Pomace Fermentation Management (L4,5,8)

Question 3

What is the primary objective of pomace winemaking?

Answer 3

To achieve the desired wine style through careful grape selection, processing, and fermentation management.

Question 4

What are the key differences between pomace and pulp winemaking?

Answer 4

The most significant differences are:
* Fermentation temperature: Pomace fermentation is warmer.
* pH and acidity: Skins impact pH and acidity.
* Monitoring requirements: Due to the cap.

Question 5

List the core principles of pomace winemaking.

Answer 5

• Select red (white) skinned grapes.
• Process the grapes into must.
• Manage the ferment.

Question 6

What are the key steps in pomace winemaking?

Answer 6

• Pre-fermentation processing: De-stemming and crushing.
• Alcoholic fermentation: With skin contact.
• Draining and pressing.
• Malolactic fermentation (MLF).

Question 7

What is the purpose of de-stemming in pomace winemaking?

Answer 7

To remove bitter tannins, high potassium levels, and high water content from the stems.

Question 8

Why is crushing important in the winemaking process?

Answer 8

To liberate juice for the yeast, increase phenolic extraction, and homogenize/aerate the must.

Question 9

Fill in the blank: Pomace fermentation is generally carried out at _______ temperatures than pulp fermentation.

Answer 9

warmer

Question 10

What temperature range is typical for pomace fermentation?

Answer 10

20°C - 30°C.

Question 11

How does the presence of skins during fermentation affect pH and acidity?

Answer 11

Skins lead to higher levels of potassium ions, affecting pH and acidity.

Question 12

What issues can elevated pH levels in pomace wines cause?

Answer 12

• Poor colour
• Reduced microbiological stability
• Increased susceptibility to oxidation
• Reduced efficiency of sulphite

Question 13

What is the role of the cap in pomace winemaking?

Answer 13

The cap is a reserve of tannins, colour, flavour, and aroma chemicals.

Question 14

True or False: Cap management involves periodic saturation with wine.

Answer 14

True

Question 15

What are the potential consequences of poor cap management?

Answer 15

• Insulation leading to high temperatures
• Decreased extraction
• Potential spoilage

Question 16

What does careful management of temperature, pH, and the cap help achieve in pomace winemaking?

Answer 16

Optimal extraction and avoidance of potential spoilage.

Question 17

What is the main challenge of managing temperature in red (orange) ferments?

Answer 17

It is more complicated compared to white ferments.

Question 18

Fill in the blank: The _______ is predominantly composed of skin fragments in pomace winemaking.

Answer 18

cap

Question 19

What can be a result of high initial pH in relation to bitartrate precipitation?

Answer 19

It can significantly increase pH.

Question 20

What is the importance of maceration in pomace winemaking?

Answer 20

It is crucial for phenolic extraction.

Question 21

List some potential benefits of adding stems back during fermentation.

Answer 21

• Reduce cap compaction
• Aid phenolic extraction
• Add tannin in certain vintages.

Question 23

What are polyphenols?

Answer 23

Key compounds in pomace wines that influence flavor, color, and stability

Polyphenols are important for the quality of wine and are extracted during fermentation.

Question 24

What are the two main types of phenolics?

Answer 24

• Non-flavonoids
• Flavonoids

Non-flavonoids include simpler phenolics like benzoic and cinnamic acids, while flavonoids include catechins, resveratrol, and anthocyanins.

Question 25

What role do anthocyanins play in wine?

Answer 25

They provide red color to wines ## Footnote Anthocyanins are critical for the color profile of red wines.

Question 26

What are tannins known for in winemaking?

Answer 26

They contribute to astringency and mouthfeel in wines ## Footnote Tannins are polymerized catechin molecules that enhance the structure of wines.

Question 27

What happens when anthocyanins react with sulphite?

Answer 27

Bleaching occurs ## Footnote This reaction can affect the color stability of the wine.

Question 28

What is the effect of fermentation temperature on phenolic extraction?

Answer 28

Higher temperatures increase the breakdown of skin cells and dissolution of phenolics ## Footnote Red ferments are conducted at higher temperatures than whites for optimal extraction.

Question 29

What is cap management in winemaking?

Answer 29

Techniques used to increase skin/wine contact for enhanced phenolic extraction ## Footnote This includes frequency, duration, and intensity of cap management.

