The release rates of rebaudioside A from matrices prepared with an agglutinant and yerba mate powder are reported. These matrices were used to delay the release of rebaudioside A when added to yerba mate and consumed as an infusion. Three agglutinants (Arabic gum, tapioca starch and maltodextrin) were used at 5% and 10% concentrations in each matrix preparation. Experimental data of extraction rate were fitted to two models in order to describe the release of rebaudioside A with each extraction. The best results were obtained with a matrix containing 10% maltodextrin. Extraction rate of this matrix and the material currently used by industries (sweetened yerba mate twigs) were compared. (C) 2010 Elsevier Ltd. All rights reserved.