The Influence of Transglutaminase Treatment on Physicochemical, Rheological and Organoleptical Attributes of Low-Fat Ultrafiltered Cheese Incorporated with Whey Proteins During Shelf Life

Ultrafiltered (UF) Iranian white cheese has the highest per capita consumption in Iran. Optimizing the formulation of transglutaminase -treated ultrafiltered milk makes it possible to develop a low-fat UF cheese with desired textural and sensory properties. However, persistence of active transglutaminase in cross-linking the cheese proteins during storage may adversely affect the product quality before it reaches the consumer. Thus, the present study aimed to monitor the changes in rheological and sensory properties of transglutaminase –treated low-fat UF cheese during shelf-life.
A control full-fat (16% fat), a control low-fat (5.95% fat) and an enzyme-treated low-fat (5.95% fat, 0.56 U transglutaminase/g protein, 8.79% retentate replacement with whey protein concentrate) ultrafiltered cheese were produced and their physicochemical, rheological and sensory properties were studied after 3, 20, 40 and 60 days.
Throughout the storage period, the lowest hardness parameters (fracture stress and Young’s, storage and lost moduli) belonged to the control full-fat sample, followed by the enzyme-treated and the control low-fat cheese samples. Hardness indices increased continuously during storage for all the samples among which the enzyme-treated cheese showed the highest rate of firming. This in turn led to significant difference (P Transglutaminase treatment of ultrafiltered milk results increase in hardness and thus decrease in texture desirability of the resultant low-fat cheese during storage.