δ(15) N from soil to wine in bulk samples and proline

Area of Science:

• Agricultural Chemistry
• Food Science
• Isotope Geochemistry

Background:

• Geographical origin is a key factor in wine quality and value.
• Traditional traceability methods can be complex and costly.
• Nitrogen isotope ratios (δ(15)N) offer a potential new marker for origin tracing.

Purpose of the Study:

• To assess the feasibility of using δ(15)N as an isotopic marker for wine's geographical origin.
• To investigate the entire soil-grape-wine production chain.
• To evaluate the impact of various winemaking processes on δ(15)N values.

Main Methods:

• Analysis of δ(15)N in soil, leaves, grapes, and wine (bulk and proline).
• Studying the effects of fermentation, yeast type, vinification (red/white), nitrogen adjuvants, and ultrasound lysis.
• First-time measurement of δ(15)N in grape must and wine proline.

Main Results:

• δ(15)N values in leaves, grapes, and wine, especially proline, reflect soil δ(15)N variability.
• Fermentation and ultrasound treatments did not alter grape must δ(15)N.
• Adjuvant addition affected bulk wine δ(15)N, but not wine proline δ(15)N.

Conclusions:

• Wine proline δ(15)N is a robust marker for tracing wine's geographical origin.
• Nitrogen isotope analysis, particularly of proline, offers a reliable method for wine authentication.
• This isotopic marker can help ensure wine authenticity and protect regional designations.