Wine Flashcards
Is fermentation done before or after pressing for white and red wine respectively?
After and before respectively.
Can u make white wine from red grapes?
Yes. As long as the juice is white.
What are the three techniques to obtain rose?
- Direct pressing -> If red grapes have a lot of color they can be pressed and treated as white wine. No extraction from skin is performed here.
- Maceration -> if color is not enough then the grape can be macerated with the skins to extract more color. The wine is then treated as white.
- Saignee -> during fermentation of red wine, some juices are removed to increase skin/juice ratio. This juices that are removed and fermented into rose.
Why destemming is not necessarily important for white wine?
Because pressing is performed immediately. This does not allow the bitter substance from the stem to extracted.
Why maceration should be conducted below 15 C?
To limit microbial growth
What is the purpose of maceration and what is important for white wines?
Maceration allows the skin and juices to soak for a time period. Aromas are extracted. It is important that for white wine the skin does not have much color.
Why is maceration conducted during/after fermentation for red wine? And is it always performed
It requires ethanol in order to extract color which only comes with fermentation. Maceration is always conducted for red wines.
Which juice is perceived as higher quality? Free run juice or pressed juice?
Free run juice as it contains less tannins, polyphenols, tanning and other undesired products.
What is the purpose of addition K2S2O5 (Potassium metabisulfite)?
Because it reacts to give sulfur dioxide which reduces unwanted bacteria and prevents growth of wild yeast.
Is must clarification performed for white or red wines?
White wines. Removal of proteins and other substance which can caused undesired flavors. Process is performed before fermentation.
When the acidity of the wine is too high which fermentation is conducted and what is the reason of pH reduction?
Malolactic fermentation -> Malic acid is converted into lactic acid and because malic acid has two acidic groups and lactic acid has only one, the pH decreases.
Why is white wine fermented at lower temperature compared to red wines?
Because this allows more aromas to stay in the wine such as esters. On the other hand slightly higher temperature are used for red wine as it allows more color and flavor to be extracted.
What alcohol percentage does 16.8-18 gram of sugar per liter make under fermentation?
1% ethanol
Why red wines are aged in oaked barrels?
Because micro oxidation occurs which transforms tannins into softer tannins. Furthermore aromas are extracted from the barrels.
What is mainly found in the skin of the grapes?
Mostly the aromas and the anthocyanin (color)
