The use of a simple empirical method for objective quantification of the stretchability of cheese on cooked pizza pies

An empirical, easy-to-use, tensile method for the objective quantification of stretch of molten cheese was developed. Shredded cheese was distributed uniformly at a fixed loading (0.25 g/cm(2)), on to a pizza base, pre-cut in half: After cooking in a thermostatically controlled electric fan oven at 280 degrees C for 4 min, the pizza pie was placed on the platform unit of the stretch apparatus. The platform unit consisted of fixed and rolling elements. Before stretching, the pizza pie was clamped (one half to the fixed element and the other half to the rolling element). The rolling element was then drawn along the rail system at a fired speed, resulting in stretching of the molten cheese mass until complete failure of the extended string(s)/sheet connecting both halves of the pizza base. Stretch was defined as the distance travelled by the mobile element to the point of complete strand breakage. The stretch values obtained for low-moisture Mozzarella of different ages were influenced by cheese load and holding time before stretching of the cooked pizza pie, but were independent of stretching speed in the range 0.033-0.100 m/s. The stretchability of low-moisture Mozzarella cheese (2-17 weeks old) was greater than that of Cheddar cheese (2-25 weeks old). Analogue pizza-type cheeses, with compositions similar to that of low-moisture Mozzarella cheese, showed large inter-product variation in stretchability and generally had inferior stretch compared with low-moisture Mozzarella cheese. (C) 1997 Elsevier Science Limited.