Question 30

How does fermentation duration affect wine style?

Answer 30

Shorter skin contact times produce light, easy-drinking reds; longer times produce full-bodied reds ## Footnote Extended skin contact can lead to tannin softening.

Question 31

What is the significance of press wine?

Answer 31

It releases significant phenolic material and has different characteristics than free-run wine ## Footnote Press wine may contain more color and phenolics.

Question 32

Name some techniques used with pomace wines.

Answer 32

* Thermovinification * Flash Dente * Cryoextraction * Enzymes * Yeast choice * Pulsed electric field * Microwave * Saignee or Bleeding * Whole berries * Stem inclusion * Skin inclusion (Ripasso) * Oak chip inclusions * Exogenous tannin addition * Co-pigmentation ## Footnote These techniques can influence the final characteristics of the wine.

Question 33

What is the 'Art' vs. 'Science' debate in winemaking?

Answer 33

It involves balancing scientific principles with intuitive decision-making ## Footnote Many winemakers rely on experience and instinct in addition to scientific methods.

Question 34

True or False: Tannins are responsible for the sweetness in wines.

Answer 34

False ## Footnote Tannins contribute to astringency, not sweetness.

Question 35

Fill in the blank: Much of the art of pomace winemaking is in controlling the _______ and development of grape phenolics.

Answer 35

extraction ## Footnote This control is crucial for achieving desired wine characteristics.

Question 36

What is the core principle of pomace management in winemaking?

Answer 36

To understand and control the extraction of compounds from the pomace to achieve desired wine characteristics.

Question 37

What are the three main goals of pomace management outlined in the lecture?

Answer 37

* Define the goals of pomace management * Outline key decisions in pomace management * Assemble a framework for evaluating pomace management.

Question 38

How does pressing affect wine quality?

Answer 38

Press wine is usually different from free drained wine; blending them can influence final wine quality.

Question 39

What impact does acidity/pH have during winemaking?

Answer 39

It affects colour, taste, micro-organisms, oxidation, and extraction.

Question 40

What is the significance of yeast strain selection in winemaking?

Answer 40

It influences colour, polyphenol and polysaccharide levels, and aroma/flavour development.

Question 41

What is Malolactic Fermentation (MLF) and its impact?

Answer 41

MLF impacts pH, TA (Titratable Acidity), colour, and aroma/flavour.

Question 42

Why is seed removal important in pomace management?

Answer 42

It reduces tannin extraction and the risk of seed damage, especially after alcohol production begins.

Question 43

What are the effects of stalk inclusion in pomace?

Answer 43

* Increases polyphenols * Increases potassium and water * Decreases colour and ethanol.

Question 44

What is the purpose of Saignée/Bleeding in winemaking?

Answer 44

It increases skin/seed concentration, colour, and polyphenols.

Question 45

What is the process of Skin Inclusion (Ripasso)?

Answer 45

Re-fermenting wine on skins from previous fermentations adds colour, polyphenols, and flavours.

Question 46

Define co-pigmentation in winemaking.

Answer 46

Co-pigmentation involves the interaction of pigments with other compounds to enhance colour and stability.

Question 47

How does oxygen exposure benefit winemaking?

Answer 47

It is important for sterol production, ethanol tolerance, nitrogen uptake, and possibly polyphenol stabilisation.

Question 48

What role do exogenous enzymes play in pomace management?

Answer 48

They can increase the rate and total extraction of compounds.

Question 49

What is the effect of exogenous tannin addition?

Answer 49

They can have antioxidant and co-pigmentation effects but should be used cautiously.

Question 50

How does the choice of fermenter influence winemaking?

Answer 50

It affects cap depth, wet/dry proportions, pump-over coverage, thermal mass, oxygen contact, and overall chemistry.

Question 51

What are some techniques that contribute to skin degradation?

Answer 51

* PEF (Pulsed Electric Field) * Cryoextraction * Thermovinfication * Flash detente.

Question 52

Why are polyphenols important in winemaking?

Answer 52

They influence colour, taste, and overall wine quality.

Question 53

What does the term 'system dynamics' imply in the context of pomace management?

Answer 53

It suggests that pomace management should be viewed as a complex, interconnected system.

Question 54

Fill in the blank: The ultimate goal of pomace management is to optimise the extraction of _______ while minimising the extraction of undesirable components.

Answer 54

[desirable components]