Cooking shrinkage is an important quality factor in the production of burgers (Ammar, 2012). The diameter of the control sample used in this study was observed to shrink by approximately 16% during frying; however,this reduction in diameter significantly decreased with increasing amounts of Aloe vera added (Fig. 6) so that it reached to 2% in burgers
having 5% Aloe vera. Fat and water release as well as muscle protein denaturation are the main causes of the reducing diameter during cooking of beef burgers. Since the ability of burger extenders to form a gel and to retain moisture and fat determines the level of shrinkage in meat products (Alakali, Irtwange, & Mzer, 2010), the high moisture retention
of beef burgers containing 5% Aloe vera seems to have prevented the reduction in diameter.