Describe

Question 1

Describe 6 factors in the vineyard that affect temperature.

Answer 1

1. latitude
2. altitude
3. slopes and aspect
4. proximity to water
5. winds
6. characteristics of the soil
7. clouds
8. mist and fog
9. diurnal range

Question 2

Describe the function of the vine roots.

Answer 2

The roots are important for anchoring the vine and also for the uptake of water and nutrients. The roots are also a store of carbohydrates and produce hormones that have important functions within vine growth and grape ripening. In most cases, vines are grafted onto a rootstock.

Most of the vine’s roots are found in the top 50 cm of the soil, although vine roots have been found that reach over six metres down into the soil. Distribution of the main framework of roots is influenced by the soil properties, irrigation, cultivation and the type of rootstock. The water and nutrients are absorbed at the root tips, where the roots are actively growing.

Question 3

Describe the effects of temperatures above 33 degree celsius on the vines’ ability to ripen grapes.

Question 4

Describe two regions that rely on the temperature moderating effects of ocean currents.

Question 5

Describe the result of low or high nitrogen levels in vineyard soils.

Question 6

Describe the importance of humus in vineyard soil composition.

Question 7

Describe the types of herbicides used in vineyard management.

Question 8

8. Describe three ways that a producer in a region that does not allow irrigation could combat water stress in the vines.

Question 9

Describe the conditions and symptoms of leaf spot.

Question 10

Describe the effects of Leaf Roll Virus.

Question 11

Describe how ethanol contributes to the overall perception of wine.

Question 12

Describe the aromas produced from aroma precursors during fermentation.

Question 13

Describe the four quadrants of Vicente Ferreira’s Model for Wine Aromas.

Question 14

Describe the contributions of phenolics to a final wine.

Question 15

Describe the main techniques used in reductive wine making.

Question 16

Describe the techniques a winery can implement to reduce their dependence on sulfur dioxide.

Question 17

Describe the advantages of using cultured yeasts in the fermentation process.

Question 18

Describe the changes that occur to wine that has undergone malolactic fermentation.

Question 19

Describe the advantages of using oak alternatives.

Question 20

Describe the fining agents that remove unstable colour and bitter phenolic compounds.

Question 21

Describe a winemakers options for depth filtration.

Question 22

Describe two stabilization methods for preventing refermentation in the bottle.

Question 23

Describe how light strike can be avoided.

Question 24

Describe the components that make up Total Package Oxygen.

Question 25

Describe a one-plus-one closure.

Question 26

Describe HACCP as an approach to quality assurance.

Question 27

Describe the reasons a producer would choose to avoid skin contact in the vinification of their white wine.

Question 28

Describe the advantages and disadvantages of using cane cutting as a method to dry grapes for making wines with residual sugar.

Question 29

Describe the effect of noble rot on the style of the final wine.

Question 30

Describe the options a winemaker has for blending in a sweetening component into a wine to create a style with noticeable amounts of residual sugar.

Question 31

Describe the considerations a winemaker must make when choosing to use rack and return as a method of cap management during maceration.

Question 32

Describe the purpose of a ganimede tank.

Question 33

Describe the ideal characteristics of grapes that will be used to make a wine with carbonic maceration technique.

Question 34

Describe the effect on aromas in red wine when warmer fermentation temperatures are used.

Question 35

Describe the effect of oak maturation on mid priced to premium priced red wines.

Question 36

Describe how lees aging will change the qualities of a red wine.

Question 37

Describe what happens during early grape growth (pre-véraison). (10%)

Question 38

Describe the vine characteristics a vineyard manager might consider when determining whether a grape variety will be suited to the growing environment of a new vineyard site. (15%)

Answer 38

• Time of budding – Early budding grape varieties, such as Chardonnay, are more at risk from spring frost damage compared to late budding varieties, such as Riesling.
• Duration of annual life-cycle – Early ripening grape varieties, such as Chardonnay and Pinot Noir, are best suited to cool climates, ensuring that they reach a suitable level
  of ripeness before wet, cold weather starts towards late autumn. Late ripening grape varieties, such as Mourvèdre, are better suited to warm and hot climates. Early ripening
  varieties in these climates would gain sugar and lose acidity too rapidly, resulting in unbalanced wines.
• Tolerance of drought – Grape varieties that are able to withstand a high level of water stress, such as Grenache, can be the best option in dry climates such as the southern
  Rhône, inland Spain and McLaren Vale.
• Resistance to disease – Some grape varieties are less susceptible to fungal diseases, meaning that they require less monitoring and/or treating in damp climates. For example, Cabernet Sauvignon is less susceptible to grey rot than Merlot, one of the reasons why these two grape varieties make useful blending partners, particularly in maritime Bordeaux.
• Winter hardiness – Some grape varieties, such as Vidal and Riesling, are relatively tolerant of very cold winter temperatures, making them suitable for the harsh winters
  experienced in Ontario and the Finger Lakes.
• Vigour – If high vigour grape varieties, such as Sauvignon Blanc, are grown on fertile soils with plentiful water, it is likely that their vigour will need managing to avoid excessive
  shoot growth.

Question 39

Describe the use of the following substances in the winery:
a) metatartaric acid
b) bentonite
c) calcium carbonate
d) diatomaceous earth
(20%)

Answer 39

a) metatartaric acid

Adding metatartaric acid prevents the growth of potassium bitartrate and calcium tartrate crystals, reducing the need for cold stabilisation. However, the compound is unstable, and its positive effect lost over time, especially when wine is stored at high temperatures (25-30℃/77-86℉), meaning it is best used for wines designed for early consumption. It is a quick and easy process that tends to be used more for red wines as for white wines CMC is more effective and long lasting.

b) bentonite

Bentonite is a form of clay that absorbs unstable proteins and unstable colloidal colouring matter. It has a minimal effect on the flavour and texture of wine. It does lead to some colour loss in red wines and produces large amounts of sediment, and so wine is lost when it is racked off. Bentonite can be used to dine must as well as wine.

c) calcium carbonate

In cool climates where grapes may have to be picked before they are fully ripe (e.g. due to the threat of poor weather), it may be necessary to deacidify the must or wine. Deacidification is carried out by adding calcium carbonate, also known as chalk or limestone, and it lowers acidity by the formation and precipitation of tartrates.

d) diatomaceous earth

The most common form of depth filtration uses diatomaceous earth (“DE”, also known as Kieselguhr), which, once it has been processed, is pure silica and inert. The DE is wetted and used as a filter medium. Wine is sucked by vacuum from the outside of a rotary drum, through the DE, to the inside of the drum.

Question 40

Describe what Eutypa Dieback is and ways to avoid it （15%）.

Question 41

Describe the components contained in the pulp, skin and seeds of a wine grape (10%).