18. Specific options for red winemaking

Question 1

What 3 factors affect extraction in red wine?

Answer 1

• Temperature
• Time on skins
• The medium in which it takes place

Question 2

How does temperature affect extraction?

Answer 2

higher temps result in greater extraction

Question 3

How does times on skins affect extraction?

Answer 3

generally, the longer the juice/wine remains in contact with the skins the great the extraction. The more the skins are mixed through the juice, the greater the extraction

Question 4

How does the medium that extraction takes place affect it?

Answer 4

Tannins are most soluble in alcoholic solutions

Anthocyanins are most soluble in aqueous solutions (grape must)

Question 5

What are anthocyanins?

Answer 5

The source of color in young red wines.

Question 6

How can the color that anthocyanins provide be altered?

Answer 6

• altered or lost in the process of different winemaking procedures, such as lees aging or additions of So2
• become paler over time

Question 7

Anthocyanins alone are unstable. How do they become more stable?

Answer 7

Combining with tannins. Oxygen facilitates this reaction, therefore winemaking processes that encourage gentle oxygenation of the wine can help promote color stability.

Question 8

What are the two options for maceration before crushed fruit fermentation?

Answer 8

• Cold soaking

- macerations using heat

Question 9

Describe cold soaking AKA pre-fermentation maceration

Answer 9

• Juice and skins chilled to 39-50F to reduce spoilage, oxidation, risk of spontaneous fermentation.
• 3-7 days, usually with punching down/pump over to mix skins and juice to aid extraction and to avoid acetic acid bacteria build up.
• cold temps = slow extraction
• Common on pinot noir to promote color intensity. PN has low levels of anthocyanins
• Takes time, uses tank space so suited for low-volume wine.

Question 10

What are the two methods of macerations using heat

Answer 10

• Flash Detente

- thermovinification

Question 11

Macerations at higher temps give what?

Answer 11

greater extraction

Question 12

Describe Flash Detente

Answer 12

• Destemmed grapes heated to around 185-194F then rapidly cooled under a vacuum. Takes about 2 mins.
• Very rapid extraction
• Risk of cooked flavors
• Usually only used in high volume winery
• Used as a treatment for smoke taint

Question 13

Describe thermovinification

Answer 13

• Heating must to around 122-140F for minutes to hours

- Higher the temperature, the shorter the maceration time

Question 14

Besides heat, what do Flash Detente and Thermovinification have in common?

Answer 14

• Juice may be pressed off skins before fermentation if a low tannin, fruity style is desired. However, this leads to color instability bc not enough tannin to bind with anthocyanin
• Can be beneficial if grapes are affected by grey rot.

Question 15

Name the 5 cap management techniques

Answer 15

• Punch down
• Pump over
• rack and return
• Ganimede tanks
• Rotary fermenters

Question 16

Why is cap management important?

Answer 16

• It is important to mix the skins with the juice or wine during fermentation. Otherwise the skins would only macerate in the small volume of liquid surrounding them.
• Dry caps allows bacteria to convert alcohol into acetic acid
• helps aerate the must
• helps distribute heat
• influences wine style with tannin extraction, color extraction, avoids reductive sulfur compounds.

Question 17

How does the timing of mixing within fermentation influence what compounds are extracted?

Answer 17

more mixing at the start of fermentation with less mixing at the end will extract more color and less tannin, whereas mixing more at the end of fermentation will extract a greater amount of tannin.

Question 18

Describe the process of punching down

Answer 18

a plunger is used to submerge the cap of skins in the liquid

• either mechanized or by hand
• labor intensive by hand, so best suited to low-volume premium wines.
• carried out in small, open-top vessels
• gentle process

Question 19

Describe the process of pumping over

Answer 19

• juice/wine is taken from near the bottom of the vessel and sprayed over the cap of skins.
• usually around 1/3 to 1/2 of the liquid is sprayed
• extraction is gentle and usually punching down or rack and return is required to extract enough color, flavor ad tannin
• Can be programmed

Question 20

How can pumping over becomes an aerobic process?

Answer 20

-Splashing the juice/wine against the inside wall of the open vat which exposes the must to oxygen. This is beneficial for yeast health and avoiding off-flavors

Question 21

How can pumping over become an anaerobic process?

Answer 21

inside closed vessels with a hose attached to a tap at the top of the vessel or by keeping the hose close to the cap in an open vessel.

Question 22

Describe rack and return

Answer 22

• similar to pumping over
• juice pumped from one vessel into another and back into original
• more extractive than pumping over, use maybe 1-3 times
• often used along side pumping over
• most commonly used for extracting high levels of flavor, color, tannin (cab, syrah)
• cannot fully automate.

Question 23

What is a Ganimede tank and how is it used?

Answer 23

• Specialized tanks that bubble CO2 up through must/wine
• Pressure builds, cap bursts, quickly breaks apart the cap
• very extractive
• oxygen can be used instead of CO2 if desired.

Question 24

Describe rotary fermenters

Answer 24

• cap is mixed in a rotating tank
• very effective, highly programmable
• usually for high-volume
• expensive
• not as precise

Question 25

In addition to cap management, what other two techniques can be used?

Answer 25

- must concentration (via Sagniee) | - Co-fermentation

Question 26

What are the 3 types of whole berry/bunch fermentations?

Answer 26

- Carbonic maceration - Semi-carbonic maceration - Whole berry/bunches with crushed fruit

Question 27

What are important considerations if a winemaker intends to use whole bunches?

