OBJECTIVES

The use of natural isotopic abundances has an enormous potential. In fact, organic and non-organic growth conditions can directly lead to differences in specific isotopic abundance (source effect), or modify the physiology of the plant, impacting isotope fractionations (physiological effect).

Stable isotopes have been used for over 50 years to authentify geographical origin, botanical origin, etc., but are rarely used for organic certification. Several studies have shown the potential of raw isotopic signatures of commercialised plant products, but with limited efficacy.

That said, specific isotopic analyses targeted to individual compounds, or within molecules themselves (intramolecular signatures), have some potential to become a powerful tool. The aim of this project is to explore such refined analyses, using wine as a raw material, in order to answer the following questions:

1. Can natural isotopic signatures be used to differentiate organic and non-organic products, in particular, using several isotopes simultaneously?
2. At what level analyses should be carried out: raw, compound-specific or intramolecular?
3. 3.    How does the performance of the isotopic approach compare with that of biometric approaches such as NMR¹, LC-MS² and NIRS³?

¹NMR: nuclear magnetic resonance
²LC-MS: liquid chromatography mass spectrometry
³NIRS: near-infrared spectroscopy

RESOURCES

This project mobilizes skills in isotopic biochemistry, analytical chemistry, plant physiology and metabolism. It also requires statistical analysis (machine learning) and comparison with biometric methods.

Participants

INRAE units

• IRHS, Angers
• BFP, Bordeaux
• Œnologie, Bordeaux

Partners

• Université de Nantes/CNRS