Dear Friends of Monolithos,
Wine, with as many as 8,000 years of human consumption, is generally recognized as safe when consumed in moderation. Pasteur is often quoted as saying wine is the most healthful and hygienic of beverages. In contrast to water and milk, for example, which have been carriers of disease, wines are not subject to food spoilages, nor will wines carry viable human pathogens even if they had been added. In earlier times with poorly understood sanitation and frequent contaminations, wine was especially attractive for never causing food poisoning, enteritis, etc. This and other benefits have made wine very widely and regularly consumed in many societies, from ancient to modern.
It takes more than grapes, water and alcohol to make your favourite wines. Wine consists of a complex myriad of substances including water, alcohol, acids, sugars, polyphenols and phenolic compounds, salty substances, dissolved gases and aromatic substances. Each of the following components affects the way we perceive the wines total composition.
Water (80% to 85%): The water in wine derives entirely from grape juice, so it is biologically pure. It is the base for all the complex biochemical phenomena that occur as wine is made and aged. The water content of wine is seldom discussed as its presence is taken for granted. Nevertheless, as the principal chemical constituent of grapes and wine, water plays critical roles in establishing the basic characteristics of wine. For example, compounds in the grape that are not at least slightly soluble in water will play no part in the resulting wine – it’s the water which will determine the basic flow characteristics. Even the tears that form on the inner surface of a glass after wine has been swilled around are partially dependant on the properties of water.
Alcohols (10% to 17%): The alcohol in wine is made by yeast-converting sugars. Several types of alcohol in wine include ethyl and glycerol, which adds sweetness. The most important alcohol in quantity terms is ethyl, a mono-alcohol, followed by glycerol, a polyvalent alcohol that adds a degree of sweetness, and finally by higher alcohols such as proponol, butanol and isoamyl. Besides adding their own characteristic flavours and odours, alcohols are the main carriers of aroma or bouquet. In some fortified wines, alcohol attained by distillation may be added.
Acids (0.4% to 1%): Acids give wine a sour or sharp taste. Some acids come from the grapes and others are made during fermentation. Three organic acids, tartaric, malic and citric, are natural components of grapes. The three others present in wine (succinic, lactic and acetic acid, the source of volatile acidity), are produced by fermentation. Acids give wine the sour or sharp aspect that enhances flavour when in balance with other components. Tartaric is prevalent as the base measure of total acidity in wine.
Sugars: The glucose and fructose contained in grapes is mainly converted into alcohol through fermentation. The sugar left in the completed wine varies from around 0.1% (1 g/l) for dry wines to 10% (100 g/l) in sweet wines. However, wine’s sweet taste comes from alcohol and other substances as well.
Flavouring and colouring substances (0.01% to 0.5%): Compounds in grape skins give wines their distinct colour and flavour. Red wines are coloured by anthocyanins and tannins, contained in grape skins, while white wines get their colour from the grape skins, wood and ageing. Phenolic pigments known as leuco-anthocyanins are present in white wines. Phenolics are compounds that occur in the stalks and skins of grapes; as well as being responsible for colour, they have a role in a wine’s mouth feel, but in excessive amounts can taste astringent or even bitter. Red wine has more than 15 anthocyanins that give colour to the wine and vary depending on the grape.
Mineral salts (0.2%-0.4%): Salts derived from minerals and organic acids lend freshness to the flavour of wine. The most important are potassium, sodium, magnesium, calcium, iron, sulphates, phosphoresces, all of which are necessary to cover daily needs of human beings.
Aromatic substances (0.01%-0.1%): Traces of various chemical compounds contribute to the aroma of a wine. These volatile substances include alcohols, aldehydes, esters, acids and ketones.
Sulphites: Extremely small amounts of chemicals made from sulphur and sulphur derivatives are used to safeguard grapes and sterilize and preserve wines. The presence of sulphites at 10 to 200 parts per million is measured both in fixed sulphur dioxide, combined with other substances in the form of gas.
Misc, Vitamins, etc.: Wine also contains vitamins of the group B, and, above all vitamin P which reinforces the cell wall of capillary vessels, lessening the risks of haemorrhage and oedema. Anti-oxidant effects of many of wine’s polyphenols are known to be valuable as dietary constituents combating fat rancidity, but they also appear important after consumption to oppose oxidative reactions detrimental to tissues within the body. Certain types of capillary bleeding and clotting of blood can be regularized by some of wine’s polyphenols, based on the experiments to date.
