18.3 Whole Berry/Bunch Fermentations

Question 1

If whole bunches are used in fermentation, how must the grapes have been harvested?

Answer 1

Hand-harvested

Question 2

What are the two options for using uncrushed fruit in fermentation?

Answer 2

1. whole bunches of grapes

2. whole destemmed grapes

Question 3

If using whole bunches of grapes are used, what is very important? Why?

Answer 3

• stems of the bunches must be fully ripe

- unripe stems can add unpleasant green flavours and bitter tannins

Question 4

What desirable flavours can stems add?

Answer 4

• ‘spicy’ or ‘herbal’

- can also add some tannins

Question 5

What might producers do to crushed fruit fermentations to add ‘spicy’ or ‘herbal’ flavours?

Answer 5

add left over stems from the destemming process

Question 6

Why might a producer specifically choose not to add stems?

Answer 6

• when fermenting grape varieties with naturally high tannins
• e.g. Cabernet Sauvignon

Question 7

What is the objective of whole berry/bunch fermentation?

Answer 7

• to create an oxygen free environment for the uncrushed fruit

Question 8

What are the outcomes of an oxygen-free fermentation of whole berries/bunches?

Answer 8

• grapes change from aerobic respiration to anaerobic metabolism
• some sugar is converted to alcohol (without yeast)
• malic acid broken down to create ethanol (reducing malic acid by 50%, lowering acidity, raising pH)
• glycerol levels increase (add texture)
• distinctive aromas created inside the grape (kirsch, banana, bubble gum and cinnamon)

Question 9

What is intracellular fermentation?

Answer 9

• grapes change from aerobic respiration to anaerobic metabolism
• some sugar is converted to alcohol without the involvement of any yeast

Question 10

What flavors are the result of whole berry/bunch fermentation?

Answer 10

kirsch, banana, bubble gum, cinnamon

Question 11

What are the costs associated with whole berry/bunch fermentation?

Answer 11

• techniques do not have a significant impact on cost

- hand-harvesting, sorting, use of oak will all add costs

Question 12

What are the 3 forms of whole berry/bunch fermentation?

Answer 12

1. Carbonic Maceration
2. Semi-Carbonic Maceration
3. Whole Berries/Bunches w/ Crushed Fruit

Question 13

What is carbonic maceration?

Answer 13

• only whole, uncrushed bunches used
• vessels filled with CO2 to remove all oxygen
• intracellular fermentation starts
• alcohol level in grape reaches ~2%
• grapes skins split, juice released
• juice drained
• grapes pressed
• free run juice + press juiced blended
• fermentation completes

Question 14

When do the grape skins start to split in carbonic maceration?

Answer 14

When the alcohol level in grape reached ~2%

Question 15

What does carbonic maceration extract from the grapes? What does it barely extract?

Answer 15

• Extracts colour

- Barely extracts any tannins

Question 16

Describe a wine that has gone through carbonic maceration.

Answer 16

• fruity
• low tannins
• not super complex
• distinctive notes of kirsch, banana, bubble gum and cinnamon-like spice
• fruit notes from the grape variety
• unlikely to use oak

Question 17

When are wines that go through carbonic maceration best consumed?

Answer 17

within a year after harvest

Question 18

What quality wines are typically made with carbonic maceration?

Answer 18

acceptable or good, inexpensive and mid-priced wine

Question 19

Name a region and a type of wine that are famous for carbonic maceration.

Answer 19

• Beaujolais

- Beaujolais Nouveau

Question 20

What is semi-carbonic maceration? How is it different from carbonic maceration?

Answer 20

• does not involve filling the vessel with CO2
• start with whole bunches
• bottom grapes crushed under the weight of the grapes above
• some juice released
• ambient yeast start to ferment the juice (cultured yeast can also be added)
• fermentation produces CO2, which fills the vessel
• remaining intact grapes undergo carbonic maceration
• intact grapes begin to split
• release their juice
• grapes are pressed
• yeast complete the fermentation off skins

Question 21

How might a producer use semi-carbonic maceration but also create a wine with slightly more concentration, body and tannin, and hence a longer ageing capacity?

Answer 21

• Continue the alcoholic fermentation on the skins
• Punching down or pumping over
• Ever-decreasing amount of carbonic maceration takes place
• Post-fermentation maceration and/or maturation in oak

Question 22

When fermentation is continued on the skins post semi-carbonic maceration, what does it add to the wine?

Answer 22

• better integration of the aromas from intracellular fermentation with aromas from the grape variety
• more fruitiness
• softer mouthfeel

Question 23

How is whole berry/bunch with crushed fruit fermentation carried out?

Answer 23

• not blanketed in CO2
• whole berries/bunches largely submerged by crushed grapes
• kept away from oxygen
• intracellular fermentation takes place
• berries crushed
• cap regularly punched down

Question 24

What are the effects of whole berry/bunch with crushed fruit fermentation on the end wines?

Answer 24

• smoother texture

- more vibrant and fresh primary aromas (than crushed fruit fermentations)

Question 25

What styles and qualities of wines is whole berry/bunch with crushed fruit fermentation used on?

Answer 25

• wide range of grape varieties

- wines of different qualities and prices