D1 Wine Production Flashcards
How is production oriented farming achieved in conventional viticulture?
Mechanisation, chemical input, irrigation and clonal selection.
What are the advantages of a monoculture?
Ability to mechanise, to tend to specific needs of the vine e.g. irrigation, nutrition levels, chemicals
What are the disadvantages of a monoculture?
Much more prone to diseases, no natural eco-system depleting nutrients, residual chemicals damaging environment
What are the three themes of sustainable viticulture?
Economic, social and environmental sustainability
What is Integrated Pest Management?
IPM, also known as lutte raisonee, builds on some of the insights of organic viticulture, but is prepared to use chemical interventions when necessary.
What are the advantages of sustainable viticulture?
More thoughtful approach to grape growing in terms of the three themes, deployment of a scientific understanding of threats, minimise number of interventions needed. Reduction of spraying. Cost savings due to incentives
What are the disadvantages of sustainable viticulture?
Term not protected, can’t be used to promote wine(unlike organic or biodynamic). Danger that nationwide standards for sustainability can be set too low.
What are the key differentia of organic viticulture?
Seeks to improve soil and the range of microbes and animals, e.g. earthworms, thereby increase the health and disease-resistance of the vine. Rejects man-made (synthetic) fertilisers, fungicides, herbicides and pesticides
What is biodynamic viticulture?
Biodynamic farming is based on the work of Rudolf Steiner and Maria Thun, it includes organic practices but also incorporates philosophy and cosmology. Vineyards being part of the connected system with the planet earth, practitioners adapt viticulture to coincide with the cycles of the planets, moon and stars.
What is precision viticulture?
PV makes use of data collected in the vineyard (about soil, vigour, topography, plant growth) to respond to changes from plot to plot and from row to row. Interventions in the vineyard can be targeted in the light of the data collected. Geospatial technology such as GPS and GIS allows the data to be presented in maps.
What are the advantages of PV?
Detailed understanding of variations in the vineyard. Ability to tailor a wide range of interventions to individual blocks or even rows of vines(choice of variety and rootstock, canopy management, treatments, harvest dates)
What are the disadvantages of PV
Initial cost of remote data collection. Cost of sensors and software and of either consultancy or trained staff to interpret the data and make interventions in the light of it.
Name the 3 steps of vineyard establishment.
1 Site selection, 2 Soil preparation, 3 Planting materials
What are organic fertilisers?
Fertilisers made from fresh or composted plant or animal material, such as manure or slurry. Cover crops can be grown and mown into the soil to decompose and provide nutrients (termed green manure).
What are mineral fertilisers?
Fertilisers that are extracted from the ground or chemically manufactured. Can be more tailored and nutrients are already inorganic, therefore more readily available for vines. But no benefit for soil organisms.
Name other methods of nutrients management than fertillisers(5).
Cultivation / Herbicides / Animal Grazing / Cover crops / Mulching
What is mulching?
Mulching is the spreading of matter onto the vineyard soil to suppress the growth of weeds. Mulches are usually made of biodegradable materials, such as straw or bark chips, that ultimately provide nutrients for vines.
What is RDI?
Regulated deficit irrigation is a system of timing and regulating the amount of irrigation so that the vine is put under mild to moderate water stress for a specified time within the growing season (usually between fruit set and veraison)
What are the main interventions in conventional winemaking?
- Temperature control - cold soaking, during fermentation and maturation
- Use of additives and/or processing aids e.g. sugar, SO2, cultured yeast, fining agents
- Manipulations: simple pressing and filtration to high technology e.g. reverse osmosis
What is the main certifying body for biodynamic winemaking and grape growing?
Demeter International. Regulations depend on country even within Demeter.
What are the aims of canopy management?
Maximise effectiveness of light interception by the vine canopy. Reduce shade within the canopy. Make microclimate as uniform as possible for the grapes to ripen evenly. Balance between vegetative & reproductive functions of the vine. Promote air circulation to reduce incidence of disease.
PROs for sunlight exposure through canopy management are?
- Increased sugar levels due to higher photosynthesis
- Increased tannin levels and greater polymerisation - less bitterness
- enhanced anthocyanin development
- decreased malic acid (for cooler climate)
- increased levels of certain aroma precursors and compounds, e.g. terpenes -> floral, fruity aromas
- decreased methoxypyrazines -> herbaceous
CONs for sunlight exposure through canopy management are?
