Abstract
The use of different protein sources in cereal products does not only aim to enrich them with proteins, but also to improve their protein quality, especially concerning the lysine content, the limiting amino acid in wheat flour. As an alternative to enrichment, protein isolates become viable because they provide protein content and quality. However, that the addition of protein sources to wheat flour greatly affects its rheological properties. Thus, the objective of this study was to evaluate the empirical rheology of wheat flour doughs substituted by pea (PPI), soybean (SPI), and whey (WPI) protein isolates, comparing the behavior of these three sources in order to predict the best application. Of all the isolates, PPI seems to have interfered less in the rheological profile of pure flour. WPI caused major changes, while SPI remained intermediate, but closer to PPI. Concentrations of PPI and SPI up to 10% and WPI up to 5% did not greatly modify the viscoelastic profile of the dough, which would allow the use of these mixtures in the production of breads, while higher concentrations would be more suitable for the manufacture of molded biscuits, in which the formation of a protein network is not necessary.
Keywords:
extensograph; farinograph; pea; soybean; whey