A Rapid Method for Separation and Quantitation of D‐Malic Acid in Fruit Juice

Abstract

A HPLC method using an aqueous mobile phase containing the chiral ligand-exchanger Cu II-L-valine complex at pH 5.5 with a polystyrene divinyl-benzene copolymer column was used to resolve D-malic acid in apple, pear, and Concord grape juices. D-malic acid was detected and quantitated at 330 nm in less than 15 min per sample. The detection limit appeared to be 2 mg/lOO mL D-ialic acid in 12 Brix juice, or 0.33% total malic acid in a typical apple juice containing 0.6 s/l00 mL using the described procedure.

Determination of organic acids in olive fruit by HPLC

“…Recently, there have been a great deal of research into the determination of organic acids in several fruits and fruit juices by HPLC method (Charles et al 1982;Eisele & Heuser 1990;Castaldo et al 1992;Wang et al 1993;Cámara et al 1994;Poyrazoğlu et al 2002;Shui & Leong 2002;Soyer et al 2003;Karadeniz 2004;Wu et al 2005). For example, Shui and Leong (2002) used HPLC with a diode-array detector at 215 nm for the determination of organic acids in fruit juices.…”