analytica chimica acta 614 ( 2 0 0 8 ) 134–142 available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/aca Modelling aroma of three Italian red wines by headspace-mass spectrometry and potential functions Carla Armanino, Maria Chiara Casolino * , Monica Casale, Michele Forina Department of Pharmaceutical and Food Chemistry and Technology, University of Genoa, Via Brigata Salerno 13, I-16147 Genova, Italy article info Article history: Received 8 January 2008 Received in revised form 10 March 2008 Accepted 11 March 2008 Published on line 16 March 2008 Keywords: Headspace-mass spectrometry Wine aroma Experimental design Potential functions Chemometrics abstract The aromas of 41 samples of wine from two Italian regions, Piedmont and Tuscany, were analysed by headspace-mass spectrometry. Samples were from three Italian wines (Bar- bera, Dolcetto and Chianti) produced in the same vintage, from different grape varieties and producing zones. The headspace generating conditions were optimised by full factorial experimental design then chemometric techniques were applied to verify the discriminat- ing power of headspace-mass spectrometry among the three wine aromas. The modelling method based on potential function, applied on the first nine significant components of the 201 measured m/z, revealed best discrimination among the three wine aromas: cross- validated mean prediction rate of 96.7% and mean prediction rate of 83.3% on external test sets were obtained. © 2008 Elsevier B.V. All rights reserved. 1. Introduction Aroma is an important characteristic of wine contributing to its quality. It is a complex mixture of hundreds of volatile chemical compounds, esters, terpenes, ethers, organic acids, aldehydes and ketones, present as main components or at trace level [1]. Variations in concentration of these compounds depend on several factors, firstly the grape variety then pro- duction areas and climate, ageing, process of production and treatments. In recent years several authors proposed analytical meth- ods aimed to discriminate among wines by their aroma, searching for a technique simpler and faster than the pre- viously developed based on distillation or solvent extraction. Headspace solid-phase microextraction (SPME) [2–9], joined to chromatographic separation, was used for the identification ∗ Corresponding author. Tel.: +39 0103532374. E-mail address: casolino@dictfa.unige.it (M.C. Casolino). and quantification of the main components of the bouquet of several wines. Static headspace method, fast and without sample treat- ment, was applied to discriminate several foods by their aroma: olive oil [10,11], vinegar [12,13] and wine [14–18]. Chemometrics has demonstrated to be a powerful tool to discriminate aroma compounds of wines when coupled to separation methods [3,4,19–21] and to different type of sensors [22–27]. When the separation phase is not involved, chemo- metrics becomes the crucial step for resolving the information sent to the analyser [10–13,17]. In this paper, the headspace-mass spectrometry (HS-MS) instrument assembled in our laboratory was tested by an experimental design to find the best conditions for analysing wine headspace: aqueous complex matrix, characterised by huge presence of ethanol. In the optimised conditions the 0003-2670/$ – see front matter © 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.aca.2008.03.025