Ch 8 - White and Sweet Winemaking Flashcards
What might a winemaker do to limit skin contact in the initial stages of the winemaking process for white/sweet wine? Why is this process potentially advantageous?
Rather than crushing, letting free run separate and then sending the crushed grape mass to the press, the winemaker may might load the press with whole bunches of uncrushed grapes. This process is gentle, reduces the risk of oxidation and can lead to more purity and delicacy
Why might a winemaker choose to keep the juice in contact with the skins when making white/sweet wine? What are two important factors to ensure when doing this?
For some aromatic varieties this will increase flavour, intensity and texture. Must occur at low temperature to inhibit fermentation and should only last a few hours.
What is the negative impact of fermenting untreated/unclarified juice?
It will contain fragments of cells from skins and pulp which develop unpleasant aromas and the fermentation may stop prematurely.
When does the juice need to be clarified?
Before fermentation begins.
What methods can be used for clarification? Why might some winemakers leave fragments or solids in the juice?
Settling, centrifugation, fining, filtration. It is thought by some that leaving some fragments or solids protects the juice from oxidation however the risk of unpleasant aromas forming means it is rarely done for wines intended to show pure varietal character.
What is the optimum temp for fermentation of white wine? What happens outside this range?
12-22 degrees celsius. If it is too cold then pear drop aromas may form and it will fail to capture varietal fruit characters. Too high and it will encourage more complex, non fruit aromas but at the risk that varietal fruit characteristics will be lost.
Discuss the different fermentation vessels and how they may interact with temperature control.
Stainless steel ones usually have temp control mechanisms to prevent temps running too high. In barrels, it is not as easy to control temp but their smaller size and the fact they’re normally housed in cool cellars means they tend to dissipate heat effectively. They still tend to run at the higher end of the temperature range.
What are the main choices a winemaker faces post-fermentation (regarding storage and maturation)?
- to mature in oak or stored in inert vessels with or without oak staves/chips.
- to use lees to add texture and flavour
- to allow or block MLF
Why might a winemaker choose to blend wines?
May assist to improve consistency, enhance balance and create a certain style, like a house style. Many white wines are focused on primary fruit flavours so blending may be aimed at consistency rather than complexity. For non-aromatic varieties though, like Chardonnay where lees contact, MLF and oak treatment may be used, blending may be employed to achieve a more complex style.
What is the aim of fining or filtration? Why might this be particularly important with white wines?
To improve the clarity and stability of the wine. The light colour of most whites makes haze or sediment very apparent. Those with some residual sugar are also at risk from microbiological infection in which case they maker may wish to sterile filter to remove yeast or bacteria.
What grape varieties tend to be made into high volume, inexpensive white wines? What makes these grapes suited to such wines?
Neutral in flavour, Chardonnay and Pinot Grigio are classic examples. Restrained varietal character means they appeal to a wide range of consumers. Both are easy to ripen, especially in warm climates but may have insufficient acidity at harvest which will need to be corrected in the winery.
Sauvignon Blanc is sometimes used but rarely at lowest price point. Vigorous grapevine - high yields but herbaceous flavours will dominate if fruit is underripe.
What would a high volume chardonnay style be like?
Unoaked, pure fruity flavours like peach and melon OR oaked, giving vanilla and toast. Both may contain residual sugar to make more palatable to range of consumers.
What would a high volume Pinot Grigio style be like?
Unoaked, with light pear drop aromas and flavours, light body and medium acidity.
What would the winemaking choices be for high volume whites?
Careful handling to avoid oxidation - SO2 will be monitored and juice and wine handled protectively. Grapes will be destemmed and crushed, then pressed. Acidification may be a necessary adjustment for those grown in warm and hot regions where grapes are particularly low in acidity. Chardonnay in particular is flat and flabby without adequate acid.
Juice clarified to ensure fruity flavours retained prior to fermentation. Settling using gravity too slow - so may use centrifuge or filter to speed it up.
Stainless steel tanks for fermentation at cool temps to preserve primary fruit aromas. Vital especially for lower flavour grapes such as PG at high yield.
Commercial yeast used to ensure reliable, quick fermentation.
What is important when growing Premium Sav Blanc? Consider climate.
Sav blanc is early ripening - suited to cool climates where temps will help retain the refreshing characteristics and natural high acidity.
