Chapter 9 - Harvest

Question 1

What is the general rule of thumb on when to harvest?

Answer 1

100 days after flowering

Question 2

Traditionally in European regions, readiness for harvest was measured by:

Answer 2

Potential alcohol level

Question 3

Recently, what factors have changed decisions on harvesting dates?

Answer 3

1. A generally warmer climate so it’s easier to ripen grapes in cool climates
2. Better viticulture so the grapes ripen fully
3. Focus on aroma and tannin ripeness over sugar ripeness

Question 4

What is the general amount of sugar desired during harvest? How is it measured?

Answer 4

Handheld refractometer

Between 19 and 25deg Brix - converts to 11-15% abv

Question 5

How do you measure acidity levels in grapes?

Answer 5

Tritration - adding another substance to know the amount of a substance in a solution
Using pH meter to read pH of juice

Question 6

How do you measure aroma and tannin ripeness?

Answer 6

By taste

Question 7

Ways to improve machine harvesting

Answer 7

1. Selectung out undesirable fruit by hand before machine harvesting
2. Use a bow-rod shaking machine - gentler and more specific
3. Machines w/ Optical sorting devices and can crush white grapes and add SO2 in the machine automatically
4. Rigorous sorting on arrival includng removal of MOG and unripe/rotten grapes

Question 8

Pros of Machine Harvesting

Answer 8

Significantly faster and cheaper in large vyds if vyds were designed for machine harvesting

Don’t have to be concerned about lack of workers

Grapes can be harvested at night and kept up to 15C cooler than if picked during the day

Timing of harvest can wait until the desired level of ripness has been achieved and then carried out quickly

Question 9

Cons of Machine Harvesting

Answer 9

• Less gentle than hand harvesting
• rental or ownership of machine is not cost effective for small vyds
• Unsuitable if several different varieties ripen at differnet times in the same plot
• not suitable for slopes
• quality is only as good as the operator
• competition for rental of the machine
• purchasing a machine is a major investment
• not possible for whole cluster harvest

Question 10

Pros of Hand Harvesting

Answer 10

• highly selective to remove diseased/under/extra ripe fruit
• steep slopes, irregular rows, mixed plantings okay
• prevents crushing of grapes when small crates are used

Question 11

Cons of Hand Harvesting

Answer 11

• more expensive than machine harvesting in med - large vyds
• requires skilled workers
• harder to do at night

Question 12

What wines require hand harvesting?

Answer 12

• whole bunches (like for premium sparkling)
• carbonic/semi-carbonic maceration
• when many rounds of picking is required - botrytis-affected bunches, late ripening grapes
• steep slopes
• uneven land
• bush vines