Modelling phenolic and volatile composition to characterize the effects of pre-fermentative cold soaking in Tempranillo wines

- The effect of two cold soak techniques was investigated against control wines.
- Tempranillo wines were analyzed after twelve months of bottle storage.
- Dry ice addition caused an important effect on wine anthocyanins and volatiles.
- Differences between cold soak techniques were also observed.
- The length of cold soak vs dry ice addition needs to be considered.

The impact of pre-fermentative cold soak, alone or in combination with dry ice addition, on colour, phenolic and volatile composition of Tempranillo wines at 12 months after bottling was studied. A control wine without cold soak was also evaluated. A sample set consisting of 66 wines was investigated. The results from ANOVA and PCA analysis showed significant treatment-related differences for a number of chemical measurements, as well as overlapping effects. Orthogonal projections to latent structures discriminant analysis (OPLS-DA) of the data showed that the dry ice addition treatment had a major effect on the anthocyanin fraction and on the levels of ethyl decanoate, 2-phenylethyl acetate and decanoic acid. In comparison, the cold soak treatment only had a slight effect on the bisulphite bleaching anthocyanins and volatile composition.