tA responsive release system consisting of biocide encapsulated by the hydrophobic protein zein wasinvestigated, in which a biocide will be released if growth of micro-organisms occurs. Because biociderelease is difficult to detect, a model system using dyes with different size, polarity and charge wasdeveloped first to study the applicability of the zein matrix as an enzyme triggered responsive releasesystem. The responsive release efficiency was highest for dyes with a positive charge, that have limitedflexibility and the possibility of aromatic interactions with the matrix. The positively charged dyes showeda larger effect than negatively charged dyes. Additives were shown to enhance the release efficiency ofthe system. The most efficient release system combines the dye methyl violet with the additive oleic acid.These compounds interact to form a larger, more hydrophobic moiety. A plasticizing effect is thoughtalso to be important, since even without clear specific interactions between dye and additives, releaseproperties are enhanced. The charge of the additives seemed to be more important than their size, andboth hydrophobic and ionic interactions were shown to play a role.