Effect of Process Variables on Efficiency and Particle Growth of <i>Spilanthes oleracea</i> Seeds Coating

The coating of vegetable seeds is a very common technique, mainly for the species which have small seeds. One of its functions is to increase the seed size to direct sowing. In the present study the coating of Spilanthes oleracea L. seeds with a polymeric suspension in fluidized bed was analyzed. The effects of process variables on the coating efficiency of top-spray fluidized bed coating were evaluated. The independent variables studied were the flow rate of coating suspension and the air mass flow. The quantification for the entrance variables influence on the coating efficiency and granule growth, as well as the identification of optimal conditions were made by means of an experiment factorial design technique. Polynomial models for the responses: efficiency and relative growth of the particles were deduced. The highest coating efficiency was achieved at a high flow rate of coating suspension.</jats:p