عنوان مقاله English
The aim of this work was to study the effect of adding gellan gum and glycerol to film-forming solution on physical and mechanical properties of whey protein/gellan gum emulsion films and to produce edible coatings from whey and gellan gum and determine its effect on storage life of apricot. Whey protein coatings were prepared by dispersing 10% protein in distilled water; and plasticized with glycerol(Gly). Also gellan gum was added at different levels(0, 0/2, 0/4 and 0/6gr).
Therefore apricots were dipped in this coatings solution for 1 minute at 20˚C and air dried. Coated fruits together with the uncoated fruits(control) were placed in open dishes and stored at 4˚C and 85% RH for 1 months. Weight loss, total soluble solid(TSS), titrable acidity, pH, skin color, flesh firmness and overall acceptability of coated apricots and control were measured weekly.
The result revealed that the weight loss and changes in the quality parameters were much lower in coated apricots as compared with those. Color changes were also studied using a Hunter lab colorimeter. Finally results showed that the applications of whey coating increased overall acceptability, quality and storage life of apricot, while decreased its weight loss during storage.
The emulsion films were evaluated for physical and mechanical properties. Increasing the level of gellan gum in the films led to increase in Modulus(EM) and Tensile Strength(TS) but increasing gum to 0/6gr made less increase in Modulus(EM) and Tensile Strength(TS). About Elongation(EL), was observed increase too but in films that produced with 0/4gr gum, there was a slight decrease.
کلیدواژهها English
