Comparison of analytical methods for determining the orange content of processed juices

Different methods (chemical analysis, comparison of UV spectra, SDS-PAGE and ELISA immunoassay) for determining the orange content of processed juices were studied. Characteristic differences were observed between fruit parts (albedo, flavedo, juice and pulp) and also between varieties in chemical composition (polyphenols, betaine, stigmasterin) and UV spectra. Thus it seems that these parameters may be used for detection of non-citrus additives and also the citrus by-products. SDS-PAGE analysis of water soluble proteins and the ELISA assay using antisera raised in rabbits give only tentative results due to the low specificity of antigens and presence of other probably non-protein immunoactive components.

Comparison of analytical methods for determining the orange content of processed juices Academic Article