9. Harvest

Question 1

By what 3 metrics is ripeness measured?

Answer 1

• sugar levels
• acidity levels
• aroma and tannin ripeness

Question 2

how are sugar levels in grapes measured?

Answer 2

-handheld refractometer. most dry still wines are harvested between 19-25 Brix, which will convert into 11-15% alcohol.

Question 3

how are acidicy levels measured in grapes?

Answer 3

Titration can be sued to calculate acid levels.

-also pH of the juice read by a pH meter

Question 4

what determines aroma and tannin ripeness

Answer 4

usually determined by taste (with experience)

Question 5

How does wine style influence date of harvest?

Answer 5

Example: in the case of Loire Valley Chenin Blanc, growers harvest grapes over 4-6 weeks, according to the style of wine. Early for sparkling, mid-harvest for dry and off-dry styles, late for botrytis or late-harvest styles.

Question 6

Advantages of machine harvesting?

Answer 6

• faster and cheaper than hand harvesting, especially in large vineyards if vineyard was designed with machine harvesting in mind.
• avoids issue of lack of labor and unreliable labor
• grapes can be harvested at night therefore kept cooler, reducing microbial spoilage and oxidation
• timing of harvest can wait until desired level of ripeness has been achieved, then carried out quickly.

Question 7

Disadvantages of machine harvesting?

Answer 7

• less gentle than hand harvesting. potential of damaged grapes
• rental/ownership of machine sometimes unreasonable for small vineyards
• not suitable for steep slopes
• quality of work only as good as the operator.
• may be competition for machine at best moment for harvest
• major investment to purchase

Question 8

Advantages of hand harvesting?

Answer 8

• pickers can be highly selective on a bunch by bunch level, can removed diseased, over/under ripe bunches
• pickers ca deal with steep slopes, irregular rows, mixed plantings in the same vineyard
• accidental crushing of grapes in crates can be avoided.

Question 9

Disadvantages of hand harvesting?

Answer 9

• more expensive than machine harvesting in medium-large vineyards
• requires availability of a reliable work force, their training, supervision to ensure required standard of work and quality.
• harvest most easily carried out in daylight hours and may not be able to avoid high temps which raises chance of grapes being spoiled by microbes or oxidation

Question 10

Why would hand harvesting be required?

Answer 10

• if whole bunches are required: champagne, beaujolais
• wine stye requires selective harvesting: botrytis
• steep slopes
• bush vines