Technical aspects of the production of dried extract of Maytenus ilicifolia leaves by jet spouted bed drying

This work presents an evaluation of the performance of jet spouted bed with inert particles for production of dried extracts of Maytenus ilicifolia leaves. The development of the extraction procedure was carried-out with the aid of three factors and three levels Box-Behnken design. The effects of the extraction variables, temperature (T-ext); stirring time (theta); and the ratio of the plant to solvent mass (m(p)/m(s)) on the extraction yield were investigated. The drying performance and product properties were evaluated through the measurement of the product size distribution, loss on drying (U-p), flavonoid degradation (D) and, process thermal efficiency (q). These parameters were measured as a function of the inlet temperature of the spouting gas (T-gi), the feed mass flow rate of the concentrated extract relative to mass flow rate of the spouting gas (W-s/W-g), the ratio between the feed flow rate of spouting gas relative to feed flow rate at a minimum spouting condition (Q/Q(ms)) and the static bed height (H-0). A powder product with a low degradation of active substances and good physical properties were obtained for selected operating conditions. These results indicate the feasibility of this drying equipment for the production of dried extracts of M. ilicifolia Martins ex Reiss leaves. (c) 2005 Elsevier B.V. All rights reserved.