ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The use of stable isotopes ratios for authentication of fruit juices

Dana Alina Magdas, Nicoleta Simona Vedeanu, and Romulus Puscas

National Institute for Research and Development of Isotopic and Molecular Technologies, Donath 71-103, 400293 Cluj-Napoca, Romania

E-mail: nicoletavedeanu@yahoo.com

Abstract: The determination of the content of stable isotopes, ¹⁸O and ²H, respectively, in juice water facilitates the distinction between authentic juices and juices made from concentrates by redilution with tap water. At the same time, the detection of C₄ cane or corn-derived sugar syrups in fruit juices which are produced from C₃ fruit types is thus facilitated by the characteristic differences in ¹³C/¹²C, expressed as δ ¹³C (‰) values due to photosynthetic CO₂ assimilation via the C₃₋, C₄₋, and crassulacean acid metabolism pathways. In this study, the quantitative determination of water added to an authentic juice, on the basis of δ ¹⁸O, and δ ²H values, respectively, was successfully performed. Also, the δ ¹⁸O, and δ ²H of juice water and δ ¹³C of the whole juice in 18 samples were also determined. The results obtained provided us with the possibility of distinguishing between authentic fruit juices and those obtained by redilution of concentrated fruit juices and the detection of C⁴ type added sugar.

Keywords: fruit juices – isotope ratio mass spectrometry – stable isotope

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-011-0105-3

Chemical Papers 66 (2) 152–155 (2012)