Short communication: A survey on the rotundone content of eighteen grape varieties sourced from a germplasm collection during a cool season
Résumé
The aim of this work was to quantify rotundone by SPE-SPME-GC-MS in grape samples from eighteen varieties collected from a germplasm collection to investigate their aptitude to produce rotundone. The analytical method showed a good linearity (R2 = 0.9995), repeatability (< 9 %), and satisfactory limits of detection (∼7 ng/kg) and quantification (∼20 ng/kg). Surprisingly during this cool season, rotundone was not detected in Vitis vinifera L. cv. Gamay and Grüner Veltliner - some known rotundone-producing varieties - and was only found in Fer, Duras, Syrah, Tardif, and for the first time at such level of concentration in Grenache. Our findings that suggest the existence of three classes of rotundone producers (no/low, moderate and high) with the level of production being modulated within a class by environmental conditions would deserve to be confirmed during another season.