Influence of different extraction processes for development of biodegradable films from residues of fruits and vegetables
Recently, edible films and coatings have attracted the attention of the food industry. Quality improvement, extension of shelf life and biodegradability are some of these advantages. An alternative for the production of those films is the utilization of vegetable raw materials from agro-industrial residues. Thus, this study evaluated the potential residues of fruits and vegetables in the preparation of films under different ways to extraction. The filmogenic solution (FS) was prepared by extracting 10% of the residue of fruits and vegetables wet (WR) and dried, as flour (RF) in different solvents: water solution (1), saline solution (pH 5.0 and 4.0) (2 and 3) and acid solutions pH 5.0 (4) and pH 1.0 (5), in a water bath (70°C/45 min). The films were obtained after drying (50°C/6h) of FS. No significant difference was observed in the compressibility of FS. It was found by the tensile strength (T) and elongation at break (E) that only the films 4 and 5 (RF) showed satisfactory mechanical properties, being T 0.031 ± 0.001 MPa and 0.022 ± 0.003 MPa, and E 6 33% ± 0.98 and 10.01 ± 1.72%, respectively. It was found that these parameters are dependent on the pH and the extraction method used. New tests in order to evaluate the chemical composition of the extracted compounds are being conducted. After extraction, some solutions became a consistent and difficult dehydration gel, showing a great potential for use as a coating and are being evaluated for possible use in minimally processed fruits and vegetables.