Effect of an enzyme preparation on wheat flour and dough color, mixing, and test baking

Bleaching flours with natural rather than chemical extracts is attractive because it reduces risks upon exposure and appeals to natural food consumers. This paper reports effects of a commercial proprietary blend of ‘natural’ bleaching enzymes on wheat flour and dough color, mixing behavior and test bake performance. Enzyme preparation did not improve whiteness (L*) and yellowness (b*) of flour system, but benzoyl peroxide sharply reduced b*. For whole wheat flour dough, L* increased for enzyme-treated dough after 2-h resting, ending higher than benzoyl peroxide and control dough. Yellowness increased in enzyme-treated dough. When enzyme application was during milling, resulting whole wheat flour dough had much higher L*. Mixograms of flours with increasing enzyme concentration showed severe dough weakness and rapid breakdown. Dialysis of the enzyme preparation in 3500 molecular weight cutoff (MWCO) tubes and freeze-drying prior to flour application recovered dough strength. l-cysteine in the enzyme mix was thought to adversely affect dough strength, and dialysis helped recover dough strength. However, pup loaf baking with dialyzed enzyme showed some loss of baking characteristics (loaf volume, loaf weight, and proof height) over the control. Although the natural enzyme extract addition enhanced whiteness for whole wheat dough, its effects on dough and baking properties were not favorable.