Active and pH-sensitive nano-fillers were prepared from natural and modified montmorillonite (Mnt) and nanopackaged with anthocyanins extracted from the Jamaica (Hibiscus sabdariffa) flower. These were then used to reinforce corn (Zea mays) starchbased films plasticized with glycerol, and processed by extrusion and thermo-molding. Seven film systems were investigated for their potential as Bactive and intelligent^(A&I) bionanocomposite films with improved properties. The thermal and mechanical properties of the bionanocomposite films obtained were enhanced largely due to the added modified clay nano-fillers, and the nanopackaging of the anthocyanins between the nano-clay layers. Unfortunately, however, the bionanocomposite films failed as A&I materials, despite the supposed effect of the nano-clays as protective nano-encapsulating materials for the active and pHsensitive compound (anthocyanins). The results obtained suggest that the exfoliation of the nano-fillers as a consequence of the shear forces inside the extruder led to the exposure of the anthocyanins during extrusion. Because of this, we consider the largescale development of A&I biodegradable films incorporating natural pigments very unlikely being processed by extrusion/ thermo-molding, since there are several significant processes involved in the techniques currently available in the food and polymer industries that leave the active and pH-sensitive compounds unprotected.

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