Stability and antioxidant activity of alkyresorcinols in breads enriched with hard and soft wheat brans

Alkylresorcinols (ARs) are phenolic lipids that are mostly found in rye and wheat brans. In this study, the stability of AR content and homologue composition of hard red wheat bran (HRWB) and soft red wheat bran (SRWB) were studied, using four different bread formulations. ARs in wheat bran samples were extracted with four different solvents whereas ARs in breads were extracted with hot 1-propanol and quantified using gas chromatography-mass spectrometry (GC/MS). The different formulas used in four bread trial were: A) 100% white flour (control breads), B) 30% wheat bran, C) 30% residue bran after AR extraction, and D) 30% wheat bran plus 2% crude AR extract. AR content in breads varied from 1.1 to 82.9 mg/100 g and showed that they were heat stable during baking. After 1 h cooling, all breads showed significantly different (P<0.05) inner temperature, height and weight compared to control bread. Furthermore, bread D showed a better height than breads B and C (P<0.05). The effects of baking on total phenolic content (TPC) and antioxidant activity were also determined. A positive correlation was observed between oxygen radical absorbance capacity (ORAC) and TPC (R-2=0.89). (C) 2013 Elsevier Ltd. All rights reserved.