Effects of the addition of oak chips (French and American) and aqueous solution tannins extracted from oak wood on the composition of wines
Wednesday 17 May - National Hall
Module managed in collaboration with I-Oak
The speakers will be:
Riccardo Savastano,
Tecnico R&D presso HTS
OnofrioCorona,
Docente di Enologia presso Università di Palermo
Functional compounds of oenological wood
Riccardo Savastano, HTS
The relationship between wine and wood has deep roots that dig into the history of oenology.
The wooden barrel was born from man’s ingenuity and need to preserve and transport this product in the best possible conditions, but today, the stabilizing and improving role of wood in wines is recognized all over the world. This was also possible thanks to the evolution of technology and analytical techniques through which numerous researchers have approached this subject and which have led to understand the nature of the wood itself and to isolate specific molecules.
Ellagitannins, polysaccharides and aromas are the functional compounds on which both the properties and applications of oenological wood depend and in modern oenology, oak chips and tannins in solution are technological tools useful for achieving multiple objectives, including: antioxidant protection, color stability, aromatic cleanliness and improvement of mouthfeel sensations.
Effects of the addition of oak chips (French and American) and aqueous solution tannins extracted from oak wood on the composition of wines
Onofrio Corona, University of Palermo
In this work, the effects of the use of oak chips, French and American oak, and tannins in aqueous solution, extracted from oak wood, on both white and red grape musts were studied. To evaluate the influence of chips and liquid tannins on the kinetics of alcoholic fermentation and on the composition and sensory characteristics of white and red wines, white grape musts obtained from Grillo grapes (western Sicily) were fermented in the presence of French oak chips (not toasted, I-OAK Expression), and in the presence of tannins in aqueous solution (Pratiko® L-Harvest and L-Fruit), at different concentrations, while red musts of Sangiovese Rubicone grapes (Emilia Romagna), were fermented in the presence of French oak chips (untoasted, I-OAK Expression) and French and American oak (medium toast+, I-OAK Trend).
The wines obtained showed significant differences in terms of volatile and non-volatile compounds extracted from chips, both depending on the origin and on the level of toasting. The alcoholic fermentation of the musts was in part favored by the presence of chips and liquid tannins and the wines obtained, compared to the control wines, showed significant differences in fixed (colloids, polyphenols and ellagitannins) and in volatile compounds ( ethyl esters of medium-chain fatty acids and acetates of higher alcohols, phenolic aldehydes, volatile phenols, furan compounds, pyrans).
The chips and tannins added to the musts before alcoholic fermentation have also led to an additional supply of polyphenols capable of inducing more complex sensory profiles in the wines, with a more persistent mouthfeel. The sensory analysis, in fact, highlighted a greater complexity, volume, finesse and aromatic persistence in the wines obtained from musts added with chips, moreover, they were preferred to the test wines both in termsof olfactory and taste profile.
