2.3. Extraction of crude phenolics of wheat
The crude phenolic compounds present in whole grains
and their milling fractions were extracted into 80% aqueous
ethanol (1:10, w/v) at 4 C for 16 h. The resulting slurries
were centrifuged at 4000g for 5 min and the supernatants
were collected. The residues were re-extracted (1:5, w/v;
80% ethanol) under the same conditions and supernatants
from both extractions were combined. The solvent was
removed under vacuum at 40 C and the resulting concentrated
slurries were lyophilized for 72 h at 47 C and
69 · 103 mbar. Yields of the crude phenolic extracts were
reported as percentage of defatted materials.