Stage 1

Factors affecting Style, Quality & Price

There are a number of factors which influence the final style, character and price of a wine, these are:

Section 1 - Grape Variety
Section 2 - Grape Growing
Section 3 - Winemaking
Section 4 - Factors Affecting Cost

Once you have read all these sections test your knowledge with the quiz.

Section 1 - Grape Variety

There are many different varieties of grapes and, through centuries of wine making, the varieties which give the best yields, taste and resistance to disease have been recognised and narrowed down to the varieties we are most familiar with today. These varieties include Cabernet Sauvignon, Merlot, Sauvignon Blanc and Chardonnay.

The grape variety will have a huge effect on the character of the wine as it will affect the flavour, colour, sugar levels, acidity and tannins present.

Section 2 will look more closely at the different characteristics of each of the classic grape varieties and why they can produce such different wines.

Grape components

The various components which grapes are made up from can be seen here. It is important to remember than the juice of all grapes is clear and it is the skins that hold the colour. In the case of red and rosé wines, the colour is extracted from the skin of the grapes during the winemaking process.

Environment

As with all plants, vines must have exposure to the following in order to produce a ripe and healthy crop of grapes each year:

Carbon Dioxide (CO2)	– present in the air
Sunlight	– affected by the climate and weather conditions
Water
Warmth
Nutrients	– present in the soil of the vineyard

Climate

This describes the type of weather conditions (temperatures, rainfall and sunshine) that would occur during a typical year.

Different grape varieties need different climatic conditions in order to grow and ripen well. For example, Cabernet Sauvignon needs a lot of heat to ripen fully or it will taste very sour, astringent and bitter and will lack fruit flavours. Varieties such as Sauvignon Blanc need a cooler climate so that they do not over-ripen and lose their acidity and refreshing flavour characteristics.

Some grape varieties, such as Chardonnay, can grow in most climates but the characters of the end wines will be totally different.

There are three main types of climate to consider when looking at wine and winemaking:

Cool – e.g. France and Northern Europe
Moderate – e.g. Coastal areas of South Africa, Southern Italy
Hot – e.g. Australia

In general, the hotter the climate, the more alcohol, fuller body, higher tannins and lower acidity the wine will have. The opposite is true for wines produced in cooler climates.

Climate is also influenced by latitude so wine producing regions nearer the equator will be hotter. Proximity to the sea is another factor that affects climate and coastal areas will be cooler. Altitude also has an effect and areas at higher altitudes will be cooler.

Weather

Weather conditions are usually very variable and will affect the style and quality of the grapes and wine from year to year.

Unusual weather conditions such as excessive heat or cold will affect the harvest (vintage). The weather is usually more variable in areas such as Champagne and Bordeaux than many New World regions.

Weather conditions such as Rain, Hail, Frost or Wind can damage the grapes and cause problems with the size and quality of the harvest.

Sunlight

Sunlight gives energy to the vine, which allows the grape to convert Carbon Dioxide and water into the sugars necessary to make alcohol during the fermentation process.

The position of the vines in a vineyard is very important as it can optimise the levels of sunshine a vine is exposed to in a cooler area or protect the vines from over-exposure in a hotter area.

Water

Water can come from rainfall, underground sources or irrigation. It is important that vines do not receive too much water as this will dilute the flavours and sugars in the grapes, therefore reducing the potential alcohol, body and flavour of the wine.

In regions with higher rainfall, the best vineyards will be in areas where there is good drainage, such as on slopes or on gravel soils. In drier regions, irrigation will be used to help the vines obtain sufficient water.

Cheaper wines will often come from vines that have been well irrigated as this increases yields. However, for higher quality wines, irrigation will be strictly limited so as to control the production of sugars and flavours in the grapes.

Warmth

Warmth is needed for the production of sugars so it is important that vineyards are located in areas where there is sufficient warmth during the growing season. Most of the world’s vineyards are located between 30° and 50° latitude as these zones are the most temperate.

In hot conditions, vines help to keep themselves cool by evaporating water through their leaves, although if conditions are extreme, a vine will shut down its leaves altogether to prevent itself from dying out.

Warmth can also be obtained from the soil and vines planted on stony grounds will often be warmer than those on soils such as wet clay.

Nutrition

Along with the water a vine receives through its roots and the sugars produced by its leaves, the vine will also obtain important nutrients from the soil. However, grapevines are very tolerant and can survive in very poor soils, as long as there are at least small amounts of nutrients present.

Section 2 - Grape Growing

Vineyard Activities

A vineyard is a busy place throughout the year and constant care and attention of the vines is vital as it will directly affect the quality and yield of the grapes to be harvested that year.

The main vineyard activities that help the fruit ripen fully and evenly are:

Pruning
Controlling the number of bunches of grapes on each vine
Careful positioning of the leaves of the vine to regulate the temperature of the bunches of grapes by controlling their exposure to sunlight

These activities are time and labour intensive and therefore also increase the cost of the wine. However, they are important if the quality of the grapes and wine is to be maintained to a high standard.

