Chapter 18 - Red Winemaking

Question 1

What are the 3 main components winemakers are most focused on extracting in red winemaking?

Answer 1

Tannin
Anthocyanins
Flavors from skins

Question 2

3 factors that affect extraction:

Answer 2

1. Temperature - the higher the temp, the greater the extraction
2. Length of time on skins - the longer time the skin is in contact with the juice (and evenly spread out throughout the juice), the greater the extraction
3. The medium in which extraction takes place - anthocyanins are more soluble in water solutions, tannins are more soluble in alcoholic solutions

Question 3

Describe the relationship between anthocyanins, tannins, and oxygen

Answer 3

Anthocyanins provide the color of the wine. However, it is unstable by itself and can easily be lost during lees aging, and by SO2. Tannins can stabilize color by binding to anthocyanins and oxygen aids this process (hence why oxygenation is promoted in red wine fermentation and aging)

Question 4

What is a con to producing low tannin, fruity reds with macerations using heat? What else can you do with this juice?

Answer 4

If the juice is pressed off the skins before fermentation because a low tannin, fruity style is desired, color instability becomes a common problem because not enough tannins were extracted

Therefore this is only used to make cheap to mid-priced wines meant to be consumed shortly after production

You can also blend this juice into higher quality wine and bring juicy, fruity flavors to the blend

Question 5

What is the key aim of maceration before fermenation? What are the 2 methods?

Answer 5

Extract color and flavors without extracting tannins

cold soak
Maceration using heat (flash détente and thermovinification)

Question 6

Describe the process of cold soaking

Answer 6

Crush the berries
Juice and skins are chilled to 4-10C (reduces oxidation, spontaneous ferm, and microbial spoilage)
Lasts 3-7 days
Usually uses punching down and pumpking over to mix up the skins and juice to aid extraction - this also prevents growth of spoilage organisms that need O2 like acetic acid bacteria on the caps
Gentle technique suitable for premium wines
Slow extraction that can be monitored and controlled
Costly - energy required to chill the wine, taking up valuable tank space for a period of time

Question 7

Whats the main difference between cold soak and maceration with heat?

Answer 7

`maceration using heat extracts high levels of anthocyanins and flavors quick;y

Question 8

Describe flash détente

Answer 8

Destem the grapes (don’t crush)
Quickly heat to 85-90C for a couple minutes and then rapidly cool under a vacuum
This causes the skins to bust, allowing the rapid color and flavor extraction
Short time prevents ‘cooked’ flavors
Costly bc of vacuum system
Generally only used by high volume wineries

Question 9

Describe Thermovinification

Answer 9

Crush the berries

Heat the must to 50-60C for a number of minutes to several hours

Question 10

When would you prefer using maceration using heat?

Answer 10

If the grapes have been affected by botrytis (grey rot) bc the high temp denatures laccase (the enzyme produced by the rot that oxidizes wine components and is relatively unaffected by SO2)

Flash détente can be used to treat smoke taint

Question 11

Why do some critics not like maceration using heat?

Answer 11

Causes a reduction in more suble varietal characters

Question 12

Maceration during fermentation techniques:

Answer 12

1. Cap Management
2. Must Concentration
3. Co-fermentation

Question 13

What is the cap during fermentation?

Answer 13

The grape skins that rise to the top of the liquid and remain there bc of CO2

Question 14

Why is it important to mix the cap and juice?

Answer 14

1. Without mixing, the skins macerate only in teh same small volume of liquid they’re in contact with. This liquid becomes saturated with color, flavor, and tannins and no longer extracts more
2. A dry cap allows bacteria to convert alcohol into unwanted acetic acid (O2 exposure)
3. Avoids over production of reductive sulfur compounds
4. Helps distribute the heat produced during fermentation

Question 15

What aspects of cap managment impact the style of wine made?

Answer 15

1. The cap management technique used
2. The frequency of mixing and duration of mixing
3. The timing of the mixing influences the compounds extracted

Question 16

During cap management, how does the timing of the mixing incluence what compounds are extracted?

Answer 16

More mixing at the start of fermentation with less in the end will extract more color and less tannin
Vice versa

Question 17

Cap Management Techniques:

Answer 17

1. Punching Down
2. Pumping over
3. Rack and return
4. Ganimede tanks
5. Rotary fermenters

Question 18

French term for Punching Down

Answer 18

Pigeage

Question 19

Describe Punching Down

Answer 19

A plunger submerges the cap by hand or mechanized
Doing it by hand is labor intense and taxing and therefore ony suited to low volume, premium wines
Small open top vessels must be used (only way to physically punch down teh cap and ensure adequate mixing)
Gentle process
Used on several grape varieties

Question 20

Describe Pumping Over

Answer 20

Juice is taken from near the bottom of the vessel and sprayed over the cap
As the juice passes through the cap, it extracts color, flavor, and tannins
Very gentle and generally must be paired with punching down or rack and return for enough extraction
Can be done aerobically and anaerobically
Commonly used on all varietals
For wines of all price points and qualities
Suitable for large vessels
Can be mechanized - can be pre-programmed to occur at a certain time for a certain duration

Question 21

French term for Pumping Over

Answer 21

Remontage

Question 22

Describe Rack and Return

Answer 22

Similar to pumping over but the juice is pumped into another tank and then returned
As the juice is pumped back into the tank, it is sprayed over the cap, breaking it up and mixing the juice and skins thoroughly
More extractive than pumping over or punching down - therefore can only be used 1-3 times during fermentation
Used for reds with medium to high levels of falvor, color, and tannin desired (cab, syrah)
Cannot be fully automated
Requires another clean vessel to be available

