Effect of microbial transglutaminase on physicochemical properties of ostrich meat ball

The physicochemical properties of ostrich (Struthio camelus) meat ball added with different levels of microbial transglutaminase (MTGase) and subjected to heat at 40°C for 30 min (one step heating) or 40°C for 30 min followed by 80°C for 20 min (two step heating) were studied. The lowest cooking loss was found in one step heating sample added with 1% (w/w) MTGase. Breaking force of ostrich meat ball increased with the increasing of MTGase concentration (P 0.05). Addition of MTGase affected in decreasing of expressible moisture, especially in two step heating sample with 1% (w/w) MTGase addition. Two steps heating provided the highest whiteness value compared to that of one step heating process. Solubility of protein in ostrich meat balls were decreased with the increasing of MTGase concentrations. SDS-PAGE analysis revealed that the myosin heavy chain (MHC) content decreased and that the cross-linked protein amount, apparently increased with MTGase addition, especially in two step heating sample added with 0.7 and 1% (w/w). These results suggest that it is possible to improve physicochemical properties of protein gels by adding MTGase, thus increasing their potential utilization in mince based products.