Definição de parâmetros para a secagem em camada de espuma (foam-mat drying) da folha do juá (ziziphus joazeiro mart.)

Abstract

The Caatinga is a biome rich in plant and animal diversity. Among the species of endemic plants, the species Ziziphus joazeiro Mart., belonging to the family Rhamnaceae, popularly known as juazeiro stands out. One of its main characteristics is the resistance to the prolonged droughts of the northeastern sertão, proportioning shade, and food for the man and the animals. It is a tall, thorny tree with leathery leaves, small flowers, and globose edible fruit. Both the leaves and the scrapings of the juazeiro barks are very used in the popular medicine, manufacture of soap, products of hygiene and aesthetics. However, leaves and scrapings of the barks have short longevity after being removed from the trees. An alternative for prolonged conservation is the drying process, which by reducing the water activity of a material decreases the microbial growth activity. Foam-mat drying is even more advantageous by transforming the material into a stable foam by incorporating air or other gas, by proportioning a larger exposure area to heated air, working at lower temperatures, and facilitating rehydration of the final product. This work aims to define parameters for the foam mat drying of juazeiro leaves under physicochemical aspect. The variables: stirring time and leaves concentration, had a direct influence on the drying process. The use of this drying method presented satisfactory and viable results for obtaining the powder of the juazeiro leaves.