Relationship Between Chemical Markers and Sensory Score of Traditional Balsamic Vinegars Using a Screening Approach Combined with Rapid Assessment Methods Andrea Versari & Giuseppina Paola Parpinello & Arianna Ricci & Matteo Meglioli Received: 16 January 2013 / Accepted: 25 February 2013 # Springer Science+Business Media New York 2013 Abstract In this study, 200 samples of traditional balsamic vinegar (TBV) of Reggio-Emilia, a typical Italian “aged dress- ing” with Protected Denomination of Origin, were analyzed to model the relationship between sensory scores with some pre- selected compounds/parameters, such as Brix value, water activity (a w ), titratable acidity, color, polymeric compounds, and electronic nose signal. Statistical techniques, such as nonlinear regression and Principal Component Analysis (PCA) were used to model the relationship among vinegars composition. The sensory score of panelists was mainly cor- related with Brix (r =0.85) followed by brown color at 445 nm (r =0.74) and water activity (a w )(r = -0.79), whereas the poly- meric compounds content showed a negative correlation with water activity (r = –0.73). In particular, the water activity of TBVs at different Brix values followed a nonlinear trend with good fitting (r =0.857) with K =3.10 that was consis- tent with the value reported in the literature for fructose and glucose. Electronic nose (enose) data from TBVs and six marker compounds (acetic acid, butyric acid, vanillin, ethyl- phenylacetate, phenylethyl alcohol, and furfural) combined with PCA revealed a pattern related to the ageing of TBVs. Keywords Capillary electrophoresis . Enose . Melanoidins . Norrish model . Sensory . Vinegar . Water activity Introduction Traditional balsamic vinegar (TBV) of Reggio-Emilia is a dark, creamy, and tasty syrup obtained from the alcoholic fermentation and acetic bio-oxidation of cooked grape must aged in small wood barrels for at least 12 years (up to 25 or 40 years). TBVof Reggio-Emilia is classified as “aged dress- ing” (GURI 1987) and has been recently distinguished with the “Protected Designation of Origin” (PDO) by the European Union (Commission Regulation (EC) No. 813/2000). The actual PDO certification of TBV is based on sensory evalua- tion together with two simple physical-chemical parameters: total acidity and density (GURI 2000). However, TBV is a complex mixture of water and numer- ous classes of compounds, including carbohydrates, organic acids (Cocchi et al. 2006), phenolics (Plessi et al. 2006), furans (Masino et al. 2005), melanoidins (Falcone and Giudici 2008; Falcone et al. 2011; Falcone et al. 2012), and volatiles (Chinnici et al. 2009; Xiao et al. 2011). In particular, melanoidins are colored polymers produced during grape must heating (Piva et al. 2008) mainly by Maillard condensa- tion reactions of sugar and amino acids (Montevecchi et al. 2010) or other mechanisms that lead to nitrogen-free melanoidins (Falcone et al. 2011). The composition of TBV is variable and depends on sev- eral factors, mainly the raw material, the acetification system used, and the ageing in wood barrels during which the product undergoes a further slow concentration process by water evaporation through the staves of the barrels. Moreover, every year, new cooked must is added and aliquots of product are transferred from barrel to barrel (Fig. 1). This procedure generates a blend of vinegars of different ages (Giudici and Rinaldi 2007) and composition. In the first barrels, the alco- holic fermentation and a subsequent acetic bio-oxidation A. Versari (*) : G. P. Parpinello : A. Ricci : M. Meglioli Department of Agricultural and Food Sciences, University of Bologna, Piazza Goidanich 60, Cesena, FC 47023, Italy e-mail: andrea.versari@unibo.it Present Address: M. Meglioli Mosti Mondiale, 6865 Route 132, Ville Sainte-Catherine, QC J5C 1B6, Canada Food Anal. Methods DOI 10.1007/s12161-013-9594-8