European Food Research and Technology

, Volume 245, Issue 11, pp 2515–2528 | Cite as

Chemometric tools for determining site-specific elemental and strontium isotopic fingerprints in raw and salted sturgeon caviar

  • Anastassiya Tchaikovsky
  • Andreas ZitekEmail author
  • Johanna Irrgeher
  • Christine Opper
  • Rudolf Scheiber
  • Karl Moder
  • Leonardo Congiu
  • Thomas Prohaska
Original Paper


This study presents a chemometric protocol for the determination of site-specific elemental and strontium isotopic fingerprints in sturgeon caviar. The elemental and strontium isotopic composition of water, fish feed, salt, raw (i.e., unsalted) and salted sturgeon caviar samples from six fish farms in Europe and Iran was determined by (multi-collector) inductively coupled plasma mass spectrometry ((MC) ICP–MS). Multiple linear regression revealed six site-specific markers absorbed from water into sturgeon caviar (n(87Sr)/n(86Sr) isotope ratio and content of Na, Mn, Cu, Mo, Fe/Ca). Salting changed the chemical composition of four (n(87Sr)/n(86Sr), Na, Mn, Fe/Ca) of the six site-specific markers significantly. Washing of salted caviar could not fully remove the influence of salt on the affected site-specific markers. Therefore, a novel mathematical procedure based on mass balance calculations was developed for determining the n(87Sr)/n(86Sr) isotope ratio absorbed from water into sturgeon caviar. The resulting variable is an estimate for the environmental strontium isotopic signal and independent of the production process. Hierarchical cluster analysis showed that the combination of the mathematically determined n(87Sr)/n(86Sr) isotope ratio of water in sturgeon caviar and two site-specific markers, which were not affected by salting (Cu, Mo), allowed differentiating salted caviar samples from six fish farms into five distinct clusters. The proposed combination of statistical and mathematical tools provides the basis for origin determination of salted sturgeon caviar using site-specific elemental and strontium isotopic fingerprints, even in cases where the initial environmental signature was altered by the production process.


Strontium isotopes Food traceability Isotope pattern deconvolution Mixing models Fish products 



The authors acknowledge the Federal Ministry of Science, Research and Economy for funding the research within the Sparkling Science program (Project “CSI: Trace your Food”, SPA 05_052). We acknowledge the support of the project by the COMET-K1 competence centre for Feed and Food Quality, Safety & Innovation (FFoQSI). The COMET-K1 competence centre FFoQSI is funded by the Austrian ministries of Transport, Innovation and Technology (BMVIT), Digital and Economic Affairs (BMDW) and the Austrian provinces Niederoesterreich, Upper Austria and Vienna within the scope of COMET—Competence Centers for Excellent Technologies. The programme COMET is handled by the Austrian Research Promotion Agency (FFG). We gratefully thank the project cooperation partners Wolfgang Grüll (Grüll GmbH, Gröding, Austria), Mario Pazzaglia (Agroittica Lombarda SpA, Italy) and Shima Bakhshalizadeh (University of Gulian, Iran) for providing the samples, Jennifer Sarne and Melanie Diesner for their support with sample preparation as well as David Markvica for proofreading.

Compliance with ethical standards

Conflict of interest

There are no conflicts of interest to declare.

Compliance with ethic requirements

Caviar collection was conducted in compliance with ethical standards using standard aquaculture practices in the respective countries.

Supplementary material

217_2019_3363_MOESM1_ESM.pdf (751 kb)
Supplementary material 1 (PDF 751 kb)
217_2019_3363_MOESM2_ESM.xlsx (35 kb)
Supplementary material 2 (XLSX 35 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Anastassiya Tchaikovsky
    • 1
    • 6
  • Andreas Zitek
    • 1
    • 2
    Email author
  • Johanna Irrgeher
    • 3
    • 7
  • Christine Opper
    • 2
    • 7
  • Rudolf Scheiber
    • 2
  • Karl Moder
    • 4
  • Leonardo Congiu
    • 5
  • Thomas Prohaska
    • 2
    • 7
  1. 1.FFoQSI GmbH-Austrian Competence Centre for Feed and Food Quality, Safety and InnovationTullnAustria
  2. 2.Department of Chemistry-VIRIS LaboratoryUniversity of Natural Resources and Life Sciences, ViennaTullnAustria
  3. 3.Department of Marine Bioanalytical ChemistryHelmholtz-Centre for Materials and Coastal ResearchGeesthachtGermany
  4. 4.Institute of Applied Statistics and ComputingUniversity of Natural Resources and Life Sciences, ViennaViennaAustria
  5. 5.Department of BiologyUniversity of PadovaPaduaItaly
  6. 6.Department of Analytical ChemistryUniversity of ViennaViennaAustria
  7. 7.Chair of General and Analytical ChemistryMontanuniversität LeobenLeobenAustria

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