Characterization of paprika (Capsicum annuum) extract in orange juices by liquid chromatography of carotenoid profiles.

The carotenoid pigment profiles of authentic pure orange juices from Spain and Florida and an industrial paprika (Capsicum annuum) extract used for food coloring were obtained using reversed-phase liquid chromatography with a C18 packed column and an acetone/methanol/water eluent system. The procedure involving the carotenoid extraction is described. Both retention times and spectral properties using photodiode array detection for characterization of the major carotenoids at 430 and 519 nm are given. The influence of external addition of tangerine juice and/or paprika extract on orange juice color is described using the U.S. Department of Agriculture scale and adulterated orange juice. The procedure for quantitation of externally added paprika extract to orange juice is investigated, and the limit of quantitation, coefficient of variation, and recoveries are determined.

Differentiation of several geographical origins in single-strength Valencia orange juices using quantitative comparison of carotenoid profiles.

Pure Valencia orange (Citrus sinensis) juices (64 samples) from Spain, Israel, Belize, Cuba, and Florida, harvested during two seasons (1996-1997 and 1997-1998), were analyzed for their carotenoid profiles. The detection of saponified carotenoid pigments has been achieved and quantitated using a photodiode array detection monitored at 350, 430, and 486 nm. Carotenoid pigments commonly found in the orange variety Valencia have been separated on a polymeric C-30 column using a ternary gradient as eluent. Pure Valencia juices from oranges grown in Mediterranean regions (Israel and Spain) have a high carotenoid content, expressed in beta-carotene (5-18 and 14-35 mg L(-)(1), respectively), compared to those grown in tropical and subtropical regions (Cuba, Belize, and Florida) (4-10, 2-8, and 5-10 mg L(-)(1), respectively). Quantitative results allowed the differentiation of Valencia variety geographical origins, in particular, the Mediterranean area from tropical and subtropical areas, using multidimensional analyses of carotenoid contents.

Differentiation of several geographical origins in single strength Valencia orange juices using quantitative comparison of carotenoid profiles

Pure Valencia orange (Citrus sinensis) juices (64 samples) from Spain, Israel, Belize, Cuba, and Florida, harvested during two seasons (1996-1997 and 1997-1998), were analyzed for their carotenoid profiles. The detection of saponified carotenoid pigments has been achieved and quantified using a photodiode array detection monitored at 350, 430, and 486 nm. Carotenoid pigments commonly found in the orange variety Valencia have been separated on a polymeric C-30 column using a ternary gradient as eluent. Pure Valencia juices from oranges grown in the Mediterranean regions (Israel and Spain) have a high carotenoid content, expressed in beta-carotene (5-18 and 14-35 mg L(-)(1), respectively), compared to those grown in tropical and subtropical regions (Cuba, Belize, and Florida) (4-10, 2-8, and 5-10 mg L(-)(1), respectively). Quantitative results allowed the differentiation of Valencia variety geographical origins, in particular, the Mediterranean area from tropical and subtropical areas, using multidimensinal analyses of carotenoid contents. (AU)