In this work, a reliable and sensitive CZE method using direct
UV detection for the determination of organic acids in several fruit
juices was described. For this purpose, an optimization study with
simulated real juice samples (containing large variability of organic
acid contents) using different experimental CZE conditions (including
poly(vinyl alcohol) (PVA)-coated capillaries with normal and
with extended-path light was first carried out. The organic acid
content present in different fruit juices was obtained. Next, a linear
discriminant analysis (LDA) model was constructed to classify
juices according to the type of fruit employed and to distinguish
between pure juices and juice blends. Moreover, data treatment
by multiple linear regression (MLR) was used to quantify blends
of high-value juices (pineapple and orange) with grape juice.