By contrast, vineyards producing grapes for high-volume wine making will tend to focus on minimal pruning and maximum mechanisation in order to reduce costs.

Yields

Yields have a direct affect on quality. Lower yields will usually result in riper fruit with more concentrated flavours. However, reducing yields takes time and each kilogram of grapes will command a higher price as the crop will be smaller.

At the other end of the scale, higher yields can be obtained by using irrigation to fill the grapes with water, therefore diluting the flavours and sugars. The wine from these grapes will be cheap and are unlikely to be very interesting.

Many wines however, are made from mid-yield harvests so as to reach a balance between quality, volume and price.

Soil and Slope of the Vineyard

It is important that the soil of a vineyard contains the correct amounts of nutrients and water for the vines to thrive.

Vines need water to survive but good drainage is also vital in a vineyard to prevent the vines from becoming water-logged. For this reason many of the best vineyards in Europe are on slopes, which provide natural drainage for the higher levels of rainfall. Gravel or chalk soils also provide good natural drainage. In areas of the world where rainfall is lower, vineyards are often irrigated.

Soil also absorbs or reflects heat, which is important for the successful growth of the vines. Stony soils are usually drier, and therefore warmer, than clay soils, which retain more moisture and can be cooler.

The aspect of a vineyard is another crucial factor of grape growing. For example, in Europe, grapes on a vineyard with a south-facing slope will benefit from exposure to the sun throughout the day, which in turn will help obtain maximum ripeness and sugar levels.

Pests and diseases

There are a number of pests and diseases that can also threaten grapes and vines:

Animal Pests such as birds, rabbits and insects, can damage shoots, buds, and leaves and even eat the grapes.
Fungal diseases such as mildew or rot can damage green parts of the vine and also spoil the grapes
Long-term diseases caused by fungi, bacteria or viruses, which affect the health of the vine and can eventually cause the vine to die.

Harvest

Once the grapes have ripened the harvest will take place. In larger and flatter vineyards, harvesting is often done mechanically using machines, which shake the grapes off their stems. However, in smaller vineyards, vineyards on slopes or for wines that require whole bunches of grapes to be picked, the harvest will be done by hand. Hand harvesting is far more labour-intensive, and therefore expensive, but in regions where labour is cheap, harvesting by hand is commonly used. Top quality wines can be made from both machine harvested and hand harvested grapes.

Section 3 – Wine Making

The Process of Fermentation

The process of fermentation is the most important part of winemaking. Fermentation occurs when yeasts feed on the sugars from the grape juice. The yeasts then produce alcohol, carbon dioxide and heat which change the flavours of the grape juice into those of wine.

The Fermentation Process:

There are a number of different styles of wine:

Red	Sparkling	Sweet
White	Fortified	Medium
Rosé	Still	Dry

White Wine

Almost all grapes varieties have white flesh and contain clear juice; it is the skins of black grapes that contain the colour. Therefore, the colour of red and rosé wines is obtained by soaking the coloured skins in the fermenting grape juice. The longer the skins are left in contact with the juice, the deeper the colour of the wine.

White wines can be made from black or white grapes. The grapes are first crushed to break the skins before being pressed to separate the juice from the skins. Yeast is then added. Often, the yeast is a commercially obtained yeast culture but some winemakers choose to use only the ‘natural’ yeasts which are present in the winery as it can help produce a more interesting wine.

The must is then transferred into a fermentation vessel; most commonly a stainless steel tank but oak barrels, open-topped concrete tanks or wooden fermenters are also frequently used.

White wines are fermented for two to four weeks at low temperatures of between 15 and 20° C. The use of low temperatures in the fermentation of white wines helps to preserve the delicate fruit aromas.

Red Wine

Red wines can only be made from black grape varieties.

The grapes are first crushed as this releases the juice. The juice and skins are then put into the fermenting vessel together. In contrast to white wines, fermentation is at a higher temperature (25-30 C).

The amount of colour and tannin in the finished wine depends on the length of time the skins have been in contact with the wine. For richer, fuller bodied wines such as top quality Bordeaux, this can be up to two weeks. For lighter bodied reds such as Beaujolais, skin contact can be for just five days. The varying amount of tannins, colour and flavour naturally present in each grape variety will also affect the amount of colour and tannin in the wine.

The extraction of colour, tannins and flavours from the grape skins is aided by alcohol and in order to keep the skins in constant contact with the juice, the juice can be ‘pumped over’ the floating skins. Alternatively, the skins can be ‘punched down’ into the juice.

Once the required colour and tannin levels are reached, the ‘free-run’ wine is drawn off. The grape skins are then pressed which will produce the ‘press wine’. This wine contains higher levels of tannin and can be blended with the free-run wine.

