The binding of model shortenings during mixing of mechanically developed bread doughs from fresh and stored flours

Abstract

Abstract and SummaryModel fats were prepared from defined binary mixtures of saturated and unsaturated triglycerides. Their effect on the volume of loaves prepared by the Chorleywood Bread Process (CBP), from fresh and storage‐deteriorated flour, was similar to that given by a good bakery shortening. The use of radioactively‐labeled glyceryl tripalmitate in fresh flour doughs enabled its distribution between ‘free’ and ‘bound’ lipid fractions of dough to be determined. Further studies which were made with the triglyceride of margaric acid, present only in trace amounts in wheat, showed that as the amount of saturated triglyceride added was increased, the amount entering the ‘bound’ fraction remained small and constant, whereas levels in the ‘free'lipid rose at similar rates in doughs made from fresh and stored flour. Evidence is given that ‘free’ rather than ‘bound’ saturated triglyceride is responsible for increasing the volume of CBP bread made from fresh flour. Unsaturated saturated triglyceride was ‘bound’ by stored flour doughs to a greater extent than by fresh flour doughs. A liquid saturated triglyceride could be used to replace the unsaturated triglyceride in a model fat. The poor effect of shortening on the baking properties of storage‐deteriorated flour could be overcome by adding more fat, either as such, or by increasing the level of its liquid constituent. Results are discussed in relation to the apparent requirement for hard fat in making bread by the CBP from fresh flour.