Effect of brandies？ agitation on the kinetics of extraction/oxidation and diffusion of wood extractable compounds in experimental model

this study provides, for the first time, specific information about the effect of brandy？s agitation on the kinetic of extraction/oxidation and diffusion of wood low molecular weight compounds during the first two months of ageing, in barrels of limousin oak wood and chestnut wood submitted to light toasting (ql) and strong toasting (qf). a concentration gradient of compounds was observed in brandy dependent of their chemical nature, the botanical species (higher in the brandies that contact with the chestnut wood) and the wood toasting level (higher in the strong toasting). these aspects justify therefore the brandy？s agitation in the first months of ageing, mainly in barrels of chestnut wood and strong toasting. independently of the wood and the toasting level, the monthly agitation showed to be the more efficient than the static system and the agitation after each sampling, leading to brandies with higher dry extract weight, higher total polyphenol index and higher content of low molecular weight compounds, favouring the balance between extraction and diffusion phenomena.