Class 4: From Barrel to Bottle, Sweet and Fortified Wine Production Flashcards
HOST 9111 - Methods of Wine Production
What happens in the vineyard during Pre-Harvest Prep?
- Scan for fungi or insect pests
- Continue spray regime
What happens to berries during Pre-Harvest Prep?
- Sample regularly
- Test brix, acid and nitrogen
What happens at the winery during Pre-Harvest Prep?
- Prepare equipment
- Stock lab materials and supplies
What does winemaker measure in grapes?
- Acidity levels
- Brix
- Nitrogen
When are grapes analyzed?
Before, during and after harvest
What is élevage?
The maturation and ageing process post alcoholic fermentation.
Period fermentation and bottling.
What is the maturation period? Note: elevage seems to be time between post fermenting and bottling. Ageing seems to refer to the time in bottle.
Starts in winery and carries on in bottle with the consumer.
What kinds of vessels can be used for élevage?
All kinds
Vessels for fermentation and élevage can be different
What styles of wine is élevage used for?
All styles
How long does élevage last for?
Can be short of long, depending on style and colour
When can MLC occur?
Before or during elevage (my mistake - had put fermentation which is wrong)
What happens during élevage?
- Floral fruity to savoury, earthy and herbal
- Colours shifts
- Tannins soften, astringency fades
What are ideal storage conditions?
Cool
Consistent in temperature, Slightly humid
What factors impact wine during élevage?
LARTS
- Ageing vessel: size and material
- Lees management (fine lees, use and frequency of bâtonnage)
- Racking (frequency; high O2 exposure)
- Topping protocols
- Sulfur additions
What role does oxygen play during élevage?
Amount of exposure can have huge impact on final wine.
Name 3 types of ageing vessels.
- Concrete
- Oak
- Stainless steel
Describe the concrete vessels used for elevage
- Greatly limits oxygen
- Thermal stability
- Oval shapes = automatic lees stirring
- Easy to clean
- Eco friendly
Describe oak vessels used for élevage.
- Slow oxygen ingress
- Can contribute flavour and tannin
- Traditional; luxury
- Can allow lees contact - control amount with bâtonnage
- Hard to clean
Describe the impact stainless steel vessels have on élevage.
- Oxygen tight
- Temperature control
- Any size
- No flavour / texture
- Allows lees contact but limits suspension
- Easy to clean
What are the pros of bâtonnage?
Introduces some oxygen
Flavour / texture
Lees can scavenge excess oxygen
What are the cons of bâtonnage?
Can introduce too much O2
Can form unwanted aromas if starved of oxygen
Can over-soften
What are the pros of resting on lees (no bâtonnage)
Less O2 introduced
Can still protect from excess oxygen
Some flavour
Not too much texture
What are the cons of resting on lees (no bâtonnage)
Lees can produce off-aromas if not enough O2
Solve by racking and return which oxygenates
What is racking?
Moving wine from one vessel to another
What does racking do to aromas?
Manages oxygen exposure which in turn influences development of sulfur-based aromatics
Skip. Dumb question.
Can racking be done reductively?
Yes.
Inert gas injected into the sealed container
Pressure pushed liquid out
What is the headspace at the top of the barrel called?
Ullage
What is topping?
Adding wine saved in SS to wooden barrel to replace any wine that has evaporated out
Why is topping important?
As wine evaporates out of the barrel, the wine is exposed to more oxygen in the increasing large ullage
Topping up the barrels reduces the ullage and oxygen exposure
Does topping up expose the wine to oxygen?
Yes.
Removing bung to top up the barrel exposes the wine to more oxygen
Choice: more O2 by allowing wine to evaporate, or more O2 when topping up?
What does sulfur do?
Protects the wine form bacterial spoilage, oxygen and yeast-based organisems
What form of SO2 protects wine
Molecular SO2
(part of the “free” SO2)
How does pH affect SO2 usage?
As wine becomes less acidic (higher pH), more SO2 needed
What does oxidation do to SO2?
Free SO2 decreases slowly in bottle over time
What works better against bacteria - yeast or SO2?
SO2 more effective against bacteria than yeast
What does SO2 do to tannin?
SO2 bonds with tannin and affects perception
What is assemblage?
Brings together the harvest
Combines the wine in a single location in anticipation of bottling
What are the steps in assemblage?
- Each barrel sampled
- Wine from selected barrels are racked, then sent to blending tanks
- Wine is bottled
What are the financial implications regarding assemblage?
Not all barrels will produce a good wine
These wines are:
* Bottled under a declassied label or put in cheaper bottles in the house’s line
* Sell it as bulk wine
What is a fining agent?
Fining agents bind to specific types of proteins and form clumps with precipitate to bottom of the barrel
What does fining do?
Fining assists in clarifying the final wine
Aids stability of wine in the bottle
Remove excess, bitter tannins
What happens if too much fining agent is used?
Too much fining will strip away character
What are some common fining agents?
- Bentonite
- Clay
- Isinglass
- Albumin
- Gelatin
- Casein
Sometimes a ferment may struggle or be reductive in a negative way. This can produce off-smells. What will remove it?
Copper fining
What does filtration do?
Physical filters remove larger particles and unwanted microbes and yeasts
Clarify wine
What are the 2 big categories of filters?
- Depth filters
- Absolute filters
Describe depth filtration
Pads filled with diatomaceous earth (kieselguhr) filter larger particles out
“Depth” meaning the particles pass through a very thick filter and the particles are filtered out in the “depths” of the filter
Describe surface or absolute filtration
Screen filters with a set pore size
Everything larger than the pore cannot pass and remains on the “suface” of the filter
Sterile filtration: absolute filtration where everything is filtered out (10 microns)
What is cold stabilization?
Chilling the wine to precipitate tartrates and rack them out
How is microbial stability achieved?
Addition of a fining agent that inhibits the growth of microbes and yeast.
SO2 is most effective and versatile
In what kind of vessel is most high-end wine bottled?
In bottles
Gold standard
Inert, durable
Name 4 other ways to package wine.
- Tetrapak
- Beg wine
- Wine keg
- Cans
