Document Type : Original
MSc, Department of Food Science and Technology, Faculty of Agriculture, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran.
Assistant Professor, Department of Food Science and Technology, Faculty of Agriculture, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran.
Associate professor, Department of Food Science and Technology, Faculty of Agriculture, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran.
Background and objective: Excessive intake of fatty foods is a risk factor in development of cardiovascular diseases. Use of fat substitutes in formulation of foods could decrease burden of the associated diseases. This work aimed to study the effect of tragacanth gum as a fat substitute on rheological, physicochemical, and sensory attributes of Mozzarella cheese.
Materials and methods: Tragacanth gum at concentration of 0.5, 1, 1.5, and 2% w/w and milk fat at concentration of 12, 14, 16, 18, and 20% w/w were used for cheese making. Sensory test was done by 5-point hedonic method. Rheological analysis was included to determination of storage modulus (G'), loss modulus (G''), cohesiveness, adhesiveness, elasticity, and tensility. Physicochemical characteristics were studied by determination of pH, fat, protein, moisture, dry matter, and melting point. All experiments were performed on days 1, 15, and 30 of storage on the samples stored at 4 °C.
Results and conclusion: By storing the treatments at 4°C, pH, moisture, cohesiveness, elasticity, and tensility decreased, while dry matter, melting point, fat, protein, and adhesiveness increased. Lower amounts of fat, dry matter, and protein were determined in the samples containing higher tragacanth gum. In comparison, moisture, melting point, cohesiveness, elasticity, adhesiveness, and tensility were increased in the samples formulated with higher gum. Viscoelastic behavior of the treatments was time-dependent, so that a linear behavior was observed up to 1000 sec for all treatments, followed by their logarithmic increase. Sensory evaluators preferred the sample containing 18% w/w milk fat and 0.5% w/w tragacanth gum. With respect to the nutritionists’ recommendation about consumption of low-fat dairies, the preferred Mozzarella cheese by its desired organoleptic and technical characteristics would be an appropriate choice for those seeking for healthy food basket.