Riesling ( , ) is a white grape variety that is believed to have originated from the Rhine Valley region of western Germany, before later being traced to the Alsace region by 1470 and Austria by 1700Sechrist R. 2012. The Origin, Diffusion, and Globalization of Riesling. In The Geography of Wine: Regions, Terroir and Techniques. PH Dougherty (ed.), pp. 195–206. Springer Netherlands, Dordrecht.. Riesling is an aromatic grape variety displaying flowery, almost perfumed aromas as well as high acidity. It is used to make dry, semi-sweet, sweet, and sparkling white wines. Riesling wines are usually varietally pure and are seldom oaked. , Riesling was estimated to be the world's 20th most grown variety at (with an increasing trend),J. Robinson (ed) The Oxford Companion to Wine Third Edition, Oxford University Press 2006, p. 746: "Vine varieties", . but in terms of importance for quality wines, it is usually included in the "top three" white wine varieties together with Chardonnay and Sauvignon blanc. Riesling is a variety that is highly "terroir-expressive", meaning that the character of Riesling wines is greatly influenced by the wine's place of origin.
In cooler regions, such as the Mosel in Germany, Riesling wines often display apple and tree fruit notes with pronounced acidity that is sometimes balanced by residual sugar. As a late-ripening variety, Riesling can develop citrus and peach notes in warmer areas such as the Palatinate, Alsace, and parts of Austria. In Australia, Riesling is often noted for a characteristic lime note that tends to emerge in examples from the Clare Valley and Eden Valley in South Australia.
Riesling's naturally high acidity and pronounced fruit flavors give wines made from the grape good aging potential, with well-made vintages often developing smokey, honey notes, and aged German Rieslings, in particular, taking on a "petrol" character, as a result of the development of the compound TDN.Wine & Spirits Education Trust "Wine and Spirits: Understanding Wine Quality" pp. 6-9, Second Revised Edition (2012), London, .
In 2015, Riesling was the most grown variety in Germany with 23.0% and ,German Wine Institute: German Wine Statistics 2015-2016 . and in the French region of Alsace with 21.9% and .CIVA website , read on September 9, 2007. In Germany, the variety is particularly widely planted in the Palatinate, Rheinhessen, Mosel, Rheingau, Nahe, and Baden.
There are also significant plantings of Riesling in Austria, Slovenia, Serbia, Czech Republic, Slovakia, Luxembourg, northern Italy, Australia, New Zealand, Canada, South Africa, China, Crimea, and the United States (Washington, California, Michigan, and New York).
History
Riesling has a long history, and there are several written references to the variety dating from the 15th century, although with varying orthography.Freddy Price, Riesling Renaissance Mitchell Beazley 2004, pp. 16-18 . The earliest of these references dates from March 13, 1435, when the storage inventory of Count John IV of Katzenelnbogen in Rüsselsheim (close to the Rheingau) lists "22 ß umb seczreben Rießlingen in die wingarten" ("22 shillings for Riesling vine cuttings for the vineyard").http://www.graf-von-katzenelnbogen.de/ The History of the County of Katzenelnbogen and the First Riesling of the World.Winzerfreunde Rüsselsheim - facsimile and translation of the 1435 document .An earlier reference from 1402 in the city of Worms (Germany) that is sometimes quoted is not correct and based on a missinterpretation from the 1960s; see The spelling Rießlingen is repeated in many other documents of the time. The modern spelling Riesling was first documented in 1552 when it was mentioned in Hieronymus Bock's Latin herbal.Oz Clarke, The Encyclopedia of Grapes Websters International Publishers 2001, p. 192 .
A map of Kintzheim in Alsace from 1348 contains the text zu dem Russelinge, but it is not certain that this reference is to the grape variety. However, in 1477, Riesling was documented in Alsace under the spelling Rissling.Freddy Price, Riesling Renaissance Mitchell Beazley 2004, pp. 90-92 . In Wachau in Austria, there is a small stream and a small vineyard both called Ritzling, which are claimed locally to have given Riesling its name. However, there seems to be no documentary evidence to back this up, so this claim is not widely believed to be correct.Freddy Price, Riesling Renaissance Mitchell Beazley 2004, p. 118 .
