Aceto Balsamico Tradizionale di Modena” PDO authenticity: detection of caramel-containing vinegar by HS-GC-IMS

Abstract

Balsamic vinegars of Modena (Italy), namely Aceto Balsamico di Modena PGI (AB PGI) and Aceto Balsamico Tradizionale di Modena PDO (ABT PDO) are among the most important geographical indication products for Italy. ABT PDO, despite its very limited production, is recognized as one of the most representative Italian artisan gastronomic products, and it is known and commercialized all around the world. The economic value of ABT PDO (“affinato” and “extra-vecchio” types, depending on the aging), prepared following a traditional way and aged for many years in a set of barrels (transferring a certain amount of vinegar from one cask to another in a decreasing “topping up” procedure) is great, when compared to AB industrially prepared with caramel. AB PGI is certainly the most widespread industrial-type vinegar in the world, deriving from low-temperature condensed grape must (or cooked must) mixed with wine vinegar, obtaining balsamic vinegars with a caramel-like taste. Depending on its economic value, ABT PDO is often object of fraud, requiring to fight counterfeit products and imitations.
Head Space-GC-Ion Mobility Spectrometry (HS-GC-IMS) is a rapid chromatographic technique useful to obtain 2D separation of volatile compounds from foods, allowing to obtain a specific fingerprint of the aroma with no pre-treatment of the samples. During the last ten years, many applications were developed in food quality and authenticity areas using HS-GC-IMS.
Aim of the present study was to develop a quick authentication model for the recognition of the counterfeit ABT PDO products; different mixture (5, 10, 20%) prepared adding AB PGI in ABT PDO were analyzed, confirming the capacity to identify the presence of concentrated/cooked must-like products in ABT PDO in percentage less than 5% using this rapid method. Some key volatile compounds from AB PGI were easily identified using Kovats index.