La fragancia del color de la uva: el contenido de antocianos altera el microambiente de la uva afectando a su composición de precursores aromáticos

Abstract

The presence or absence of anthocyanins in red/black or white grapes, respectively, conditions the colour of the wines that can be produced. To assess for additional consequences in fruit ripening and composition that this change in grape colour may have, in this study we compared white– and black–berried variants of the ‘Tempranillo’ and ‘Garnacha’ cultivars. The results identified that berry temperature was >3ºC higher in black than in white fruit variants. Transcriptomic and metabolomic analyses detected the activation of light–responsive genes in the white berried variants, including higher expression of secondary metabolism genes that led to a higher accumulation of monoterpenes, norisoprenoids, carotenoids aroma precursors or volatile fatty acid–derived aldehyde. White grapes also accumulated higher levels of phenylpropanoid precursor amino acids and showed lower expression of pathogen defence genes and lower accumulation of GABA, trihydroxylated flavonols, and C6 alcohol and ester volatiles. These findings show that berry skin anthocyanin levels modulate the internal fruit microclimate determining the potential flavour of grapes and wines.