Answer 27

- -grapes must be hand harvested. - stems must be fully ripe otherwise they can add unpleasant green flavors and bitter tannin - ripe stems can add spicy and/or herbal aromas and tannin - Stems can also be added to crushed fruit fermentations to provide some tannins and spice

Question 28

What is the objective of whole berry/bunch fermentations?

Answer 28

-To create an oxygen-free environment for the uncrushed fruit

Question 29

What are the outcomes of the lack of oxygen with whole berry/bunch fermentation?

Answer 29

- Grapes change from aerobic respiration to anaerobic metabolism. In the anaerobic process, some sugar in the grape is converted to alcohol - this occurs without involvement of yeast and is called "intracellular fermentation." - Malic acid is broken down to create ethanol which reduced magic acid levels by up to 50% - Glycerol levels increase which add texture and a range of distinctive aromas - kirsch, bubblegum, etc

Question 30

Describe the process of carbonic maceration

Answer 30

- Uncrushed berries are placed into vats which are filled with CO2 to remove oxygen. - Grapes are either crushed by their own weight or manually. Fermentation begins. - Grapes are pressed - Press juice and free run are usually blended - Yeast completes fermentation off the skins - Extract color, but very little tannin - Resulting wines are fruity, low tannin, distinct but not necessarily complex

Question 31

Describe Semi-Carbonic maceration

Answer 31

- Similar to carbonic maceration, but here, the CO2 produced by fermentation fills the tank. - Ambient yeast starts fermentation, cultured yeast may be added - Grapes pressed, yeast completes fermentation off the skins - Produces a wine with slightly more concentration, body, tannin, and longer aging potential - Alcoholic fermentation continues and may involve punching down/pump over - Alc fermentation may be followed up by post-fermentation maceration or maturation in oak for complexity - This approach can lead to better integration of aromas from intracellular fermentation, more fruitiness, softer mouthfeel than crushed fruit fermentations - EX: Pinot noir, gamay, tempranillo

Question 32

Describe mixing whole berries/bunches with crushed fruit

Answer 32

- A further variation is to mix whole berries/bunches at the start of fermentation - stems must be ripe if using whole bunches - More "carbonic" characteristics can be achieved by increasing proportion of whole berries/bunches - cap is regularly punched down - similar to semi-carbonic, a period of post fermentation maceration and/or oak maturation may follow

Question 33

Describe the effects of fermentation temps and vessels for red wines

Answer 33

- high temps = high extraction, but high temps can evaporate volatile fruity aromas - Fruity, low-tannin wines = cool temps - higher concentration = warm temps - temp can be monitored throughout fermentation to control extraction and promote health fermentation to dryness - stainless steel, concrete, large wooden vessels can be used. - Vessels can be open or closed - Oak is thought to give a rounder mouthfeel and better integration of oak compounds during maturation - Stainless and concrete help retain fruit flavors

Question 34

Describe post-fermentation maceration

Answer 34

- Thought to further extract tannins and encourage polymerization of tannins with the aim of improving tannin structure, texture, wine's aging potential - Generally for premium and super-premium wines intended for aging

Question 35

When does pressing take place?

Answer 35

-when no more extraction is desired.

Question 36

What happens during pressing?

Answer 36

- press wine may be blended with free run as a blending component to add color, flavor, tannin - the quality of the fruit management and of the press are important considerations with high quality grapes and the gentle first pressings' ability to enhance tannin structure of a wine

Question 37

How does the wine style determine the timing of pressing?

Answer 37

- carbonic maceration styles, pressingly occur when the fermenting must reaches 2% abv to produce a wine with medium levels of color but low levels of tannin - After post-fermentation maceration to maximize tannin structure - straight after alcoholic fermentation or just before the end. Thought to lead to a better integration of oak flavors and rounder mouthfeel

Question 38

Describe MLC for red wines

Answer 38

- routine for red wines - vessel in which is happens may vary - conversion in oak may lead to better integration of oak characteristics during maturation - winemaker can decide if it takes place during or after fermentation - Winemaker may adjust acidity at this stage

Question 39

Inexpensive red wines usually get what as oak treatment?

Answer 39

staves or chips

Question 40

Oak maturation in red wines is a gentle form of what?

Answer 40

oxidation

Question 41

What does gentle oxidation of red wines during maturation lead to?

Answer 41

development of tertiary aromas and flavors, softening of tannins

Question 42

Why might new oak be used for red wine maturation?

Answer 42

if the winemaker feels the flavor of oak (vanilla, clove, etc) would enhance the complexity

Question 43

Why might a winemaker choose not to mature in oak o use a minimal amount of aging in old oak?

Answer 43

winemaker wants focus to be on primary aromas and flavors

Question 44

What can lees aging do for red wines?

Answer 44

- can help soften tannins - can possibly reduce color intensity - not typical to stir lees when making red wines

Question 45

What processes are usually combined with pumping over?

Answer 45

- Rack and return | - punching down

Question 46

What processes are usually combined with cold soaking? Why?

Answer 46

Punching down and pumping over To mix skins with juice and to aid extraction and avoid acetic acid bacteria from building up

Question 47

What two fermentation choices does a winemaker have after grape reception?

Answer 47

Crushed fruit fermentation | Whole bunch/berry fermentation

Question 48

How are the vast majority of red wines made?

Answer 48

By destemming and crushing the fruit before fermentation.

Question 49

In crushed fruit fermentations, when may pre-fermentation must adjustments be made?

Answer 49

adjustments can be made to the acidity, sugar, and tannin levels as needed.