Winemaking maceration time

Gambuti, A., Strollo, D., Ugliano, M., Lecce, L., Moio, L. (2004). tra s-Resveratrol, quercetin, (-t)-catechin, and (-)-epicatechin content in south italian monovaiietal wines Relationship with maceration time and marc pressing during winemaking. J. Agric. Food Chem., 52, 5747-5751. 

By taking into account the previously mentioned notions, general red winemaking principals can be improved for the better control of maceration time and intensity. 

The tannin/anthocyanin ratio permits the two winemaking methods (direct pressing and drawing off) to be differentiated. This ratio diminishes as the maceration time increases and it is higher when the grapes are directly pressed. 

The first steps of winemaking with maceration consist of moderately crushing and destemming the grapes. The grapes are then transferred to the tank and sulfited at 5-10 g/hl. The fermentation temperature is set at approximately 30°C to favor maceration. Maceration times vary from 2 to 8 days, if the fortification occurs after must separation. In this case, the fermentation speed should be reduced beforehand. Wines are macerated for 8 to 15 days when continuing the maceration after fortification. 

Total phenols extracted into red wines by skins and seeds usually increase with an increase in contact time, temperature, ethanol, SO2, and maceration. These are the factors at the winemaker s disposal that have a large effect upon the style of wine he wishes to produce. 

Winemaker s opinions vary as to the timing of starter inoculation. In the survey of Fugelsang and Zoecklein (1993), 41% of red wine producers added starters during the course of alcoholic fermentation, 17% at the end, and 17% after pressing at the end of extended maceration. The situation was quite different for white wine producers 25% inoculate at the same time as yeasts, 15% early in alcoholic fermentation, 48% at some stage of later fermentation, 9% upon completion (but before first racking) and 3% after first racking. 

In red winemaking, these preparations are used in particular for press wines and heat-treated grapes and must. In the latter case, the must is very rich in pectic compounds and devoid of endogenous grape enzymes. These are destroyed by heat (Martiniere and Ribereau-Gayon, 1973). Pectolytic enzymes can also be used at the time of running off after a traditional maceration. 

During the second fermentation phase, the complete transformation of sugar into alcohol is generally very quick. It is carried out at 18-20°C to preserve aroma components. Afterwards, the favorable conditions permit the easy initiation of malolactic fermentation. Despite the existence of two distinct phases, carbonic maceration requires less time than traditional winemaking. This method is therefore well adapted for wines that are quickly put on the market. 

Contact time, temperature and sulfiting are factors that influence phenolic compound dissolution and color in rose wines (Castino, 1988). Sulfur dioxide is known to have a certain dissolvent power (Section 8.7.5). It is not manifested during traditional red winemaking, due to the preponderant effects of other factors (duration, temperature and pumping-over). Yet when maceration is limited, the effect of sulfiting is obvious. Table 14.3 shows the impact of the winemaking techniqne on the color intensity and phenolic componnd concentrations of rose wines. Sulfiting promotes anthocyanin dissolution and color enhancement. It is not easy to control the conditions that will produce the required color and phenolic structure, as they depend on the specific characteristics of the wine. 

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