Application of locust bean gum based film/coating for prolonging shelf life of Turkish delight (lokum)

Edible films/coatings can be defined as thin and edible coating materials which are generally applied to food surface or inside of it with different methods. Edible films/coatings are used in fruits and vegetables after harvest keeping color, acid, taste and flavor components and achieve consumer attractive products. For this reason, usage of polysaccharide, protein, lipid films/coatings and their composites are suggested. Various techniques such as dipping, spraying, casting and painting techniques are used for creating edible film/coating. In this study; edible films/coatings which are made from Locust Bean Gum (LBG) were used on different types of Turkish delights (lokum) to determine the effects of LBG on shelf life of these foods. Firstly, Locust Bean Gum (LBG) was isolated according to literatures. Sorbitol was used as plasticizer material in producing of films/coatings. The prepared film solutions were applied on 4 different types of Turkish delight (Turkish delight with hazelnut/walnut and sultan delight with hazelnut/walnut) samples. The coated samples were kept at temperature of 25 oC laboratory conditions. Shelf lives of LBG coated and uncoated samples were compared with each other. In this study; products packed traditional ways after LBG coating was completed. Additionally in this study; various analyzes were applied on both LBG-based film-coated and uncoated Turkish delight samples to determine some parameters such as pH, ash, total amount (%) of sugar and invert sugar, microbiological analyzes and sensory analysis. Furthermore, surface analyses of the samples which are obtained by drying the prepared films were performed by means of Scanning Electron Microscope (SEM), also structural analyses of its were performed by means of Fourier Transform Infrared spectroscopy (FT-IR). In addition, quality parameters of both LBG coated and uncoated samples were investigated whether appropriate to the Turkish Food Codex. Results of total aerobic mesophilic bacteria and total yeast/mold analysis, performed in range of 0-60 days on coated Turkish delight samples, were found appropriate to the Turkish Food Codex. On the other hand, these results of the uncoated samples were found to be higher than values specified in Turkish Food Codex. In addition, sensory analysis of film coated/uncoated Turkish delight samples were carried out for some subjects such as appearance, color, texture, flavor and overall liking with help of a group of panelists.