Influência de métodos de secagem sobre as características do extrato hidroalcoólico crioconcentrado de manjericão (Ocimum basilicum L.)

Abstract

This study aimed to evaluate the influence of different drying methods on the physicochemical properties of hydroalcoholic extracts of basil (Ocimum basilicum L.). The leaves were subjected to four different conditions: in natura, drying in an oven with air circulation, without air circulation and freeze-drying. After the treatments, extraction was performed by percolation with a hydroalcoholic solution (96 ° GL), and the extracts were subsequently concentrated by cryoconcentration in blocks, with separation of the liquid and solid phases by centrifugation. Analyses of moisture, pH, acidity, soluble solids, dry residue and color were performed in order to identify the variations caused by the different pretreatments. The results demonstrated that the type of drying significantly interferes with the quality of the extracts. Freeze-drying stood out for better preserving the visual and physicochemical characteristics of the plant, while thermal methods caused darkening, greater loss of mass and changes in parameters such as acidity and dry residue. Cryoconcentration proved to be efficient in increasing the levels of soluble solids, contributing to the concentration of compounds without causing significant losses. The data obtained reinforce the importance of choosing the appropriate drying method in the processing of aromatic and medicinal plants.