DOUGH PROFILING - AN INSTRUMENTAL METHOD FOR DOUGH STICKINESS MEASUREMENT

Dough profiling, an adaptation of Texture Profile Analysis, was used t o measure viscoelastic properties of doughs with varying degrees of st ickiness. Results were compared to sensory stickiness scores to determ ine the applicability of the dough profiling procedure as a stickiness evaluation method. Dough stickiness is a composite characteristic res ulting from the balance between adhesive and cohesive forces of a doug h. Adhesive and cohesive properties were not assessed separately. Ten flour and water model dough systems, representing an evenly distribute d series of stickiness levels from nonsticky to extremely sticky, as d etermined by sensory methods, were prepared from a standard bread whea t flour using increments of alpha-amylase or protease enzymes. Profili ng was performed on a Lloyd materials testing machine equipped with a size-adjustable profiling cell and using settings determined by respon se surface optimization. Twenty-four parameters were extracted from th e two compression, relaxation, and tension sections of the profiling c urve. All of the compression and tension parameters that were read dir ectly from the curves, except stringiness, had coefficients of variati on of <10%. Peak compression forces, average compression forces, tensi on work values for both cycles of the profile, and several relaxation parameter values were highly correlated with sensory stickiness scores (r greater than or equal to 0.95). The ten doughs could each be clear ly distinguished on plots of the first two canonical variables extract ed from the full set of profile parameters. Dough profiling is a promi sing technique for evaluation of dough stickiness.