Most consumers have no idea what is commonly added to their wine during winemaking, and what ends up in the bottle. They often do not realize that most wine undergoes chemical analysis as well as a variety of tests in order to pour out of the bottle the way the winemaker intended. According to a report by the International Organisation of Vine and Wine, a number of additives, treatments and processes are currently allowed in most counties. Many of these things have been done to wine for centuries. It is good for consumers to know however, what is allowed and what the usual practice is. The list of additives permitted for use in the production of wine under EU law serves a number of processes such as:
. acidification (tartaric acid, malic acid, citric acid, fumantic acid)
. de-acidification (calcium carbonate, potassium carbonate, or potassium tartrate)
. clarification (bentonite, casein, edible gelatine, isinglass, gum arabic)
. enrichment (concentrated grape must, tannin, saccharose)
. fermentation (yeasts for wine production, ammonium bisulphite)
. decolourants (PVPP, activated charcoal)
. deodorant (copper sulphate, diammonium phosphate)
. enzymes ( pectinases, hemicellulases, glucanases and glycosidases)
. stabilisation (calcium tartrate, potassium bitartrate)
. preservation (potassium sorbate, ascorbic acid, potassium metabisulphite/disulfite
1. Acidification is the winemaking process of increasing the acidity in a grape must or wine. This is common practice in warm wine regions (as common as enrichment, or chaptalization, in cool wine regions), and is often the only course open to a wine-maker wanting to make a balanced wine from grapes which have been allowed a growing season long enough to develop flavour by reaching full physiological ripeness. Winemakers add tartaric acid to juice or must to raise acidity and lower pH. Large acid adjustments are made before fermentation is started. An addition of up to 1 kilogram of tartaric acid per 1,000 litres of juice will raise the total acidity about 0.1%. Care must be taken when tartaric acid is added to wine late in the winemaking process. If too much tartaric acid is added, tartrate crystals may form in the bottled wine. However, their presence causes only aesthetic problems. Sometimes, citric acid is added to finished wines specifically to increase acidity and improve acid balance. In small quantities, it provides a fresh, citric characteristic, and the citric quality is often appreciated in white table wines. About .7 grams of citric acid per litre is often added to commercial white wines to improve long-term stability. However, the citric taste does not seem appropriate in most red wines.
2. De-acidification is the process of reducing the titratable acidity in wine, grape juice, or must. There are numerous methods of doing this including cold stabilization and amelioration. The biological process of de-acidification in wine is a malolactic fermentation, in which malic acid is converted to lactic acid and softens the mouth feel of the acid. Physicochemical de-acidification involves either acid precipitation or column ion exchange. The de-acidification agents precipitate some tartaric acid in the form of insoluble salts. However, this introduces a risk of calcium tartrate instability. Simple de-acidification with Calcium Carbonate (CaCO3) is used against a high tartaric acid content, mainly on the must, juice also be utilized on young wine. Potassium Bicarbonate (KHCO3) and Potassium Carbonate (K2CO3) are used for de-acidification of must, juice, wine for improving quality or rounding off flavour. They both form carbon dioxide and precipitate potassium bitartrate.
3. Clarification is the process of removing cloudiness in the wine by filtration and/or fining and cold stabilising the wine. The major procedures involved are fining, filtration, centrifugation, refrigeration, ion exchange, and heating. These processes ensure that the wine is clear and bright without deposits. Many different materials are used for clarification and fining of wine and each material has different properties. Therefore, the winemaker must select each material carefully to produce the desired results. Bentonite is most commonly used to remove excess protein from both white and blush wines. A normal dose is 0.5 to 2 gm of dry bentonite per litre of wine. Gelatine is prepared from bone-derived sources of collagen. It is mainly used to soften red wines but can also be used to reduce the phenol level and the brown colour in white juice before fermentation. Gelatine removes a quantity of tannin roughly equal to its own weight. Gelatines are also used to clarify white and blush wines, and Kieselsol is used to precipitate any excess gelatine residue.
4. Enrichment is the winemaking counterpoint to acidification. Enrichment is the norm in climates where weather cannot be relied upon to bring grapes to full ripeness. The original process, often called chaptalization after its French promulgator Chaptal, involves adding sugar, whereas the wider term enrichment encompasses the addition of sugar, grape must, concentrated grape must, and rectified concentrated grape must. The objective is to ensure the alcoholic strength of wine products and consequently raising the quality of local wine. It involves use of sucrose as the commonest enrichment material. In northern Europe often sugar beet, or occasionally cane sugar is used. In principle, enrichment is forbidden for table wines produced within the EU, although there are local exceptions.
