Organic acids were analyzed isocratically with Rezex ROA-
Organic Acid H+ (8%) (8 mm, 300
7.8 mm I.D. Phenomenex)
column. HPLC elution was carried out at 55 C using 0.005 N
sulfuric acid as the mobile phase at a
flow rate of 0.5 mL min1.
Organic acids were identified and quantified by using a UV detector
with wavelength set at 210 nm and by comparison of retention
times and peak areas with standard solutions of known organic
acids. The contents were expressed as mg 100 g1 of fresh weight.