Mono- and sesquiterpenoid fingerprinting: A powerful and streamlined solution for pine nut authentication

Abstract

This study proposes a novel authentication method for pine nut geographical and botanical origin, using mono- and sesquiterpene fingerprints (extracted ion chromatograms from specific ions) analysed via solid-phase microextraction coupled with gas chromatography–mass spectrometry, combined with chemometrics (partial least squares – discriminant analysis). It was tested on 253 samples from China, Russia (major producers of Pinus koraiensis and Pinus sibirica), Spain and Turkey (supplying Pinus pinea), across harvest years. The method achieved 100 % accuracy in external validation when distinguishing Spanish from non-Spanish pine nuts, and 99 % accuracy in differentiating Pinus pinea samples from two distinct Spanish regions. This simple, affordable, and automatable approach proves to be an effective screening tool. It could support official controls in preventing pine nut counterfeiting, as these highly valued nuts have sensory and nutritional characteristics influenced by their species and origin, which, in turn, affect their price.

This work was developed in the context of the project TRACENUTS, PID2020-117701RB-I00 financed by MICIU/AEI/ 10.130 39/501100011033. B. Torres-Cobos thanks the Spanish Ministry of Universities predoctoral fellowships FPU20/01454