Question 23

French term for rack and return

Answer 23

Delestage

Question 24

Describe Ganimede Tanks

Answer 24

Specialized takms that bubble CO2 up through the must, causing pressure build up under the cap and bursting the cap
Relatively extractive like Rack and return
Used for wines with medium to high tannin, color, flavor extraction (cab, syrah)
Can be fully automated
Tanks are expensive
O2 can be used instead of CO2

Question 25

Describe Rotary Fermenters

Answer 25

Horizontal, closed, SS tanks where the tank rotates and has internal blades that break up the cap Horizontal position increases the surface area of skins that touches juice High level of extraction Used for med to high level color, flavor, tannin extraction wines (cab, syrah) Highly mechanized - can be programmed to rotate at certain times for a certain amount of time Commonly used for high-volume, inexpensive, or mid-priced wines with ok quality Costly

Question 26

What are the gentle cap management techniques?

Answer 26

Punch Down | Pumping Over

Question 27

What are the extractive cap management techniques?

Answer 27

Rack and return Ganimede tanks Rotary Fermenters

Question 28

Describe must concentration

Answer 28

increasing color, flavor, and tannins by drawing off the juice thats lighter in color, flavor, and tannin This concentrates the remaining must but decreases overal volume (price implications) Drawn off juice usually used to make rosé (saignée method)

Question 29

Describe co-fermentation

Answer 29

Fermenting usually a small percentage (up to 5%) of white grapes to take advantage of some of the phenolic ocmpoudns found in white grape varietals that can increase color intensity adn stability through binding with anthocyanins Popular in Cote Rotie (Syrah and Viognier) No cost incurred

Question 30

3 types of whole berry/bunch fermentation

Answer 30

1. Carbonic maceraiton 2. Semi carbonic maceration 3. Whole berries/bunch with crushed fruit

Question 31

Whats important about the stems in whole bunch fermentation? What varietals do you usually not use it for?

Answer 31

Must be ripe Contribute spicy, herbal flavors and tannins Unripe stems give green flavors and bitterness Varietals naturally high in tannins (ie cab)

Question 32

What is the objective and what happens during whole berry/bunch fermentation?

Answer 32

Create an oxygen free environment for the uncrushed fruit Grapes change from aerobic respiration to anaerobic metabolism, casuing some of the sugar to convert to alcohol without yeast (intracellular fermentation) Malic acid also breaks down to create ethanol (up to 50%) (increases pH) Glycerol levels rise - adds texture and aromas (kirsch, banana, bubble gum, cinnamon)

Question 33

Describe Carbonic Maceration process

Answer 33

Placing whole, uncrushed bunches into a vessel filled with CO2 Intracellular fermentation starts and produces ~2% alcohol by volume Grapes are then crushed normally or the grape skins start to split and juice is released Normal fermentation commences Juice is drained and grapes pressed - blended Fermentation via yeast completes the process

Question 34

What is the style of wine that results from carbonic maceration?

Answer 34

High color extraction Low tannin extraction Distinctive notes from intracellular fermentation & fruity varietal notes Oak gnerally not used

Question 35

Describe intracellular fermentation

Answer 35

Alcohol conversion without yeast | Grapes change from aerobic respiration to anaerobic metabolism, causing the sugar in the grapes to convert to alcohol

Question 36

Describe the Semi-Carbonic Maceration process

Answer 36

Vessel is not filled with CO2 Whole bunches added in Bottom grapes are crushed by the weight of the grapes and some juice is released yeast starts to ferment that juice, producing CO2 that fills the vessel and the remaining intact grapes undergo carbonic maceration When teh intact grapes begin to split and release their juice, the grapes are pressed and the yeast complete the fermentation on or off the skins Post fermentation maceration and maturation in oak optional to add complexity This can help better integraiton of aromas from intracellular fermentation with aromas from teh grape variety Result: wines with more fruitiness and a softer mouthfeel than crushed fruit fermentation Used to make fruity style wines of all varieties

Question 37

Describe Whole Berries/bunches with crushed fruit

Answer 37

Mix whoel berries/bunches with crushed fruit in the fermenting vessel at the start of fermentation Intracelluluar fermentaiton happens bc the whole bunches are submerged in the crushed grape juice More carbonic characteriestics can be achieved by increaseing hte amount of whole berries/bunches used Whoel berries progressively crushed as cap is regularly pumched down Post-fermentation maceration and oak optional Gives smoother texture and more vibrant and fresh primary aromas than crushed fruit fermentation Used on a wide variety of grapes

Question 38

What kind of oak is generally used for red winemkaing and in what orientation?

Answer 38

Generally large vats Barrels are kept on their sides with one of hte heads removed to form a very small open top fermenter

Question 39

Why do winemakers ferment in oak?

Answer 39

Gives a rounder mouthfeel and leads to better integration fo oak compounds during maturation

Question 40

Why do winemakers ferment in cement and SS?

Answer 40

Retain fruit flavors

Question 41

How long can post-fermentation maceration last?

Answer 41

A few days to a few weeks

Question 42

Why do post-fermentation maceration?

Answer 42

Further extract tannins and encourage the polymerisation of tannins This improves tannin structure nad texture and the wine's aging potential

Question 43

Why have MLF occur in oak?

Answer 43

Better integration of oak characteristics during maturation

Question 44

Whats the typical amount of time mid - premium wines mature in barrel?

Answer 44

6months - 2 years

Question 45

Why mature in barrel?

Answer 45

Soffen tannins | Develop tertiary aromas and flavors for complexity and quality

Question 46

Pros and cons of aging red wines on lees?

Answer 46

Pro: soften tannins Con: loses color intensity *Not typical to leave gross lees or stir the lees in reds