صدیقه یزدان پناه - Department of Food Science and Technology, Kazerun Branch, Islamic Azad University, Kazerun, Iran
شادی جوکار - Department of Food Science and Technology, Kazerun Branch, Islamic Azad University, Kazerun, Iran

Iran has long history at producing wide variety of dairy products.Doogh is one of the traditional Iranian drinks which is obtained by mixing yogurt with water and a little salt. And among the drinks presentin the market has special place.The main problem of dough during storage is its two phasethatresults from low pH and caseins accumulation.Preparation of dough which has not been serumSeparation, is considered by researchers and industry.The transglutaminase enzyme has positive effect on the serum storage capacity and the strength of the food in the gel by creating crosslinking at the proteins.Therefore, in the present study, the effect of using the transglutaminase and lipase enzyme was studied in order to improve the rheological properties and durability of the dough. The transglutaminase enzyme in doses of ۱۰, ۱۵ and ۲۰ ppm and lipase enzyme in doses of ۳۰, ۴۵ and ۶۰ ppm were added to doughs with fat ۱.۵% and ۳%and then, physicochemical, microbial, rheologyproperties, stability and microstructure were investigated. The results showed that treatment with these enzymes improved the stability. The treated samples has a particulate accumulation and casein clusters are more regular than the control sample. Added enzymes have changed the flow behavior of all treatments and their behavior led to a behavior non-Newtonian shear -thining. It also increased viscosity and decreased serum separationamount and two phase. This study showed that the combination of transglutaminase and lipase enzymes has a good potential for use in dough as a stabilizing and viscosity improvement factor.

Dough, Transglutaminase and Lipase Enzyme, Rheology, دوغ, آنزیم ترانس گلوتامینازو لیپاز, رئولوژی