- Sunburn
Describe a vegetative cycle vs. balanced cycle
In a vegetative cycle the canopy is too dense due to increased leaf area. This creates shades that depresses budbreak, bunch initiation, fruit set and berry growth which then reduces the fruit weight per shoot. Shoot growth is stimulated due to less fruit growth which again increases the canopy density. In a balanced cycle the opposite happens leading to more fruit weight.
What is vine density?
Vine density is the number of vines that are planted per hectare of vineyard. This can range from as low as a few hundred per h to over 10,000 per hectare.
What needs to be considered when deciding how to train, prune and trellis a vine?
- Vigour of the vine
- Topography of the site
- Need for mechanisation
What are the two main categories of vine training? Explain.
Head training: Relatively little permanent wood, consists usually of the trunk. Vines can be spur-pruned or replacement cane-pruned.
- Cordon training: Trunk + one or more permanent horizontal wood arm, called cordons. Usually spur-pruned, Needs longer than head trained to establish
Name 7 main methods of summer pruning.
- Disbudding or Debudding
- Shoot removal
- Shoot positioning
- Pinching
- Shoot trimming
- Leaf removal
- Crop thinning / green harvesting
Name American rootstock which offers most protection from phylloxera.
Vitis berlandieri, V. riparia, V. Rupestris
Name two of the most commonly occuring nematodes.
Root knot and dagger nematode
Name rootstock resistant to nematodes.
Ramsey and Dog Ridge, both Vitis champini.
How to manage powdery mildew.
- Keep an open canopy as powdery mildew thrives in dense shady conditions and temperature around 25 degrees.
- Application of sulfur. Spray after a couple of weeks after budburst up to veraison
- Fungicides
How to manage downy mildew.
- Sprays of copper salt (Bordeaux mixture) but only lasts until 20mm of rain
- Fungicides
- Good drainage and open canopy
What is micro-oxygenation?
A technique that involves bubbling oxygen through wine, generally in stainless steel tanks post alcoholic fermentation. Increases colour stability and intensity, soften tannins, improve texture and reduce any unripe and herbaceous flavours. Cheaper than oak barrels but reaching similar effects. Can be controlled and can create influence of oak with oak staves or chips. However, can provide a more favourable environment for spoilage.
What is lees autolysis?
After fermentation, the yeast cells die very slowly and break down releasing compounds that can contribute flavours, body and texture to the wine.
What is racking?
Racking is the process of transferring wine from one vessel to another while removing unwanted sediments such as gross lees, fine lees, solids, and tartrate crystals. Can be both an oxidative process or a protected one by using inert gas.
Name 4 ways of clarification of must in white wine making.
Sedimentation, flotation, centrifugation, clarifying agents
What is batonnage?
Lees stirring
What is ullage?
the headspace of air between wine and the top of the container holding the wine.
What is pomace?
Pomace, or marc, is the solid remains of grapes, olives, or other fruit after pressing for juice or oil. It contains the skins, pulp, seeds, and stems of the fruit. Grape pomace has traditionally been used to produce pomace brandy.
What is flash detente?
Maceration technique using heat. Destemmed grapes are heated to 85-90 C, then cooled again in a vacuum within a short time, e.g. 2 minutes.
What is Thermovinification?
Maceration technique using heat up to 50 -60 C.
Why does maceration using heat have issues with colour stability?
There’s not enough tannins to bind with anthocyanins to form more stable compounds
What is pigeage?
Punching-down (cap-management technique)
What is remontage?
Pumping-over
What is delestage?
Rack and return
Name five cap management techniques.
Pumping-over, punching-down, rack and return, Ganimede tanks, rotary fermenters
Name ways of concentrating grape must for sweet wine(4)
Dry grapes on the vine(late harvest, vendange tardive, Spaetlese), dry grapes off the vine(passito - recioto di Valpolicella, vin santo), noble rot (botrytis cinerea), freezing grapes on the vine (icewine)
Name ways to produce sweet wine (3).
Concentrating grape must, stopping fermentation (residual sugar), blending in a sweetening component(sugar, RCGM, Suessreserve)
What is tannin polymerisation?
If two phenolic compounds bond together a polyphenolic dimer is formed, three form trimers etc. Typically up to ten phenolic molecules can bond to form tannins. Polymerisation of phenolics to form tannins continues as the wine ages, so the concentration of tannins increases.
What is intended with Hyper oxidation?
To produce wines that are more stable against oxidation after fermentation. Remove bitter compounds. Enhance ageability of wine
Name the two most common types of press to use.
Pneumatic press, basket press
