The aroma of carbonic maceration wines: An in-depth chemical composition analysis RICARDO LÓPEZ1, OLIVIER GEFFROY2, BELÉN CONCEJERO1, ERIC SERRANO2, JUAN CACHO1, VICENTE FERREIRA1 1Laboratorio de análisis del aroma y enología. Instituto de Investigación en Ingeniería de Aragón (I3A). Departamento de Química Analítica. Universidad de Zaragoza. C/Pedro Cerbuna, 12. 50009 Zaragoza (SPAIN) 2Institut Français de la Vigne et du Vin Pôle Sud-Ouest, V’innopôle, BP22, 81 310 Lisle Sur Tarn (France)

1.-Introduction 2.-Experimental design Carbonic maceration (CM) is an anaerobic maceration technique used in different countries, and specially in the French region of Beaujolais, to produce In order to study CM, vinifications following this procedure were conducted for 3 years on Grenache, young wines with a unique fruity aroma. CM has been studied before but the Carignan and Fer Servadou monovarietal wines (n=14). Fourteen standard vinifications were also carried exact chemical nature of the volatiles causing this characteristic aroma is still not out with the same grapes as control wines (CTR). completely clear. Researchers have linked the fruity aroma of these wines to Conventional enological parameters and 78 volatile compounds were analysed (3-5) in the bottled higher contents of ethyl cinnamate, benzaldehyde, ethyl esters and volatile wines. Sensory evaluation was conducted by a specialized trained panel consisting of 8 tasters, and also phenols, and lower contents of C6 compounds (1-2). by including the wine samples in a sorting task experiment with 14 panelists. In the present study, we have carried out an exhaustive analysis of the volatile A 2-way ANOVA treatment (carbonic maceration x variety) was performed on the collected data. chemical composition and sensory profile of three monovarietal wines during Aroma reconstitution models were prepared by mixing compounds in a solution of propylenglicol and three vintages to fully understand the changes induced in their chemical profile ethanol. and aroma by CM treatment. With this data, we have prepared a reconstitution model of the CM wines. 3.-Sensory evaluation 4.-Volatile composition 4,0 Isoamyl acetate (mg/L) 3,5 3,0 Different types of vinification of the same grapes were Control wine Carbonic Maceration wine compared in a sorting task experiment. The data 2,5 treatment was a multidimensional scaling (MDS) and Phenylethyl acetate 2,0 further Hierarchical Cluster Analysis (HCA) in order to Butyl acetate 1,5 establish clusters of wines sharing a common aroma. 1,0 Isobutyl acetate The examination of the HCA plots derived from the 0,5 Isoamyl acetate MDS showed that CM wines emerged as a single cluster, Odor threshold - which clearly indicated that these wines were globally Ethyl isobutyrate Carignan Grenache Fer Servadou 100 perceived as very different from the rest of samples Ethyl decanoate Ethyl cinnamate (µg/L) according to their general aroma. 90 Ethyl butyrate 80 Ethyl propanoate 70

Ethyl acetate 60 The individual cluster corresponding to CM 50 wines was described by the aromatic terms Methionol 40 “strawberry”, “lactic” and “floral”. β-phenylethanol 30 Figure: Hierarchical cluster analysis for Grenache wines 2010 Benzyl alcohol 20

(Z)-3-hexenol Odor 10 threshold 0 1-Hexanol Carignan Grenache Fer Servadou 5.-Aroma reconstitution Isobutanol 16 Diacetyl (mg/L) Benzaldehyde 14 12 Diacetyl Aroma reconstitution experiments on the basis of quantitative differences in OAV were 10 Isovalerianic acid undertaken to mimic the aroma of carbonic maceration wines. 8 Isobutyric acid The five compounds with highest ∆OAVs between Carbonic Maceration wine and Control 6 wine were enough to produce a reconstituted wine described by tasters as typical carbonic Decanoic acid 4 Odor Octanoic acid threshold2 maceration style.

Acec acid 0 Carignan Grenache Fer Servadou Ethyl cinnamate Isoamyl acetate 120 Ethyl dihydrocinnamate Ethyl acetate (mg/L) Ethyl cinnamate 100 Reconstituted Geraniol Reconstituted Diacetyl 80 Carbonic β-damascenone neutral Ethyl acetate 60 Maceration β-citronellol red wine β-damascenone α-terpineol 40 wine

Linalool 20 Odor threshold 4-vinylphenol 0 Carignan Grenache Fer Servadou Eugenol 16 β-damascenone (µg/L) 2-furfurylthiol 14 Acetovanillone 12

Ethyl vanillate 10

Methyl vanillate 8 6 Vanillin 4 -4,00 -3,00 -2,00 -1,00 0,00 1,00 2,00 3,00 4,00 2 YOU CAN SMELL THEM HERE Figure: Standard average content differences (adimensional) Odor threshold0 between Carbonic maceration and control wines in selected Carignan Grenache Fer Servadou volatiles DURING THIS POSTER SESSION!

6.-Conclusions 7.-References

1.- The carbonic maceration wines presented significantly higher contents of ethyl esters of cinnamate and dihydrocinnamate, acetates, fatty 1.-Versini, G., and Tomasi, T. L'enotecnico, 19, 595 (1983). β acids and their ethyl esters, monoterpenols, -damascenone, vanillin derivatives and some volatile phenols. 2.-Ducruet,V., C.Flanzy, M.Bourzeix, and Y .Chambroy. Sci. Aliments. 3, 413 (1983). 2.-Comparing with control wines, carbonic maceration wines had lower contents of C6 and fusel alcohols, and also of branched acids and 3. Lopez, R., Aznar, M., Cacho, J., & Ferreira, V., J. Chrom.A, 966 (1-2), 167 (2002). their ethyl esters. 4. Ortega, C., López, R., Cacho, J., & Ferreira, V., J. Chrom. A, 923(1-2), 205 (2001). 3.-A strong varietal influence was observed. Fer servadou wines showed less changes than Grenache or Carignan wines. 5. Mateo-Vivaracho, L., Cacho, J., & Ferreira, V., J.Chrom. A, 1185(1), 9 (2008). 4.-Five key components were enough to give a neutral model wine the characteristic aroma of carbonic maceration wines Acknowledgements This work has been funded by the EU-FEDER “Programa operativo de cooperación territorial España-Francia-Andorra”, project VINAROMAS EFA84/08