Aging on-lees

Fornairon-Bonnefond, C. and Salmon, J. M. (2003). Impact of oxygen consumption by yeast lees on the autolysis phenomenon during simulation of wine aging on lees.. Agric. Food Chem. 51, 2584 2590. 

Del Barrio-Galan, R., Perez-Magarifio, S., and Ortega-Heras, M. (2011). Techniques for improving or replacing ageing on lees of oak aged red wines The effects on polysaccharides and the phenolic composition. Food Chem. 127, 528-540. 

Hernandez, T., Estrella, I., CarlavUla, D., Martin-Alvarez, P.J., Moreno-Arribas, M.V. (2006). Phenolic compounds in red wine subjected to industrial malolactic fermentation and ageing on lees. Anal. Chim. Acta, 563, 116-125. 

Fornairon-Bonnefond, C., Camarasa, C., Moutounet, M., Salmon, J.M. (2002). New trends on yeast autolysis and wine ageing on lees A bibliographic review. J. Int. Sci. Vigne Vin, 36, 49-69. 

Traditional practices, such as white wine aging on lees in barrels for several months, confer the wine s tartaric salt stability, which dispenses them from any cold stabilization treatment. It has indeed been observed (Moine-Ledoux and Dubour-dieu 2007) that, in the Bordeaux wine-growing area, the majority of dry white wines aged on lees which are not stable in March after their first winter but become stable in June or July without any supplementary cold treatment (Table 5.1). In contrast, wines within the same crus which are not aged on lees systematically undergo cold treatment to obtain stability regarding tartaric salt crystallization. 

It is well established that, during wine aging on lees, yeasts release mannoproteins that are able to prevent tartrate salt precipitation as was demonstrated first by Lubbers et al. (1993) in model wine solutions. Lubbers et al. (1993) used heat-extracted mannoproteins in alkaline buffers, that is, conditions very different from the spontaneous release of proteins during aging on lees. Nevertheless, Moine-Ledoux and Dubourdieu (1999) reported that heat-extracted mannoproteins added at a dose of 25 g/hL do not show any stabilizing effect as regard to tartrate salt precipitations in red, ros6 and white wines. 

Table 5.1 Evolution of tartaric salt stability estimated by cold testing (six days at —4°C) of different white wines aged on lees throughout two vintages (Reprinted with authorization from Moine-Ledoux and Dubourdieu 2007)...

Other authors have searched for alternative treatments for the use of bentonites, particularly the yeast mannoproteins owing to the fact that a systematic improvement of protein stability can indeed be observed in white wines during aging on lees in barrels (Ledoux et al. 1992). Aged on lees, new wines become decreasingly... 

Fig. 5.7 Electrophoresis diagram of proteins in a Sauvignon wine after alcoholic fermentation left) and after 10 months aging on lees (right) (redrawn with permission from Moine-Ledoux and Dubourdieu 2007)...

Table 6A.1 Average biogenic amine concentrations (mg/L) for different levels of vintage, pectolytic enzymes, aging on lees, maceration time and bacteria inoculation (from Martin-Alvarez et al. 2006, with permission)... 

Doco, T., Vuchot, R, Cheynier, V., Moutounet, M. (2003). Structural modification of wine ara-binogalactans during aging on lees. Am. J. Enol. Vitic., 54, 150-157. 

Yeast cell walls are present in white wines which were aged on lees. Therefore we can suggest that yeast walls fi om lees influence on the equilibrium of the bouquet of the wine. 

Smit, A. Y, du Toil, M. (2013). Evaluating the influence of malolactic fermentation inoculation practices and ageing on lees on biogenic amine production in wine. Food and Bioprocess Technology, 6, 198-206. http //dx.doi.org/10.1007/sll947-011-0702-8. 

Fig. 13.15. E roportions of eUagic tannins of a barreled wine aged on lees or without lees (Chatonnet et al., 1992)...

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