5. Fermentation: The process of alcoholic fermentation requires careful control for the production of high quality wines. The fermentation can be done with endogenous (or wild) yeast; however, this may give unpredictable results depending on the exact types of yeast species that are present. For this reason, a pure yeast culture is generally added to the must, which rapidly predominates the fermentation as it proceeds. Requirements include suppression of the growth of undesirable microorganisms, presence of adequate numbers of desirable yeasts, proper nutrition for yeast growth, temperature control for prevention of excessive heat, prevention of oxidation, and proper management of the cap of skins floating in red musts. During fermentation the most commonly used additives are: Tartaric and citric acid, active dry wine yeast, malolactic bacteria (optional) yeast nutrients, sulphite powder, enzymes, and fining materials (bentonite, gelatine and Sparkolloid).
6. Decolourant fining agents remove mainly the brown effect from oxidized white wine and are used to prevent the pink colour from some grapes. The most commonly used additive is PVPP. This synthetic material reacts with precursors to browning in all wines. It is used in moderation in rose and red wines to remove brown colour tones restore colour and bring back fruitiness. In white wines, it can extend shelf life of bottled wines, remove browning and oxidative compounds, and enhance fruit aroma.
7. Deodorant involves the removal of off-odours such as oxidation. The most commonly used additive is deodorizing carbon. When used in conjunction with PVPP it can simultaneously remove both off-flavours and off-odours. If in this process it is enhanced with bentonite it can help faster removal of sediments. Hydrogen sulphide is an unpleasant odour occurring in young wines. Early detection of this rotten egg odour and subsequent racking with deliberate splashing will usually cure the problem. However, in order to reduce the risk of H2S formation, it is wise to add yeast nutrient containing diammonium phosphate. Ascorbic acid in conjunction with copper sulphate works very well in the removal of Hydrogen Sulphide and its derivatives. Of course, it’s much better to prevent H2S from forming in the first place, by ensuring proper winemaking techniques and sanitation. Corked wine exhibits a very undesirable odour, reminiscent of mouldiness, and when unmistakably present it is sufficient excuse for refusing the wine in a restaurant.
8. Enzymes: these molecules occur naturally in all fruit – including grapes – and are partly responsible for the ripening process. The most widely used enzymes available for commercial use in the wine industry are: pectinases, hemicellulases, glucanases and glycosidases. The latter three types are generally sold as blends with pectinases. Pectic enzymes increase juice yields from fruits by breaking down cellular structure. It also acts as a clarifier, and is used to clear hazes caused by residual pectins. Sometimes, commercial wineries use enzymes to increase the amount of free running juice when crushing white grapes. The enzymes break down the cells in the grape pulp, and the juice is released. The additional free running juice reduces the number of press loads, so pressing is quicker after an enzyme treatment. Enzyme treatment produces a brighter and more brilliant colour in wines. Colour extraction happens much more quickly with enzyme treatment, and the colour stability is greatly increased. The enzyme treatment increases the extraction of mature, polymeric tannins. These tannins are also referred to in the wine industry as "soft tannins", which give the wines a rounder, softer mouth feel.
9. Stabilisation involves removing unwanted substances before bottling so they will not cause haziness or crystal formation in the finished wine. After clarification, the wine is put in oak casks where it will stabilize. Cold stabilization involves chilling wine prior to bottling it. This process crystallizes tartaric acid in the vat, so that these ugly, but harmless, crystals do not appear in the bottle. These crystals look like grains of clear sand, and are also known as "wine crystals" or "wine diamonds". They may appear to be sediment in the wine, but they are not. Cold stabilisation involves chilling the wine and holding it at about minus 3ºC for 1-2 weeks to separate out all or most of the tartrate crystals before bottling. Potassium sorbate is used to slow down yeast growth and inhibit fermentation, thus "stabilizing" the wine prior to bottling. Potassium Sorbate is a yeast inhibitor frequently used with wines containing residual sugar. After sorbate is added, a distinct off odour of geranium leaves may be produced in the wine. To be sure that this does not happen, it is imperative that you have at least 40 ppm of free SO2 in the wine when you add sorbate. Bentonite is the most commonly used additive to remove unstable proteins thus preventing them from precipitating in the bottled wine.
10. Preservatives: Despite alcohol being a natural preservative, most wine has had preservatives added as a protection against oxidation and bacterial spoilage. The preservative used is one of a number of forms of sulphur: sulphur salts or sulphur dioxide.
