Rapid and Simple Method for Determination of Target Organic Acids in Wine Using HPLC-DAD Analysis

A high-performance liquid chromatography method coupled to diode array detector (HPLC-DAD) was validated and applied for determination of targeted organic acids (tartaric, malic, shikimic, lactic, citric, and succinic) in Chardonnay and Merlot wines. Simple sample preparation was carried out, including only wine dilution with water and filtration before injection to the HPLC system. Separation of the analytes was performed with isocratic elution on a Shimadzu Shim-pack GIST C18 column (250 mm × 4 mm I.D., 5 μm particle size) with a mobile phase, an aqueous solution of H3PO4, with a concentration of 5·10−3 mol/L at pH 2.1 and flow rate of 1 mL/min. Monitoring of the acids was performed at 210 nm wavelength. The method provides values for the linearity (R2 > 0.998), limits of detection (0.00002 to 0.0025 g/L) and quantification (0.00006 to 0.0085 g/L), precision (RSD < 10%), accuracy (recovery range 94.8–108%), repeatability (RSD values 2.53 to 7.19% for white wine and 1.96 to 9. 5% for red wine), and reproducibility (RSD values 2.08 to 12.69% for white wine and 5.21 to 14.77% for red wine). All validation parameters are considered acceptable in characterization of organic acids in wine. The results obtained for the samples studied showed similar content of organic acids to those found for wines from other regions of the world. Principal component analysis (PCA) was applied to verify the applicability of the quality control of the wines and resulted in the correct separation of the samples according to the variety.