Red wines and Rose wines Flashcards
(55 cards)
What is the focus of many choices in red winemaking?
The extraction of anthocyanins, tannins, and flavors from grape skins.
What are three factors that affect extraction?
- temperature
- time on skins (and mixing of skins with juice/wine)
- medium in which extraction takes place (tannins more in alc, anthocyanins more in water)
What makes anthocyanins more stable, and what speeds this reaction?
- Combination with tannins
- O2 facilitates this combination
What are two ways in which anthocyanin can be lost if not bound to tannins?
- SO2 additions (which bleach it)
- adsorption by lees (i.e., anthocyanin can form a film on lees)
What are three uses of heated maceration?
- for making inexpensive or mid-priced wines consumed shortly after production
- a blending component for higher quality wines (bringing juicy/fruity flavors)
- subsequently fermented on the skins for some time to extract more tannins
What are four reasons to use cap management techniques?
- Extraction would gradually stop, as juice around skins would become saturated
- A dry cap would permit acetic acid bacteria to grow (as they need O2)
- Helps aerate the must to avoid reductive sulfur compounds
- Helps distribute heat produced by ferm
What are the four variables can be altered in cap management?
- Technique of cap management
- Frequency
- Timing of mixing (beginning: more color, less tannin; end: more color, less tannin)
- Temperature
What are five methods of cap management?
- Punching down
- Pumping over
- Rack and return
- Ganimede tanks
- Rotary fermenters
- Describe punching down
- When done manually, what vat is required and what is the cost?
- What varieties is it used on?
- A plunger is used to submerge the cap
- Small vats when done manually
- Labor intensive when done manually, so used with low-vol premium wines
- Gentle, so done on a range of varieties
- Describe pumping over
- Is it gentle? Why?
- Is it aerobic or anaerobic?
- About 1/3 - 1/2 of the juice/wine from near the bottom is sprayed over the cap of skins
- It is very gentle, as the juice just extracts as it passes through the cap, rather than breaking it up
- It can be aerobic (lots of splashing) or anaerobic (if in a closed vessel)
As to pumping over:
* What other cap management techniques are used with it, and why?
* What varieties, price points, and qualities is it used for?
- It’s so gentle that it needs to be done with punching down or rack and return for sufficient extraction
- Done with all black varieties, at all price points and qualities
- Describe rack and return
- How does it compare to other cap management techniques?
- Juice pumped into another vessel, which makes the cap drop and get broken up. Juice then sprayed on top of cap.
- More extractive than pumping over or punching down–can only be used 1-3 times
Rack and return:
* What varieties is it used for?
* What are the cost components?
- Reds with me to high levels of flavor/color/tannins desired (e.g., Cab Sauv or Syrah)
- Labor (cannot be automated) and requires a separate, clean vessel
- Describe use of Ganimede tanks
- How does it compare to other cap management techniques?
- Specialized tank that bubbles CO2 up through must/wine. Pressure builds until the cap bursts.
- Extractive like rack and return
Ganimede tanks:
* What varieties is it used for?
* What are the cost components?
* What is a variation?
- Reds with me to high levels of flavor/color/tannins desired (e.g., Cab Sauv or Syrah)
- Tanks are slightly more expensive, but can be automated
- O2 can be used to increase O2 during ferm
- Describe rotary fermenters
- How does it compare to other cap management techniques?
- Horizontal, closed, stainless steel tank that rotates, and internal blades break up cap
- Very effective at extracting
Rotary fermenters:
* What varieties/wines is it used for?
* What are the cost components?
- Reds with me to high levels of flavor/color/tannins desired (e.g., Cab Sauv or Syrah)
- High-vol, inexpensive or mid-priced (as it is not gentle and difficult to control level of extraction)
- Easy to automate, but equipment costs are high
Other than cap management, what are two other ways to increase color, flavor, and/or tannins of a red wine during ferm?
- Must concentration (via saignée)
- Co-fermentation
- Describe co-fermentation
- Two potential advantages?
- One potential disadvantage?
- fermenting a small
proportion of white grapes (typically up to 5 per cent) within a red wine fermentation
Potential advantages:
* can increase color intensity and stability through binding of white wine phenolic compounds with anthocyanins
* can contribute aromas (like terpenes in Viognier)
Disadvantage: Research shows mixed results, and too much can lead to dilution of color
What 4 effects does lack of oxygen have on whole berry/bunch ferm?
- Grapes change from aerobic respiration to anaerobic metabolism (converting some sugars to alc)
- Malic acid is broken down to create ethanol (reducing malic acid by up to 50%)
- Glycerol increases, adding texture
- Distinctive aromas created (kirsch, banana, bubble gum, cinnamon)
- What is an important requirement for using whole bunch ferm?
- What varieties are not often used for whole bunch ferm?
- Stems of bunches must be fully ripe (else they would give unpleasant green flavors and bitter tannins)
- High tannin varieties, like Cab Sauv
What is the cost of using whole berry/bunch ferm?
It is not costly, but other parts (e.g., hand harvesting) may be
What are the three forms of whole berry/bunch ferm?
- Carbonic maceration
- Semi-carbonic maceration
- Whole berries/bunches with crushed fruit
Describe carbonic maceration in 6 steps
- only whole, uncrushed bunches in vessel filled with CO2
- intracellular ferm produces 2% alc
- then either (i) grapes crushed or (ii) grapes start to split and grapes release juice
- juice drained immediately, and pressed
- free run and press juice usually blended
- yeast completes ferm off skins