Identify

Question 1

Identify the effects of excess water during early grape growth, ie: preverasion.

Answer 1

if water is too easily available into late spring and early summer, vegetative growth (the growth of shoots and leaves) is promoted and prolonged into the period of grape ripening. This acts as a competitive source for the vine’s sugars, which can delay and compromise ripening. It is therefore thought that mild water stress before véraison is beneficial as it inhibits further vegetative growth.

Question 2

Identify three factors that affect nutrient availability for the vine.

Answer 2

1. soil pH
2. soil texture
3. topography

Question 3

Identify three decisions that a vineyard manager could make to counteract the effect of rising temperatures in their vineyard due to climate change.

Answer 3

1. site selection
2. choice of planting material
3. efficacy of different vineyard management techniques

Question 4

Identify the aims of sustainable viticulture.

Answer 4

1. promote the natural ecosystems in the vineyard
2. maintain biodiversity
3. manage waste
4. minimise applications of chemicals and energy use
5. reduce the impact of viticulture on the wider environment

Question 5

Identify 5 factors that would determine the suitability of land for the planting of a new vineyard.

Answer 5

1. natural resources (location, layout, topography)
2. price of the land
3. suitability of mechanisation
4. irrigation
5. ease of access (vineyards and winery)

Question 6

Identify 5 techniques for improving the soil texture or structure before planting a new vineyard.

Answer 6

1. remove very large rocks at or near surface
2. subsoiling (process of breaking down a plough pan - an
   impervious layer of soil)
3. remove and burn old roots
4. apply farmyard manure, compost and fertilisers
5. adjust soil pH

Question 7

Identify 4 factors to consider when choosing species of rootstock planting material.

Answer 7

1. pests
2. water
3. soil pH
4. vigour

Question 8

Identify an appropriate choice of rootstock for a vineyard that is prone to root-knot nematodes.

Answer 8

Ramsey and Dog Ridge (both Vitis champini)

Question 9

Identify the possible disadvantages of cultivation.

Answer 9

1. Repeated cultivation can damage the soil’s structure and ecology due to the breakdown of organic matter and disruption of earthworms in their habitat.
2. It is costly as it requires both skilled labour and machinery.
3. Disturbing the soil buries seeds, thus encouraging the weeds to grow back.
4. It can increase vine vigour too much as there is no competition for water or nutrients (not necessarily a disadvantage in low vigour sites (poor soils and/or lack of water)).

Question 10

Identify the natural and artificial methods for improving vineyard drainage.

Answer 10

1. leaving natural vegetation to grow or planting specific crops to provide competition for water, leaving less available for the vine
2. Improving soil structure and removing any plough pans to better regulate water drainage
3. Drainage pipe installation before planting the vineyard

Question 11

Identify four of the goals pertaining to canopy management.

Answer 11

1. maximise the effectiveness of light interception
2. promote air circulation through the canopy to reduce incidence of disease
3. arrange the vine canopy to ease mechanisation and/or manual labour
4. reduce the shade within the canopy

Question 12

Identify 7 types of summer pruning.

Answer 12

disbudding
–
shoot removal
–
shoot positioning
–
pinching
–
shoot trimming
–
leaf removal
–
crop thinning/green harvesting

Question 13

Identify three ways that a vineyard can be managed to reduce the threat of frost.

Answer 13

1. site selection (choose hillsides, avoid frost pockets)
2. choose late-budding varieties (e.g. Riesling) and /or delay pruning
3. Vines trained high off the ground offer more protection, as the coldest air is near the ground.

Question 14

Identify the symptoms of phylloxera.

Answer 14

• Vines die of drought in patches that increase in size year by year
• Vine roots are covered with the insects surrounded by yellow eggs
• Swellings on older roots
• Pale green leaf galls on the under-surface of the leaves
• Slow, stunted shoot growth and leaf yellowing appears in around three years, the plant dies after around five years.

Question 15

Identify three management techniques for grape moths.

Answer 15

Biological controls include the use of:
– the bacterium Bacillus thuringiensis (which produces substances that are toxic to the moths)
– use of pheromone capsules to disrupt mating (‘sexual confusion’)
– natural predators (parasitic wasps, green lacewings, some spider species).

Question 16

Identify 4 techniques that vineyards can use to control grey rot.

