This study investigated the effect of breadmaking on the assay of phenolic acids from flour, dough, and bread fractions of three whole and refined wheat varieties. Comparison of the efficacy of two commonly used methods for hydrolysis and extraction of phenoilc acids showed that yields of total phenolic acids (TPA) were 5-17% higher among all varieties and flour types when samples were directly hydrolyzed in the presence of ascorbate and EDTA as compared to the method separating free, soluble conjugates and bound, insoluble phenolic acids. Ferulic acid (FA) was the predominant phenolic acid, accounting for means of 59 and 81% of TPA among all refined and whole wheat fractions, respectively. All phenolic acids measured were more abundant in whole wheat than in refined samples. Results indicated that the total quantified phenolic acids did not change significantly when breads were prepared from refined and whole wheat flour. Thus, the potential phytochemical health benefits of total phenolic acids appear to be preserved during bread baking.
Keywords: flour and two dough fractions; phenolic acids analysis; three bread fractions; two base hydrolysis and extraction methods; whole and refined wheat.