Cassava starch films containing 25 and 50 % (in the polymer blend) of bovine gelatin were obtained using glycerol (30 %) as plasticizer. Film formulations were also obtained with 15 % of lipid (blend of fatty acid-glycerol esters). Microstructural and physical (optical, barrier and mechanical) properties were analysed in order to compare blend films with neat starch or gelatin films. The incorporation of gelatin and lipids to glycerol-plasticized cassava starch films notably affected their physical properties, while they showed polymer-phase separation and a lipid-dispersed phase. Gelatine incorporation gave rise to harder films with greater resistance to break and extensibility, while the lipids decreased film hardness and resistance but enhanced the stretchability, especially in films with 50 % gelatin content. Likewise, lipids improved water barrier properties of the films, but they impaired the oxygen permeability at the same time as they decreased the film gloss and transparency. After 5 weeks of storage, all the films became harder and more resistant to break, especially those which did not contain lipids, which enhanced the films' extensibility during storage. Cassava starch films with 50 % gelatine, both with and without lipids, exhibited very adequate properties for food coating or packaging.

The antimicrobial activity of essential oils (EO) is very well-known and it has been 13 reported that incorporating them into edible films based on biopolymers extends the 14 food's shelf-life. In this study, cinnamon, clove and oregano EO, at 25% with respect to 15 the polymer, were incorporated into glycerol plasticized starch-gelatin blend films (ratio

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The present work is based in a study starting from the behavior and characterization of films made from a 2% total solids (TS) dispersion of easy accessibility raw materials such as, cassava starch (Y), potato (P) and rice (A), combined with a protein i.e. gelatin (G) in a 50:50 ratio; adding guaiacum wood fiber of 75 and 150 µm (Ff and Fg respectively) until 1% (TS). Furthermore, glycerol was incorporated as plasticizer until 30% TS. The biodegradable films were elaborated by casting method. The films were characterized on the following parameters: thickness, water permeability and mechanical properties (Young modulus, tensile stress and elongation). It was found that the films made of AG-Ff and PG-Ff shown better barrier to the water vapor permeability with values of 2.5 and 2.4 (g. mm. KPa -1 . h -1 .m 2 ) respectively. The PG-Ff film showed, also, better mechanical properties i.e. higher Force, Young modulus and tensile stress increasing with time, with the lower elasticity; the YG-Ff and YG-Fg films reported the higher elasticity, being this parameter of interest, we will continue with this formulae to other manufacturing processes.

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This study evaluates the feasibility of using Achira´s leaves, plant native form Ecuador used by indigenous people for food cooking, as a raw material for the manufacture of disposable plates. For this purpose, the Achira´s leaf was coated with a dispersion made of rice starch and gelatin in a 50:50 ratio with 2% (w/w) of solids content adding to this matrix an antimicrobial agent. The used films, the uncoated and the coated leaves were analyzed for its moisture, thickness and mechanical properties, also, for its structure using X-ray diffraction and response for microbial attack In-vitro and In-vivo. Results suggested that the Achira´s laves are compatible with the active biodegradable coat used, due to a slight increment in the thickness of the leaves before and after application of the dispersion, additionally, the coating improves mechanical properties increasing the leaves elongation up to 40% which is desirable in materials subjected to process involving pressure and temperature. The X-ray diffraction valuessuggested that the matrix and the leaf may have a similar behavior in a thermoconforming process. Finally, the microbiological analysis performed suggested that the biodegrable active coating gives protection to the Achira´s leaves.

Este trabajo se hizo en frutas en Gamma IV, se presentó con dos alternativas de recubrimiento con 5% y 10% de ácido cítrico, incorporado a una matriz biodegradable de almidón de yuca y gelatina, incorporado por aspersión sobre rodajas de bananos y manzanas. Lo que se espera obtener es que se alargue el tiempo de vida útil, sin o con mínima presencia de oscurecimiento por acción de las polifenoxidasas. Los ensayos demostraron que el recubrimiento con 10% presento mejores propiedades de calidad y organolépticas.