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Abstract: Edible films have been extensively studied with the aim to find an adequate formulation that allows improving food quality and safety. Both wettability and water-barrier properties are two important parameters that must be considered for an adequate design of edible coatings. The aim of this work was to measure the contact-angle of film solution based on carboxymethylcellulose (CMC) with murta leaf (Ugni molinae Turcz) extract to estimate the wettability on apple and quince skins and measure the water vapor permeability (WVP) of films. The results show that murta leaves extract did not affect the contact angle and wettability measured on the fruits surface. However, differences were obtained between apple and quince skin which can be explained because the dispersive component of surface tension of quince skin was lower than apple skin. The WVP was not affected by murta leaves extract incorporation. This allows concluding that the film properties assayed were not modified by the incorporation of murta leaves extract ecotype 14-4. [Copyright &y& Elsevier]

Abstract: The effect of murta (Ugni molinae Turcz) leaves extract on water vapor permeability (WVP) and gas permeability (GP) of carboxymethylcellulose (CMC)-based films was studied. Two ecotypes of murta leaves “Soloyo Grande” (SG) and “Soloyo Chico” (SC), were analyzed for their composition (HPLC-MS) and SC extract revealed a higher concentration of flavonols than the SG extract. The film forming solution was prepared with 2g of CMC, 0.4ml of glycerol and 0.5ml of sunflower oil in 100ml of water (Control), 50ml of water and 50ml of each exctract (SC50 or SG50) and 100ml of each extract (SC 100 or SG 100). The addition of murta leaves extract modified the WVP and GP of the films. The WVP decreased significantly (P⩽0.05) with the incorporation of SG extract in the film but not with the SC extract (P>0.05). The CO2 and O2 permeability of the films were influenced by the kind and concentration of murta leaves extract used. The CO2 permeability, with SG extract was higher than without extract (P⩽0.05) and with SC extract was not modified. The O2 permeability with murta leaves extract were lower than without extract. Therefore, it is possible to consider that films with SC acts only as barrier to the oxygen, but with SG the water vapor and gas barrier properties were modified, being more permeable to the CO2 and acting as barrier to O2 and water vapor. [Copyright &y& Elsevier]