Fermentation and Still White Wine Production

Question 1

The science of winemaking is known as

Answer 1

Enology

Question 2

The prefermentation portion of winemaking is often broadly referred to as the

Answer 2

Crush

Question 3

Methods winemakers use to protect just picked grapes from degrading are

Answer 3

Covering them,
cooling them
using sulfer.

Question 4

SO2 is the combination of

Answer 4

Sulfur and oxygen to become Sulfur Dioxide

Question 5

What does Sulfur Dioxide do when added to grapes or juice?

Answer 5

Inhibits the growth of yeast and bacteria which reduces the chance of premature fermentation. Also prevents the juice from oxidizing and turning brown.

Question 6

The first step in grape reception is called

Answer 6

Sorting

Question 7

List the pre-fermentation steps of white wine production.

Answer 7

Sorting
Crushing/Destemming
Pressing
Must Adjustment
Settling

Question 8

Define whole berry or whole cluster pressing.

Answer 8

Rather than de-stemming and crushing the entire bunch are pressed together.

Question 9

What is the difference between crushing and pressing?

Answer 9

Crushing is piercing the skins of the grapes, pressing is the compressing of the grapes and solids several times.

Question 10

How can a “cold soak” benefit a white wine?

Answer 10

With the skins macerating with the juice more aromas and phenolics are extracted. This is good for the more aromatic grape varieties.

Question 11

How long does a “cold soak” last for a white wine.

Answer 11

No longer than 24 hours.

Question 12

What is free run juice?

Answer 12

the first, large amount, of juice that drains out from the press.
-highest quality, rich in sugar and low in tannins

Question 13

What is the cake of dry compressed skins and seeds called?

Answer 13

Pomace

Question 14

Two examples of pomace brandies are

Answer 14

Grappa and marc

Question 15

Grape juice that’s destined for fermentation is called

Answer 15

must

Question 16

What is acidification?

Answer 16

The addition of tartaric acid in the must needed for balance.

Question 17

What is chaptalization?

Answer 17

The addition of sugar in the must for wines that might not end up with enough alcohol. Not for sweeter wines!

Question 18

A chaptalized wine is sweet. T or F

Answer 18

False

Question 19

What are some other methods of raising or lowering acid or sugar in the must?

Answer 19

Adding water to dilute, adding grape juice or concentrate.

Question 20

The process of letting the must settle before fermentation is called

Answer 20

Juice settling.

Debourgage in French

Question 21

The smaller molecules that remain after the yeast cells have split apart the sugars are

Answer 21

Ethyl alcohol and carbon dioxide

Question 22

What percentage of the grape sugars are converted into alcohol before fermentation stops?

Answer 22

90%

Question 23

List of vessels to ferment white wine?

Answer 23

Stainless steel - inert
60 gallon oak barrels
large wooden casks
concrete vats

Question 24

Oak barrels are used in white wine fermentation to add

Answer 24

Complexity, oak flavors and downplay fruit aromas

Question 25

What two methods do winemakers use to keep fermentation from starting before they are ready?

Answer 25

Addition of sulfur and/or refrigerating the must.

Question 26

The yeasts mainly used in winemaking are strains of

Answer 26

Saccharomyces cerevisiae

Question 27

Why are different strains of yeast used?

Answer 27

Different strains impart different flavors aromas, speed or slow the fermentation process or achieve a certain level of alcohol.

Question 28

What the optimal temperature for white wine fermentation:

Answer 28

50 - 60 F | 10 - 16 C

Question 29

Cooked fruit or applesauce aromas in white wines occur at high or low fermentation temperatures?

Answer 29

High

Question 30

At what temperature will yeasts die and fermentation will stop?

Answer 30

100 degrees 38 C

Question 31

A normal white wine fermentation will take how long?

Answer 31

Several days to several weeks

Question 32

At what alcohol level will fermentation halt?

Answer 32

14%

Question 33

Yeasts die at what alcohol level?

Answer 33

14%

Question 34

A typically produced dry white wine will have an alcohol content of

Answer 34

12 - 14%

Question 35

What ester is created as a byproduct of a white wine MLF and what aroma does it impart?

Answer 35

Diacetyl - a "buttery" aroma

Question 36

What white wine benefits from MLF?

Answer 36

Chardonnay

Question 37

What is the term for the sediment at the bottom of the fermentation tank or barrel.

Answer 37

Lees

Question 38

The method of gentle clarification is called

Answer 38

Racking

Question 39

Why would a winemaker allow a white wine to rest sur lies?

Answer 39

The dead yeast cells impart a creamy texture and increased complexity to the wine.

Question 40

What is battonage?

Answer 40

The french term for stirring of the lees.

Question 41

After fermentation is complete, additional sulfur may be added to post fermented white wine why?

Answer 41

prevent microbial spoilage prevent browning prevent further fermentation (for sweet wine)

Question 42

Methods of clarifying white wine before bottling are:

Answer 42

Racking Fining Filtering Centrifuge

Question 43

Define Fining?

Answer 43

Inert material that falls through wine, attracting and binding with unwanted material as it settles. - racked off - agents include gelatin, egg whites, bentonite clay

Question 44

What is sterile filtering?

Answer 44

Technology that filters out all microbes. (yeast/ bacteria) that could cause spoilage

Question 45

Wine diamonds are called?

Answer 45

Tartrates

Question 46

To prevent tartrates from developing in a white wine bottle what process is used before bottling?

Answer 46

Cold stabilization

Question 47

Cold stabilization occurs at around what temperature?

Answer 47

25 degrees

Question 48

How long will a cold stabilization last before the white wine is racked and bottled?

Answer 48

1 - 3 weeks

Question 49

List the post-fermentation steps in white wine production.

Answer 49

``` MLF (if desired) Lees contact (if desired) Sulfur addition Clarification Barrel Aging (if desired) Blending Cold Stabilization (if desired) Bottling ```

Question 50

The French term for juice settling is

Answer 50

Debourbage

Question 51

define a bladder press?

Answer 51

inflate a large balloon with air or water to squeeze grapes to release juice advantage: flexibility, reduced risk of crushing seeds or bursting the skin

Question 52

if necessary what is added to must to reduce acid?

Answer 52

potassium | or calcium bicarbonate

Question 53

What is the term for putting cultured yeast into must to imitate fermentation?

Answer 53

Inoculation

Question 54

define Malolactic Fermentation?

Answer 54

- conversion process simultaneously with or after primary (alcoholic) fermentation - carried out by a particular strain of lactic acid bacteria - resulting in changing tart, green apple flavors for creamier characteristics

Question 55

What is the purpose of clarifying a wine?

Answer 55

to remove any solids that are in suspension causing a murky appearance.

Question 56

How is racking wine accomplished?

Answer 56

action of gravity to let settle particles on the bottom over a period of time then wine is drawn off the sediment and moved to a fresh container -may leave some microscopic particles (tannin or proteins) left in wine

Question 57

define filtering wine?

Answer 57

straining the wine through a barrier with very fine openings trap any particles over a certain size -eliminate contaminants like bacteria

Question 58

describe what barrel aging does for a wine?

Answer 58

- slow oxidation, adds complexity - resulting flavors: vanilla, oak, wood, coconut, toast, other - goal of a heavier, fuller-bodied style - Chard, Sauv Blanc called out white wines

Question 59

Define blending?

Answer 59

mixing wine from different: - vineyards - variety - vintages - production methods

Question 60

What is the goal in blending wines?

Answer 60

achieve a consistent flavor profile year after year -develop complexity or balance create a particular style of finished wine