Investigation of the edible film features of cherry and apricot tree resins and their use in food coating

In this study, suitability of cherry and apricot tree resins as an edible film material and their potential use in food coating were investigated. Elementel analysis was performed to determine some chemical contents of resins. Amounts of dry matter and total phenolic compounds, and antioxidant capasities of resins were also measured. The levels of moisture of resins were quite low but rich in terms of phenolic compounds, therefore their antioxidant capasities were determined as good. Thermal analysis of each resin film was done and their behaviors against heat and weight losses were determined. Based on that both resins films were stable up to 400 oC but they decay at higher degrees. Significant changes in the weight loss of resin films against heat were observed after 300 oC degree. Surface images of resin films were taken using an scanning electron microscopy (SEM). As a result, the resin films were observed having an homogene structure and smooth surface. Strawberry (Fragaria ananassa) and loquat (Eriobotrya japonica) fruits were coated with resin film solutions. These fruits were compared with uncoated fruits in terms of some sensory and microbiological properties. Differences between two films were also observed. Shelf life of fruits coated with cherry and apricot resin films were longer than uncoated ones. Films have been effective in preventing weight losses in coated fruits. In terms of microbiology, the highest total levels of bacteria, yeast-mould and coliforms were detected in the uncoated samples at the end of the storage. According to the sensory properties, films didn't cause change in the aroma of the fruits and they have improved the overall appearance characteristics. It was determined that the sample coated with the cherry resin film was the most liked sample. In conclusion, cherry and apricot resins were found to be quite suitable as an edible film coating material. In comparing two resin films, cherry resin film was found to be more effective than other.