Potassium meta-bisulphite is added to wine to inhibit bacteria and yeast growth, and acts as a preservative as well as slowing down oxidation. During storage and in the bottle, sulphites at the proper levels will further protect a wine by continuing to inhibit spoilage organisms.
Most key chemicals that are added to the winemaking process are used to enhance and extend the life of the wine. Technically, wine can be produced minus any additive or chemical however the quality will suffer greatly. As more and more research is carried out into the constituents of the wine and the way they are formed, two areas in particular stand out.
First is the idea that regular consumption of wine in moderation is good for you. Statistical studies have shown that wine drinkers are less prone to heart disease, cancer and other diseases. This may be explained by the fact that wine drinkers tend to have a healthier lifestyle and are in groups which are less at risk to these diseases. Thanks to its alcohol content and non-alcoholic phytochemicals (natural occurring plant compounds), wine has been shown to reduce the risk of heart disease, certain cancers and slow the progression of neurological degenerative disorders like Alzheimer’s and Parkinson’s. However, some humans are allergic to sulfites or certain other additives. If this applies to you, please consult your doctor.
Second, there is the development of the scientific study of the process of wine making, and the technology to improve it. The use of biological and chemical fining materials has been found to be an important tool in the technological development of winemaking. There are many who would desire to depend on the natural processes of grapes and fermentation. Others have studied the chemicals which make up wine, seeking to determine those that cause the flavour, aroma and appearance of wine so that these can be enhanced in the production process.
We hope that this short essay will help readers to form an understanding of the most common additives used in the wine-making process. This is not meant to be a comprehensive guide to every additive that is used, but a description of the more common ones that ensure the bottle of wine you open is clear, good to look at and full of the aromas and tastes that the winemaker intended.
In moderation, and as part of an overall healthy diet, wine is good for you. However, the amount of wine you drink matters tremendously. Drinking more than what is recommended means that health benefits are lost and your physical condition will be at risk.
Wine News and Information
* A good rosé can be an ideal end to a sweaty workday and an electrifying start to a summer supper. It can transform your mood from glum to cheerful in a single sip, transferring the cares from your shoulders to the setting sun as it seeps into the horizon.
There are those who love rosé because they are becoming more comfortable with wine. A well-chilled rosé captures the summer sun, whether reflected off the Mediterranean at a plaza cafe along the Cote d'Azur or off a backyard swimming pool of a holiday home. Rosé is the essence of summer.
As rosés become more popular, more of them become available in the market, and their quality varies. So what should you consider in an Old World rosé? Vintage matters, but not as much as you might think. The common wisdom is that rosé is best the year after the harvest, so you will see many 2008s on the market this summer. Rosés range from a vibrant, transparent red to an ethereal pale hue. Some people say the palest rosés are the best, but that is a matter of taste.
A true rosé is bled, not blended. The winemaker bleeds off the juice from the skins of red grapes (a wine’s colour comes from the grape’s skin) after a short maceration. The European Commission created a heated debate recently by proposing to legalize the blending of red and white grapes to make rosé table wine; an outcry by producers and customers forced officials to withdraw the idea.
* How familiar are you with the terms Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI)? These are two of the European Quality schemes for agricultural products and have been in common use since 1992 for food (primarily cheese). However, you should get used to seeing them more often as, from 1st August 2009, they are label designations that will become a requirement on all wine made within the European Union (EU).
The labelling of wine is just one of the changes in a massive overhaul of the EU wine regulations being overseen by the European Commissioner for Agriculture and Rural Development. The changes are designed to improve the efficiency, quality and competitiveness of 21 winemaking nations in total holding >40% of the world’s vines and making 2/3 of its wine.
The 129 Articles of Council Regulation 479/2008 cover the following:
. Gradual removal of subsidies for distilling surplus or low quality production
. National support programmes to improve vineyard and production quality and also market competition.
. “Grubbing up” to take out of production surplus, uncompetitive vines
. The end of current restrictive planting rights by 2016 (2018 for some countries)
. Approval of winemaking practices to be transferred the European Commission
. Updated and simplified labelling with use of the PDO and PGI schemes
. Restricted Chaptalisation
Geographic Indication is defined as “referring to a region, a specific place or, in exceptional cases, a country which complies with the following requirements:
. it possesses a specific quality, reputation or other characteristics attributable to that geographical origin
. at least 85% of the grapes used for its production come exclusively from this geographical area
. its production takes place in this geographical area
. it is obtained from vine varieties belonging to Vitis vinifera or a cross between Vitis vinifera species and other species of the genus Vitis.
