9. Harvest

Question 1

What are the 2 main factors that determine “grape ripeness?”

Answer 1

1) Sugar levels
2) Aroma / Tannin Ripeness

Question 2

What are the advantages of hand harvesting? (3)

Answer 2

1) pickers can be highly selective (removing diseased, underripe, extra-ripe fruit),
2) pickers can deal with higher slopes and mixed plantings
3) if grapes are put in stackable crates – it avoids crushing of grapes

Question 3

What is the name of the tool used for hand-harvesting grapes?

Answer 3

Secateur

Question 4

What are advantages of machine harvesting? (5)

Answer 4

1) significantly faster and cheaper in large vineyards
2) don’t need as many trained laborers
3) grapes can be harvested at night (cooler) = reduction of microbial spoilage + oxidation.
4) timing can wait until desired level of ripeness and then harvested quickly
5) Cooler fruit = preservation of fruit aromas (esp. in white grapes)

Question 5

What steps can be taken to improve the quality of machine harvested grapes? (4)

Answer 5

1) select out undesirable fruits by hand before harvest
2) use bow-rod shaking machine (gentler version than traditional shakers)
3) newest machines have optical sorting devices, can crush white grapes +add SO2
4) rigorous sorting upon arrival at winery

Question 6

Despite all the technologically advanced methods of determening grape ripeness, what simple method remains one of the most important ways of deciding when to harvest?

Answer 6

Tasting the grapes.

Question 7

What choice do grape growers face if there is a threat of rain near harvest?

What are the possible negative effects of rain in the last days before harvest (4)?

Answer 7

Choice btw/ harvesting under-ripe fruit or leaving grapes on vine hoping weather will improve.

• diluting of juice
• splitting of skins due to rapid expansion
• threat of grey rot
• all of which lead to loss of some/all of harvest.

Question 8

In recent times, how has the context for making decisions about when to harvest changed? (3)

Answer 8

1) a generally warmer climate = easier to ripen grapes incool regions
2) better viticulture – allowing grapes to ripen fully
3) focus on aroma/tannin ripeness vs. optimum sugar ripeness

Question 9

What are disadvantages of machine harvesting? (7)

Answer 9

1) less gentle, doesn’t keep bunches intact = can’t be used for whole cluster, ice wine, botrytised wine etc…
2) not economic/practical for small scale vineyards
3) unsuitable for growers that have different varieties ripening at different times on same plot
4) can’t be done on slopes
5) quality of work is only as good as skills of operator.
6) may be competition for availability of harvesters in regions with less of them.
7) Purchasing harvester = major investment

Question 10

What tool is used to measure sugar levels in ripening grapes?

What is a normal measurement for harvested grapes?

What abv will this most likely convert to in a finished wine?

Answer 10

Handheld refractometer.

For most dry, still wines, grapes are harvested btw/ 19^o - 25^o Brix.

This will convert to 11-15% abv.

Question 11

Identify 4 pieces of technology which can be used to measure grape ripeness in the vineyard:

What do they measure?

Answer 11

1) Handheld Refractometer (measures Brix / level of sugar in juice)
2) Titration (calculates acid levels)
3) pH Meter (acidity)
4) Visible / Near infrared spectroscopy (gives readings for sugar, acidity and other components of grapes.)

Question 12

How has readiness for harvest traditionally been measured in European regions?

Give examples of how this (legally) differs in different regions(3):

Answer 12

Potential Alcohol Levels

e.g. AOC regulations require the following min. PALs:

Petit Chablis: 9.5%

Chablis: 10%

Bougogne Blanc: 10.5%

Question 13

What are some examples of when hand harvesting is required? (4)

Answer 13

1) for premium sparkling wines (whole bunches are required, e.g. Champagne)
2) Beaujolais (carbonic maceration requires whole bunches)
3) styles that require only Botrytis-Affected grapes e.g. Tokaji
4) on steep slopes, uneven land and bush vines e.g. Douro Valley

Question 14

What are the 2 main points of view regarding extended “hang time” for grapes?

Answer 14

1: Some critics believe this practice leas to overly alcoholic/unbalanced wines that lack acidity.

Question 15

What are the disadvantages of hand harvesting? (3)

Answer 15

1) more expensive in med.-large vineyards
2) requires availability of reliable work source
3) must be done during daylight hours in temperatures that aren’t too high

Question 16

3 specific examples of how harvest dates change depending on the specific style of wine desired:

Answer 16

1) Loire Valley Chenin Blanc; grapes harvested over 4-6 weeks (early = sparkling / mid = dry+off dry / late = botrytis or late harvest styles)
2) California Zinfandel; White Zin = mid-August harvest / Red = September. Since Zinfandel is prone to uneven ripening, grapegrowers will closely monitor grapes to determine harvest time.
3) Wines with RS; Botrytized grapes = hand-harvested late in the season. Eiswein / Icewine = grapes picked when temps dip below certain levels (-8C / 18F)

Question 17

What is an exception to the trend that grapes for most high-volume, inexpensive wines are machine-harvested?

Answer 17

S. Africa, where there is plenty of availability of labor at a low cost.