Use of capillary electrophoresis for monitoring citrus juice composition

New trends in adulteration monitoring, favor the development of methods analyzing simultaneously as many compounds as possible. Capillary electrophoresis has been applied to the examination of a broad spectrum of citrus juice molecules that absorb in the UV and in the visible light. Depending on the conditions up to thirty compounds could be separated. The identified molecules included phenolic amines, amino acids, flavonoids, polyphenols and vitamin C. Samples can be analyzed without specific preparation and the best separations were obtained with diluted solutions due to a stacking effect. This method has been applied to the comparison of pure orange juice and pulpwash, a major adulterant of orange juice. Several significant quantitative differences were seen and it is hoped that this procedure will provide a more precise way of estimating pulpwash in orange juice.