Stable carbon isotope ratio analysis of Australian orange juices

Data are presented for stable carbon isotope ratio analysis on Australian orange juices (273 fresh and 80 concentrated samples) representing production over a five year period, with a view to establishing a database of authentic values to be used for adulteration testing. Peel extracts of Australian origin (40 samples), Brazilian pulpwashes (38 samples) and Brazilian concentrates (42 samples) were also tested. The internal correlation between carbon isotopes in sugars and acids has been determined for selected samples of fresh juice. Differences between these components ranged from 0.7 to 1.5‰. The data for fresh juices show regional differences in isotopic abundances, which are related to rootstock.