The effect of Tragacanth and Guar gums as edible coatings on the microbial, physicochemichal, rheological, and sensorial properties of Cheddar cheese during storage

The aim of this study was to evaluate a Guar/Tragacanth gum-based edible coating used on Cheddar cheese and the effect of these coatingson the microbial, physicochemichal, rheological, and sensorial properties of Cheddar Cheese During 90 days of period. Five coated Cheddar cheese were prepared in triplicate: coated with polyvinyl acetate as control (C), coated with 1% Guar gum (GG), coated with 0.75%, 1%, and 1.25% Tragacanth gum (TG1, TG2, and TG3 respectively). All samples were ripened at 8±2°C. Coating the Cheddar cheese with edible coatings in comparison with the control didnot significantly affect the growth of pseudomonas bacteria, and yeast (p>0.05). The total mesophilic aerobic bacteria (TMAB), and Coliform bacteria growth was significantly altered under the effect of edible coating materials (p<0.05). The lowest number of TMABs and the highest coliforms in the TG2 sample were observed. The pH, acidity, and melting point content of samples significantly affected with edible coating (P<0.05). The highest pH and acidity content in the TG2 and control samples were observed, respectively (p<0.05). The result of rheological analyze showed that the type of coating had a significant effect on Rheological factors (G/, G//, and ƞ*) in cheddar cheese (p<0.05). The lowest rheological factors (G/, G//, and ƞ*) in the TG2 sample, the highest G/ and G// in the TG3 sampleand the highest ƞ* in the GG sample were observed. Based on the sensory evaluation samples were not significantly different (p>0.05). On this basis, TG3 coating is recommended as an appropriate edible coating.