Adding sourdough during industrial bread production.

Adding sourdough during industrial bread production influences the characteristics of doughs. The effects of sourdough on doughs are complex due to the wide variety of sourdoughs and the variables involved--type of starter cultures, dough yield, dough temperature and additives. It's necessary to understand dough behavior so that you can maintain the handling and machinability of the product. Acids and pH values impact dough properties. The influence of lactic and acetic acids on wheat doughs with and without added salt have been studied using an oscillation test on a controlled stress rheometer. The test included four mixing times and four rest times before the measurements were made. Phase angle, complex modulus and viscosity were measured for all doughs at selected rest and mixing times at frequencies ranging from 0.01 Hz to 10 Hz. The effects of mixing time were most visible immediately after the mixing was done. They disappeared partially during rest time. Doughs that contained acid but no salt showed the clearest characteristics of overmixing. Contact: Elke Arendt, University College Cork, Department of Food Technology, County Cork, Ireland; phone: [phone]; fax: [phone]; email: [e-mail].