Lactic acid content was measured using a commercial
kit (F-kit D-lactic acid/L-lactic acid; Roche
Diagnostics, Basel, Switzerland). Organic acid
components were determined with high-pressure
liquid chromatography (SA-08A column) and a
ultraviolet 530nm detector.
16
Amino acid components
were determined with an amino acidanalyzer (835–50; Hitachi, Tokyo, Japan).