Validation of HPLC and CE methods for determination of organic acids in sour cassava starch wastewater

Fast and efficient analytical methods to determine the concentrations of lactic, acetic, propionic and butyric acids in sour cassava starch wastewater using reversed-phase high performance liquid chromatography (HPLC) and capillary electrophoresis (CE), were developed and validated. Good linearity (R2 > 0.999) and significance with F > 25,000 for all acids was showed. The matrix effect was not detected. The coefficient of variation values indicated good repeatability. The limits of detection (LOD) ranged from 1.0 to 3.7 and 2.0 to 3.0, and the limits of quantification (LOQ) from 3.1 to 12.2, and 8.0 to 12.5 mg/L for HPLC and CE, respectively. The quantification of the samples did not reveal significant differences between the methods for all compounds analyzed. However, the benefits of CE in relation to HPLC, such as lower costs and less waste generation, along with shorter analysis times, need to be taken into consideration.