Multi stable isotope ratio analysis for the traceability of northern Italian apples

Valentina Brombin; Enrico Mistri; Gianluca Bianchini

doi:10.1016/j.fochx.2022.100514

Multi stable isotope ratio analysis for the traceability of northern Italian apples

Food Chem X. 2022 Nov 17:16:100514. doi: 10.1016/j.fochx.2022.100514. eCollection 2022 Dec 30.

Authors

Valentina Brombin¹, Enrico Mistri¹, Gianluca Bianchini¹

Affiliation

¹ Department of Physics and Earth Sciences, University of Ferrara, Via Giuseppe Saragat 1, 44122 Ferrara, Italy.

Abstract

Isotope ratio mass spectrometry is a well-known technique used to trace the origin of agri-food products from different countries. Here this method was tested to trace the exact orchard of provenance of Italian apples harvested at sites close to each other. We measured the δ¹³C, δ¹⁵N, and δ³⁴S values of apple subfractions (peel, petiole, pulp, seed) from two orchards in Ferrara and one orchard in Trento. Sulfur represents the best marker for tracing the regions of provenance of samples because it is linked to the presence of sulfate (Ferrara1: +9.0 ‰; Ferrara 2: +7.3 ‰) and sulfide (Trento: -1.3 ‰) minerals in soils. However, the δ¹³C of apple subfractions combined with the δ³⁴S of seed in a linear discrimination analysis better discriminated the three orchards. The isotopic fingerprint of apples is thus significantly affected by the relative terroir, and it can be used as "isotopic identity card" to certify "protected designations of origin".

Keywords: Apples; Isotope ratio mass spectrometry; Multi-isotopic analysis; Protected designations of origin; Traceability.