| This study was conducted to develop and characterize edible films produced from lactic acid casein and either carnauba or candelilla wax. Films were produced by mixing lactic acid casein and sorbitol in distilled water at a pH of 10, then adding either melted carnauba or candelilla wax, followed by homogenization. Film microstructure was viewed using scanning electron microscopy, and differential scanning calorimetry was used to evaluate thermal properties of the films and film forming components. Water and oxygen barrier properties, as well as the mechanical properties of these films were evaluated over various wax contents and relative humidities.; Films were found to be continuous and homogeneous with an increasing separation of wax within the film structure as it's content increased. Films with candelilla wax incorporated were found to provide the best water barrier. However, water barrier properties of these films were still poor compared to synthetic polymers. These films provided a good oxygen barrier, and were found not to be affected by the incorporation of either carnauba or candelilla wax. Incorporation of wax increased tensile strength while decreasing elongation compared to films without wax, these properties also being lower than synthetic polymers. A good, but weak, heat seal was able to be made around the melt temperatures of lactic acid casein and sorbitol. |
