Winemaking, rose

Table Grapes (used in winemaking) Rose of Peru, Black Hamburg, Comichon, Tokay, and Emperor gave yields of 4-6 tons per acre in the valley (in the Central Valley), 3-4 tons per acre on the hills (presumably in the Sierra Nevada foothills).

By careful processing, the winemaker brings the wine to a finished state. The white and rose wines will have maintained their bouquet and aroma and flavors. The red table wines will have been softened by careful fining with such agents as gelatin and PVPP, will be fruity, and will have distinctive varietal aromas and flavors with minimal astringency. 

Bellon, J., Rose, L., Currie, B., Ottawa, J., Bell, S., Mclean, H., Rayment, C., Treacher, C., Henschke, P (2008) Summary from the winemaking with non-conventional yeasts workshops, 13th AWITC. Australian New Zealand Grapegrower Winemaker, 528, 72-77. 

In dry white and rose winemaking, excessive must clarification can also lead to the excessive production of volatile acidity by yeast. This phenomenon can be particularly pronounced with certain yeast strains. Therefore, must turbidity should be adjusted to the lowest possible level which permits a complete and rapid fermentation (Chapter 13). Solids sedimentation (must lees) furnishes long-chain unsaturated fatty acids (C18 l, C18 2). Yeast lipidic alimentation greatly... 

However, the dissolvent effect of SO2 is manifest in rose winemaking, since the phenolic compound concentration is low in this case. In fact, SO2 can be detrimental to white winemaking. This dissolvent effect may also affect red grapes if they are insufficiently ripe, and pigment extractability is poor. In that case, snlfiting facilitates anthocyanin extraction in the early stages, especially during cool-temperature maceration (Section 12.5.2). 

Immediately after extraction, the juice should be protected from oxidation by sulfiting (5-8 g/hl). In theory, clarification seems less important in rose winemaking than in white winemaking, but this practice refines wine aroma and diminishes the iron concentration. Must can be treated with bentonite. Anthocyanin fixation results in a slight color decrease but it is brighter and less sensitive to oxidation. It is not advisable to use bentonite with pectolytic enzymes. 

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. 

The success of such rose winemaking is based above all on the use of healthy and perfectly mature quality grape varieties. Malolactic fermentation is a general practice and becomes all the more necessary as the maceration phenomenon increases. A low acidity softens the tastes of the tannins. 

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