Determination of the geographical origin of valencia orange juice using carotenoid liquid chromatographic profiles

We present a simultaneous liquid chromatographic method for quantitation of the major carotenoid pigment in pure valencia orange juice from two countr y origins. This technique involves the use of a C-30 non-endcapped reversed -phase column and a ternary gradient, methanol-methyl tert.-butyl ether-wat er. Identification of carotenoids is achieved using a photodiode array dete ction at 350, 430 and 486 nm. The spectra of saponified carotenoid pigments from 23 orange juices samples were compared and discussed in the context o f results that were published previously. The behaviour of the C-30 column with time, on the resolution of two carotenoids, zeaxanthin and isolutein i s discussed. This technique has been applied to the determination of the ge ographical origin of carotenoid compounds using eighteen samples of valenci a pure orange juice from two countries (Belize and Spain), collected over t wo consecutive years. Quantitative determination seems to be a convenient m ethod for determination of the origin of orange juice. The total carotenoid s considered were higher in valencia juice from Spain (17.0+/-5.0 mg l(-1)) than in valencia juice from Belize (4.8+/-1.0 mg l(-1)). Some carotenoids play a large role in origin differentiation, such as phytofluene, which is lower from Belize than from Spain (0.5 vs. 1.8%), or xi-carotene, which is higher in valencia from Spain (4.9%) than in valencia from Belize (1.8%). ( C) 1999 Elsevier Science B.V. All rights reserved.