Fabrication and characterization of edible films from acha (Digitalia Exilis) and iburu (Digitalia iburua) starches

Abstract

Some properties of biodegradable edible films developed from starches of acha (Digitalia exilis) and iburu (Digitalia iburua), with glycerol as plasticizer, were evaluated and compared. Scanning electron microscope revealed that acha starch film (ASF) had rougher surface with larger size spores. Both films showed similar crystallinity pattern made up of A-type pattern of cereal starch as backbone and process induced VH-crystals. FTIR spectroscopy revealed the traces of some non-starch components in the films matrices. Both films had near-equal thickness (≈0.02 mm). However, iburu starch film (ISF) exhibited higher density, swelling power, water solubility and mechanical resistant while ASF gave higher water vapor permeability. Both films maintained their integrity during water solubility testing period. ISF had significantly (p < .05) higher transparency (97.08%) while ASF had higher a* (−0.06) and b* (1.81) values. Films from the starches exhibited promising characteristics that could place them as good materials for different packaging requirements.