Chapter 5 - Fermentation and Still Wine Production Flashcards
What is the main purpose of adding S02 to either the unfermented grapes or at any process through bottling in wine production?
S02 inhibits the growth of both yeast and bacteria, thereby reducing the likelihood of premature fermentation and spoilage.
What are the steps in the wine making process (please list)
- Sorting
- Crushing & Destemming
- Pressing
- Must Adjustments
- Juice Settling
- Initial Fermentation
- Malolactic Fermentation
- lees Contact
- Sulfur Addition
- Clarification
- Barrel Aging
- Blending
- Cold Stabilization
- Bottling
Define the term “cold soak”
A period of aqueous (as opposed to Alcoholic) extraction prior to fermentation that is accomplished by maintaining a temperature low enough to prevent the start of fermentation.
Describe the term “Free Run”
This is all of the juice that flows freely from the freshly picked grapes before they are pressed.
The weight of the grapes stacked on top of each other causes the them to burst.
The highest quality juice, rich in sugar and low in tannin.
What is a bladder press?
A modern press that uses balloon presses filled with air that is gentle and doesn’t extract as much tannin/phenolics
The result is more usable juices
Define the term “pomace”
The cake of dry compressed skins, and pips (seeds) that remain after the final pressing.
Often composted or put back to the vineyard to improve soil health.
It can also be used to make pomace brandies known as marc or Grappa.
Define the term “Marc”
A pomace Brandy made from the spent skins and seeds.
what type of Acid is added to wine for Acidification?
Tartaric Acid
What is RGCM? What is its purpose?
RGCM is Rectified Grape Must Concentrate, which is grape juice or concentrated grape sugar. This is used to increase the sugar levels when the grapes may not have gotten ripe enough during the season.
How is the addition of RGCM different from Chaptalization?
adding pure sugar to the must before fermentation vs adding concentrated grape sugar.
The goal for both is to achieve the proper sugar levels to make a specific wine style with out having sweet wines. The sugar is to all be converted to Alcohol.
Define the term “Debourbage”
This is the settling of the freshly pressed juice.
you may be trying to allow any solids to settle out or you may be adding more juice from the next pressing to the juice.
define the term “Inoculation”
Addition of Commercially grown yeast in order to start fermentation.
Usually done because of the guarantee of the desired outcome
what is the name for the most common yeast strain used in winemaking?
Saccharomyces Cerevisiae.
- If your goal is to retain delicate floral and fruity aromas during winemaking, what is the preferred Temperature to achieve this?
Between 50 and 60 Degrees Fahrenheit
What is a reason that a winemaker would intentionally stop fermentation?
In order save some sugar in the wine if you are trying to achieve off dry or medium dry wines. This could be fore dessert and fortified wines as well.
What is the the ester that is known to create the buttery characteristic in wine?
Diacetyl.
Describe the process of Malolactic fermentation.
This is a form of fermentation that is more of a transformation of sharp malic Acid into a softer rounder buttery acid known as Malic Acid.
It also results in a more microbially stable wine.
What type of wine might a winemaker decide to avoid Malolactic Fermentation?
Fragrant wines, with light body, and crisp acidity
Why would you want to do the process of Batonnage during the winemaking process?
Battonnage is the process of lees stirring. Having the spent lees in contact with the wine will add texture and body to the wine as well as some complexity yeasty aromas.
After fermentation is complete, why might you want to add sulfur to the wine?
to decrease the chance of microbial spoilage or browning in the finished wine.
This is important if there is any residual sugar left, as you may end up with unwanted fermentation after bottling.
define the term “Racking”
The most basic form of clarification. Here you allow the suspended matter to settle to the bottom of the fermentation vessel. The wine is then carefully drawn off in to a clean vessel.
The use of gravity.
Racking can be done numerous times throughout the process.
This does not capture all particles, more clarification may be needed.
Define the term “Fining.”
An inert material that has an affinity for certain pariculates is stirred into the wine, attracting and binding with the unwanted material as it settles to the bottom.
Both the fining agent and sediment are then separated from the wine by racking.
geletin
egg white
Both of these bind with and removed excessive tannin, and bentonite clay which attracts and removes proteins.
Define the term “Filtering”
straining the wine through a barrier in order to trap particulate.
Modern Filtering is known as sterile filtering which can eliminate contaminates as small as bacteria (also yeast)
The Con:
You may remove some desirable flavor molecules. aka this process works too well.
Define the term “Centrifuge.”
The use of accelerated gravity through the use of modern lab equipment. This will separate the solids from the liquid.
Why might you barrel Age your wines?
Aging wine in oak barrels allows for a slow oxidation that changes the wine and adds complexity.
If the wood is new: add touch of vanilla, oak, wood, coconut, toast, or other aromas.
Why might you blend your wines?
Just before bottling, many different vats, or vessels might be blended together in order to create a final product.
This can be used to create a specific flavor profile, or it could be multi vineyard, plot, or vintage.
consistency or complexity and balance.