* Plastic wine bottles may be a greener alternative to glass, but they are not particularly friendly to top-notch reds and whites, a new study has shown. At least two Australian winemakers have begun producing wines in plastic bottles, arguing it is a convenient and environmentally friendly way to consume the drop. The plastic is 100% recyclable, while the glass in wine bottles can be only partially recycled.
A study commissioned by the plastic bottle manufacturer has cast doubt over the viability of wine stored in plastic. The study found that in the short-term, wine stored in glass and plastic tasted similar, but the wine stored in the plastic bottles started to deteriorate after about eight months and is best consumed within 12 months of bottling.
The polyethylene terephthalate (PET) bottles are permeable to air, which oxidises the wine. Wine bottlers can limit the amount of oxygen that enters the bottle with an oxygen scavenger – sachets containing material including fine iron powder covered with sea salt – but these are effective for only about 12 months. While 90% of wine sold in Australia is consumed within 48 hours, consumers have not embraced plastic.
* Shiraz has knocked off Chardonnay as Australia’s top wine. The grape variety regained its position as the most popular for the first time since 2006, according to the Winemakers’ Federation of Australia Vintage Report. Shiraz accounted for 23.6% of the total crush, compared with Chardonnay’s 23.4%. Chardonnay remained the country’s most popular white wine.
The report, which surveyed 340 wineries representing 89% of wine growers, revealed a 7% drop in the nation’s wine grape production, equivalent to about 125,000 tonnes.
Monolithos Monthly News
Harvesting grapes to make wine is not only the first step individual grapes make towards the finished bottle, but it is also the busiest time of the year for a winery. The exact time of the harvest depends on the type of grape, its ultimate use, and the weather. Some grape varieties mature early in the season, some later.
August and September mark prime time for the annual grape harvest for most vineyards in the area of Pachna and, to a greater extent, the vine growing villages of Cyprus. In general, at Monolithos the international wine grapes are harvested first (Merlot, Shiraz, Cabernet) as well as the white wine grapes (Malvasia, Xynisteri). The local red varieties (Mavro) are typically next in the harvest line, as they take a bit longer to reach full maturation. In Cyprus, traditional hand harvesting is the main route that a winery can take to get the grapes off the vine and ready for crushing. Hand harvesting affords selection that is more precise and tends to do a better job of protecting the grape’s juice content from oxidation due to damaged skins. The individual grape variety, the ripeness factor and the weather factor have the greatest influence on “when” to harvest a cluster of grapes. Primarily it is the grape’s tannin, acid and sugar content that determines how ripe the grape actually is and they are key components for influencing a wine’s future finesse and strategic presence. Once hand picked, the grapes are transported to the winery. They are then crushed and their stems removed before fermentation is initiated.
Here at Monolithos Winery, we aim at getting the grapes to crush as early as possible on the day of harvest, so that the juice starts to flow as quickly as possible. Great pains are taken to escalate the process, whilst keeping the grapes from becoming too warm during the transport from vineyard to the crusher. For example, many grape varietals are cut from the vine in the cool, early morning hours to help to keep the grapes’ astringency to a minimum. Thanks to the support from the friends of Monolithos, we were always successful since harvesting is a group activity and one that involves dedication.
Harvest time is a beautiful season to visit Pachna; the vines are heavy with bunches of juicy grapes and multi-coloured leaves and there’s excitement in the air since this is the time that the villagers will be rewarded for a year’s work. Harvesting is a memorable experience that helps wine lovers to understand better the issues of quality in winemaking.
For a real “hands-on” experience of the grape harvest, you can pick grapes yourself! Monolithos winery invites all wine lovers to join us in the vineyards to help pick the grapes for this year’s vintage. All you need is to phone Miriam on 99-555242 to learn about the harvesting programme and register your interest. Whether you choose to witness the harvest firsthand or just discover it once the grapes are safely inside the bottle, it is truly the tangible culmination of a solid year’s worth of work, care and expertise.
If at any time you are passing near the village of Pachna and wish to visit the winery, participate in any of our functions or sample any of our products, Martin Wood will be pleased to meet and assist you at his “Fig Tree Villa” in Pachna, so do not hesitate to phone him at 25-816212 or 99-165995.
Regards from all of us here at Monolithos and always remember:
“Wisdom doesn’t automatically come with age. Nothing does - except wrinkles. It’s true that some wines improve with age – but only if the grapes were good in the first place.”
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