13.3 General Winemaking Options: Grape Reception

Question 1

What factors are at play when it comes to reception of the grapes at the winery?

Answer 1

• the volume of the grapes
• whether they have been hand- or machine-harvested
• the health and quality of the grapes

Question 2

If large volumes of grapes need to be moved on reception, how is that typically done? Which option is gentler?

Answer 2

• conveyor belt (gentler with higher quality potential)

- a screw conveyor

Question 3

If small volumes of hand-harvest grapes need to be moved, how is that typically done?

Answer 3

• manually, often with a pallet truck or forklift

Question 4

To what phase(s) do conveyer belts and screw conveyers take grapes?

Answer 4

• sorting

- destemmer/crusher

Question 5

Why might a winemaker choose to chill the grapes on reception?

Answer 5

• If the grapes are warm when they reach the winery (e.g. they have been picked on a sunny, warm afternoon)
• decreases rate of oxidation
• preserves fruity aromas
• reduces microbial spoilage

Question 6

How might whole bunches of grapes be chilled? Which option is quicker?

Answer 6

• a refrigeration unit (slower)
• a heat exchanger (if the grapes are in a more fluid format (e.g. fruit that has been machine picked, grapes that are destemmed and possibly crushed) (quicker)

Question 7

Why might a producer choose not to cool the grapes?

Answer 7

• costy

- slows the process of the grapes

Question 8

What is the French word for grape sorting?

Answer 8

Triage

Question 9

What 4 factors is the level of grape sorting dependent on?

Answer 9

1. ripeness and health of the fruit arriving at the winery
2. the intended final wine quality and price
3. whether any sorting has been carried out in the vineyard (e.g. by skilled hand-pickers)
4. the physical state of the grapes (if grapes arrive in large containers, the bottom grapes will have crushed and released juice; this is too liquid to sort)

Question 10

Why is sorting costly?

Answer 10

• labour requirement
• time taken for meticulous hand sorting
• greater scrutiny often results in less yield

Question 11

In poor years and in cool climates, how much sorting is required?

Answer 11

A greater of level of sorting may simply be required (for all but the most basic quality wines) to remove mouldy and under-ripe grapes.

Question 12

In very good years, how much sorting is required?

Answer 12

Very little, fruit may arrive in near perfect condition and require little sorting (just MOG)

Question 13

What is MOG?

Answer 13

Material other than grapes

- Examples: leaves, twigs, insects, etc.

Question 14

Name 3 sorting options for quality wines.

Answer 14

1. Removing unwanted grapes/bunches before picking or during hand-harvesting
2. Sorting by hand on a table or a moving or vibrating belt (the latter also removes MOG); this can take place before or after destemming, or occasionally both before and after destemming
3. Optical sorting

Question 15

What is optical sorting? Where is this sorting option typical?

Answer 15

• High-tech, high-cost option
• Uses digital imaging and software technology to scan individual grapes
• A machine scans a 100-grape sample chosen by the grape grower as a reference
• The full load of grapes to be sorted are then passed through the machine and it rejects individual grapes that do not conform to the sample and any MOG
• This can be done either in a harvesting machine or at reception in the winery
• High value grapes

Example: Grand Cru Classé estates in Bordeaux

Question 16

What types of grapes need to be destemmed upon arrival at the winery?

Answer 16

• Hand-harvest grapes
• most whites
• many reds

Question 17

How do destemmers work?

Answer 17

A series of blades within a rotating drum that remove the grapes from the stems

Question 18

If the stems are left in contact with the wine, what can happen?

Answer 18

• Stems contain tannins
• Tannins can be extracted
• Unwanted in white wines, desired in some wines

Question 19

If stems are unripe and are left in contact with the wine, what can happen?

Answer 19

• Unwanted green flavors

- Bitter tannins

Question 20

Give 3 examples in which grapes are not destemmed purposefully.

Answer 20

1. red wine fermentations that use some whole bunches (e.g. with Pinot Noir in Burgundy or Sonoma)
2. carbonic maceration (e.g. with Gamay in Beaujolais)
3. whole bunch pressing for some white wines (e.g. common for high-quality sparkling wine).

Question 21

What is crushing?

Answer 21

The application of sufficient pressure to the grapes to break the skins and release the juice, making it available for fermentation

Question 22

When does crushing occur?

Answer 22

At the beginning of the winemaking process

Question 23

What is extremely important during crushing?

Answer 23

The pressure applied is gentle enough not to crush the seeds, which would add bitterness

Question 24

Traditionally, how was crushing done?

Answer 24

By the pressure of human feet

Question 25

When a crusher-destemmer machine is used, what does that mean for sorting?

Answer 25

Sorting can only be done at the level of whole bunches

Question 26

What is must?

Answer 26

• The mixture of grape juice, pulp, skins, seeds that comes from the crusher
• Typically refers to the substance that is being fermented

Question 27

In white wines, what is must?

Answer 27

May also refer to the grape juice that is fermented (pressing and clarification means pulp, skins and seeds have been removed)