Answer 16

1. Selecting grape varieties that have small grapes with thick skins and therefore high levels of resistance (e.g. Petit Verdot) and protecting the grapes against other pests (which could split the skin of the grape) are the most important options.
2. Keeping an open canopy and removing the leaves around bunches can also reduce the spread of grey rot.
3. Traditional sulfur and copper sprays are ineffective, but other fungicides can be used. They should be applied at key points in the season – when flowering is nearly complete, at the end of grape formation, at bunch closure (when the grapes in a bunch get large
   enough so that they touch each other) and véraison. However, fungicides quickly become ineffective if the fungus develops resistance.
4. Attention has therefore turned to using antagonistic bacteria; for example, Bacillus subtilis and other forms of biological control.

Question 17

Identity 4 management techniques for mitigating Esca.

Answer 17

1. sourcing disease-free stock,
2. trying new, less detrimental, pruning techniques,
3. not pruning in the rain,
4. removing prunings promptly from the vineyard and disinfecting pruning wounds.

Question 18

Identify the symptoms of grapevine yellows.

Answer 18

delayed budburst, a drooping posture because the new shoots fail to become woody, and the canopy turning yellow (in white varieties) and red (in black varieties). In some strains, the vine dies as the disease progresses, in others it can recover after an attack.

Question 19

Identify three ways that the quality of fruit can be improved when using a mechanical harvesting approach.

Answer 19

1. selecting out undesirable fruit by hand before harvesting by machine
2. using a bow-rod shaking machine (rather than the older machines, which beat vines to remove the fruit); this is gentler and can be set to be more selective
3. investing in the very latest machines that have options for optical sorting devices on them and which can crush white grapes and add SO2 in the machine itself to limit oxidation
4. rigorous sorting on arrival in the winery, including removal of MOG (matter other than grapes) and unripe and rotten grapes.

Question 20

Identify 4 situations that would require hand harvesting.

Answer 20

1. premium sparkling wines made where whole bunches are required for whole bunch pressing (Champagne and most bottlefermented sparkling wine around the world).
2. grapes for Beaujolais and other wines that will be made by carbonic or semi-carbonic maceration require whole bunches for the process
3. if making a style of wine that requires selective harvesting of certain
   grapes, harvesting must be done by hand. For example, pickers may be instructed to harvest only botrytis-affected bunches (e.g. for Trockenbeerenauslese Riesling in the Mosel)
4. where they are grown on steep slopes (e.g. in the Douro
   Valley) or uneven land. Bush vines are harvested by hand

Question 21

Identify 4 positive attributes of wines with a low pH.

Answer 21

A low pH
1. increases the microbiological stability of wine,
2. increases the effectiveness of SO2,
3. gives red wines a bright red colour
4. enhances a wine’s ability to age well.

Question 22

Identify the 4 sources of aromatics in a wine.

Answer 22

1. Aromas from the Grapes
2. Aromas created by Fermentation due to the Presence of Aroma Precursors in Grape Must
3. Aromas originating from Fermentation and its By-products
4. Aromas from Other Sources (e.g. vanillin, eucalyptol)

Question 23

Identify the 4 levels of still wine residual sugar classification in the EU.

Answer 23

• Dry/sec/trocken etc. – up to 4 g/L RS, or not exceeding 9 g/L provided that total acidity expressed as grams of tartaric acid per litre is not more than 2 g below RS content. For
  example, a wine with 9 g/L RS can be labelled ‘Sec’ if it has 7 g/L total acidity.
• Medium dry/demi-sec/halbtrocken etc. – more than 4 g/L and not more than 12 g/L RS, or up to 18 g/L provided that the total acidity expressed as grams of tartaric acid per litre is not more than 10 g below the RS content.
• Medium or medium sweet/moelleux/lieblich etc. – more than 12 g/L and not exceeding 45 g/L RS.
• Sweet/doux/süss etc. – at least 45 g/L RS.

Question 24

Identify at least 4 methods used to increase oxygen exposure to must and wines.

Answer 24

Oxygen exposure can be increased by:
*
use of cap management techniques in red wine fermentation that spray or splash the must or wine
*
use of small wooden barrels that can only contain a small volume of wine relative to the amount of oxygen that enters through the bung holes and staves
*
increasing the number of rackings or amount of lees stirring during ageing; any procedures that require the bung of a barrel or lid of a vessel to be removed and the wine to be moved will increase oxygen exposure
*
allowing ullage in wine containers without the use of inert gases in the headspace
*
use of techniques that involve pumping oxygen through the must (e.g. hyperoxidation) or wine (e.g. micro-oxygenation)

Question 25

Identify the two preservative qualities of sulfur dioxide.

Question 26

List 5 ways to reduce the threat of oxygen spoilage during the stage of transportation.

