Convergence angle of wheat dough in a zero length die

A mechanical system was designed, and constructed, to experimentally determ ine the angle of convergence (required to calculate extensional viscosity f rom converging flow data) of wheat flour dough flowing through a zero-lengt h die. To determine the convergence angle, and investigate potential dead s paces, tests were conducted with angled inserts. The mean angle for a flat- entry die was 43.1 degrees with a standard deviation of 5.30 degrees. Resul ts show that convergence patterns did not follow straight lines, and entran ce angles for wheat dough could nor be closely controlled with angled inser ts. Based on these findings, calculating extensional viscosity from converg ing die data cannot be expected to provide accurate values for wheat dough.