Rosé Wine

Just as with red wines, rosés can only be made from black grape varieties. The method of production is similar to red wine except that fermentation is carried out at a lower temperature (like white wine at 15-20 C). The length of time that the juice is in contact with the grape skins is also much shorter (12 to 36 hours) as the intensity of colour and tannin required for rosé wines is less than for red wines.

Confusingly, ‘White Grenache’ and ‘White Zinfandel’ are rosé wines. Another common labelling term for rosés is ‘blush’.

Other styles of wine

Sweet and Sparkling and Fortified wines are discussed separately in Stage 4.

Oak Flavours

Many wines will have some contact with oak during the vinification process.

This can be done in any of the following ways:

Oak staves (small planks) or chips (large splinters)

These are added to a vat and can be of varying quality.

Oak Essence

This is the cheapest (and most inferior) method of adding oak flavour.

Fermentation and/or ageing in oak barrels

These are the only methods permitted in the production of higher quality wines. If the oak used is new oak, then a large premium will be paid as oak is expensive. The most commonly used types of oak are French and American; French oak is more expensive and tends to give more subtle toasty and nutty flavours whereas American oak is quite different as it tends to give more of a sweet coconut and vanilla flavour to the wine.

Wines that are produced using the highest quality air-dried staves will command higher prices. There is also a considerable amount of extra care and attention involved in the wine making process when oak is used as the casks always need to be topped up to avoid spoiling by air inside – this will also cause the wine to be more expensive.

Fermentation in oak barrels is often used for premium Chardonnays. However, it is impractical to ferment red wines in barrels so oak is used just in the ageing process of these wines instead.

Maturation

When wines are matured, a number of slow chemical reactions take place in the wine that in turn, enables complex flavours in the wine to develop.

Maturation can take place in oak barrels or large neutral wooden or stainless steel vats. Wine will also mature in the bottle after bottling. Each of these methods will produce quite different results in the final wine.

Maturation with Oxygen

Unlike new oak, old oak barrels or vats do not add any flavour to a wine but as oak is a porous material, wines matured in oak barrels or vats will be in contact with small amounts of oxygen. These small amounts of oxygen will dissolve in the wine and in red wines this will soften the tannins, giving a smoother finish. Hints of toffee, hazelnut and coffee can also develop.

Maturation without Oxygen

If maturation without oxygen is required, the wine must be contained in bottles or stainless steel vats as they are airtight. The chemical reactions in bottles and stainless steel vats are different to those in oak and they do not add any flavours to the wine.

The flavour of a wine can remain almost unchanged for months when stored in stainless steel vats. However, when in bottles, changes will occur faster as they are smaller and with the absence of oxygen, the fresh fruit aromas of a young wine will become more like cooked fruit with vegetal and animal hints such as wet leaves, mushroom and leather.

There are few wines that actually improve with maturation in the bottle as often the attractive fruit flavours will fade away and the oxidative, animal and vegetal notes which replace the fruit can also often be unpleasant. However, there are some special wines which are produced in such a way that the fruit character is actually preserved with ageing while at the same time allowing other complex flavours to develop in the wine. These wines are difficult to produce and usually expensive but of exceptional quality.

Some examples of wines suitable for maturation are:

Rioja
Red Bordeaux
Red & White Burgundy
Chianti Classico

Section 4 – Factors affecting cost

There are a number of factors that affect the cost of producing a bottle of wine:

Vineyard

Cost of vineyard land; the sites with higher potential for quality can be much more expensive than ordinary locations
Mechanisation of vineyard work; some vineyards cannot be mechanised, for example in steep sites, and therefore more expensive to manage
The cost and availability of labour and equipment
The yield of the vineyard and extent of selection of the grapes; control of the yield and the labour intensive sorting of under-ripe or rotten grapes needs to be considered in the final selling price of the wine.

Winery

The type, quality and efficiency of the winery equipment installed
Cost of barrels or other types of oak flavouring if used
Ageing of the wine as it requires expensive storage facilities and ties up capital

Packaging, Distribution and Sale

Exchange rates which affect the final selling prices of exported wine
Packaging (bottles, labels etc.) and cartons for distribution
Transport costs although most wine is shipped by sea and the costs for this type of transportation are actually relatively inexpensive
The efficiency and profit margins of the distributor and retailer of the wine.

Other e.g. Tax

Taxes and levies such as Excise Duty and VAT which are also absorbed into the final price of a bottle of wine
Consumer demand; this is the ultimate factor in deciding the price of a bottle of wine as even if a wine has been expensive to produce, if the quality does not match then it will not sell. Marketing and the reputation of producers, regions or brands can help a wine sell at high prices but it is vital that the quality of the wine lives up to consumer expectations. Winemakers are dependent on the demand of their consumers to maintain prices.

It is important to note the differences between wines produced in large volumes and/or sold at inexpensive prices and premium quality wines that are usually more expensive.