Answer 26

1. avoiding ullage in vessels
2. use of inert (chemically inactive) gases
3. addition of sulfur dioxide
4. use of impermeable containers
5. cool, constant temperatures

Question 27

Identify the factors that determine the amount of sorting required for grapes upon reception to the winery.

Answer 27

• the ripeness and health of the fruit arriving at the winery,
• the intended final wine quality and price,
• whether any sorting has been carried out in the vineyard (e.g. by skilled hand-pickers)
• 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 28

Identify three ways that a must can be enriched.

Answer 28

adding dry sugar, grape must, grape concentrate or rectified concentrated grape must (RCGM – manufactured, flavourless syrup from grapes) and the processes of concentration (reverse osmosis, vacuum extraction, chilling).

Question 29

Identify five ways to prevent malolactic conversion.

Answer 29

• temperature below 15°C (59°F)
• a low pH and moderate levels of SO2
• add the enzyme lysozyme, which kills lactic acid bacteria
• move any batch of wine going through malolactic conversion to another part of the winery to avoid the spread of lactic acid bacteria
• lactic acid bacteria can be filtered out to avoid malolactic conversion taking place

Question 30

Identify the reasons a winemaker would choose to blend.

Answer 30

• balance
• consistency
• style
• complexity
• minimise faults
• volume
• price

Question 31

Identify the four main choices for clarification.

Answer 31

sedimentation, centrifugation, fining, and filtration.

Question 32

Identify the three most common forms of stabilization carried out on finished wines.

Answer 32

Protein, tartrate, and microbiological stabilization.

Question 33

Identify two ways to stabilize a wine that has been affected by brettanomyces.

Answer 33

wine can be treated by filtering or with DMDC (dimethyl dicarbonate, commercial name: Velcorin) before bottling, which inactivates Brettanomyces

Question 34

Identify the common range for free SO2 in white, red and sweet wines.

Answer 34

*
white wine – 25–45 mg/L (lower than for red wines due to lower pH)
*
red wine – 30–55 mg/L
*
sweet wine – 30–60 mg/L

Question 35

List four ways that volatile acidity can be avoided in the wine making process.

Answer 35

The threat can be reduced by
1. sorting fruit to exclude damaged grapes, scrupulous hygiene in the winery,
2. keeping vessels topped up,
3. careful racking (to avoid excessive exposure to oxygen)
4. maintaining adequate SO2 levels.

Question 36

Identify 16 common Technical Specifications used for large wine contracts to ensure product quality and consistency.

Answer 36

1. free and total SO2
2. volatile acidity
3. alcohol content
4. residual sugars
5. total acidity
6. pH
7. malic acid and lactic acid
8. total dry extract
9. tartrates and proteins (stability analysis)
10. turbidity (the amount of particles in suspension and therefore how clear a wine is)
11. various minor acids: sorbic, ascorbic, metatartaric, citric
12. trace metals such as copper, iron, potassium, calcium, sodium
13. dissolved oxygen
14. CO2
15. microbial populations (various strains of yeast, bacteria)
16. taints, e.g. TCA

Question 37

Identify 4 methods used for concentrating grape must to create wines with residual sugar.

Answer 37

The drying grapes on and off the vine, the development of noble rot and the freezing of grapes.

Question 38

Identify 5 methods for stopping fermentation in order to make a wine with residual sugar.

Answer 38

1. chilling to below 10°C (50°F)
2. adding a high dose of SO2 to inhibit the yeast
3. racking off the sediment
4. sterile filtering the wine
5. (fortification) adding alcohol to kill the yeast

Question 39

Identify the three main factors that affect the extraction of tannins and anthocyanins.

Answer 39

1. temperature
2. time on skins
3. the medium in which the extraction is taking place (e.g. wine for tannins and grape must for anthocyanins)

Question 40

Identify two faults that can be minimized using flash detente.

Answer 40

smoke taint and botrytis (grey rot).

Question 41

Identify the four timing options for pressing in red wine vinification.

Answer 41

• For wines that have been made by carbonic maceration, pressing may occur when the fermenting must reaches 2% abv to produce a wine with medium levels of colour and fruity flavours but low tannins.
• At the opposite end, some red wines will be pressed after a period of post-fermentation maceration to maximise
  the tannin structure of the wines.
• The winemaker also has the option to press straight after alcoholic fermentation is complete (the wine is dry), or
• press just before the end of alcoholic fermentation, usually with the intention that the wine will finish fermenting in barrels. This latter practice is thought to lead to a better integration of oak flavours and rounder mouthfeel.

Question 42

Identify the three key methods for rose production.

Answer 42

1. direct pressing
2. blending
3. short maceration