and 6.9, respectively (0–10 scale). With the use of the dryers inside the greenhouse, drying times were reduced, generating a product with better characteristics in color and sensory attributes.Practical applicationsAlmost all the seasoning and infusion industries in Colombia import the spices used as raw material in their products, even though with inferior quality from the sensory point of view, however, complying with other commercial criteria. The cost of dehydrated lemongrass imported in Colombia is higher when compared to other imported spices. Lemongrass grown in Antioquia, Colombia, presents some drawbacks in its postharvest processes, which makes its commercialization difficult at the national and international level. The results from this research show that using dryers with solar collector, fan, and ventilation cycle control; located inside the greenhouse solar dryer; it is possible to better control the drying process, obtaining competitive products at the industrial level, which could economically help producing families. Moreover, the times for drying are decreased and a product that meets the quality standards required by the industry in generated, overcoming those obtained from the traditional drying methods currently used.