Effects of controlled germination on selected physicochemical and functional properties of whole-wheat flour and enhanced γ-aminobutyric acid accumulation by ultrasonication

- Soft white (SW), hard red spring (HRS), and hard white (HW) responded differently during controlled germination.
- Whole wheat flour of 5-15 h germinated wheat exhibited improved functional properties.
- Ultrasonication significantly enhanced γ-aminobutyric acid content in germinating wheat.
- Controlled germination produced wheat flours with improved functionality properties and nutrition value.

Using hard red spring (HRS), hard white (HW), and soft white (SW) wheat, this study examined how germination time affected the functionality of whole-wheat flour (WWF) and enhancement of γ-aminobutyric acid (GABA) content through ultrasonication. The falling number values significantly decreased and the glucose content increased by 227-357% after 15 h of controlled germination. The setback value of WWF paste decreased from 654 to 6 cP (HW), 690 to 9 cP (SW), and 698 to 7 cP (HRS), respectively, showing significant decreases of starch retrogradation in an aqueous system. The gluten quality and dough mixing performance of WWF after 5-15 h of controlled germination was enhanced since gluten is less weakened during the dough heating stage of Mixolab testing. After a 72 h germination, the GABA content increased by 339% of the non-sprouting counterpart. Furthermore, the GABA content in the ultrasound-treated SW sample was 30.7% higher than that without ultrasound treatment.