Parentage Earlier, Riesling was sometimes claimed to have originated from wild vines of the Rhine region, without much support to back up that claim. More recently, DNA fingerprinting by Ferdinand Regner indicated that one parent of Riesling is Gouais blanc, known to the Germans as Weißer Heunisch, a variety that, while rare today, was widely grown by the French and German peasantry of the Middle Ages. The other parent is a cross between a wild vine and Traminer. It is presumed that the Riesling was born somewhere in the valley of the Rhine, since both Heunisch and Traminer have a long documented history in Germany, but with parents from either side of the Adriatic the cross could have happened anywhere on the way.
It has also been suggested, but not proved, that the red-skinned version of Riesling is the forerunner of the common, "white" Riesling.Wein-Plus Glossar: Roter Riesling , accessed on 13 January 2013. The genetic differences between white and red Riesling are minuscule, as is also the case between Pinot noir and Pinot gris.
Longevity
Riesling wines are often consumed when young, when they make a fruity and aromatic wine that may have aromas of green or other apples, grapefruit, peach, gooseberry, honey, rose blossom or cut green grass, and usually a crisp taste due to the high acidity.Owen Bird, Rheingold - The German Wine Renaissance, Arima Publishing 2005, p. 91 However, Riesling's naturally high acidity and range of flavours make it suitable for extended aging. International wine expert Michael Broadbent rates aged German Rieslings, some hundreds of years old, highly.Michael Broadbent, Vintage Wines Little, Brown 2002 pg 343 Sweet Riesling wines, such as German Trockenbeerenauslese, are especially suited for cellaring since the high sugar content provides for additional preservation. However, high-quality dry or off-dry Riesling wine is also known not just to have survived but also to have been enjoyable at an age exceeding 100 years. Jancis Robinson.com: Exploding myths about German wine.
The Ratskeller (council wine cellar) of the townhall of Bremen, Germany, stores 650+ German wines, including Riesling-based wines, often in barrel and back to the 1653 vintage.Michael Broadbent, Vintage Wines Little, Brown 2002 p. 344 .
More common aging periods for Riesling wines would be 5–15 years for dry, 10–20 years for semi-sweet and 10–30+ for sweet versions.Riesling Report issue #13 March/April 2002, pp. 8-13: The Rewards of Cellaring Riesling .
Petroleum notes in aged Riesling wines On release, certain Riesling wines reveal a striking petrol note (goût de pétrole in French) that is sometimes described with comparisons to kerosene, lubricant, or rubber. While an integral part of the aroma profile of mature Riesling and sought after by many experienced drinkers, it may be off-putting to those unaccustomed to it, and those who primarily seek the fruity aromas that typically characterize young Riesling wine. While petrol notes may be identified in Rieslings from any territory, they are most commonly found in aged Australian wines.Schüttler A, Friedel M, Jung R, Rauhut D, Darriet P. 2015. Characterizing aromatic typicality of Riesling wines: merging volatile compositional and sensory aspects. Food Research International 69:26–37. The negative attitude to petrol aromas in young Riesling, and the preference for fruitier young wines of this variety, seem more common in Germany than in Alsace or on the export market, and some German producers, especially the volume-oriented ones, have even gone so far as to consider the petrol notes a defect which they try to avoid, even at the cost of producing wines that are less suited to extended cellar aging. In that vein, the German Wine Institute has gone so far as to omit the mentioning of "petrol" as a possible aroma on their German-language Wine Aroma Wheel, which is supposed to be specially adapted to German wines, and despite the fact that professor Ann C. Noble had included petrol in her original version of the wheel.
The petrol note is considered to be caused by the compound 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN), which during the aging process is created from carotenoid precursors by acid hydrolysis. The initial concentration of precursors in the wine determines the wine's potential to develop TDN and petrol notes over time. From what is known of the production of carotenoids in grapes, factors that are likely to increase the TDN potential are: Ripe grapes, i.e., low yields and late harvest High sun exposure Water stress, which is most likely in regions which do not practice irrigation, and there primarily in certain dry vineyard sites in hot and dry years High acid content These factors are usually also considered to contribute to high-quality Riesling wines, so the petrol note is in fact more likely to develop in top wines than in simpler wines made from high-yielding vineyards, especially those from the New World, where irrigation is common.
Noble rot
The most expensive wines made from Riesling are late harvest dessert wines (often amongst the most expensive in the world), produced by letting the grapes hang on the vines well past normal picking time. Through evaporation caused by the fungus Botrytis cinerea ("noble rot") or by freezing and pressing (as is the case for ice wine – in German: Eiswein), water is removed and the resulting ultra concentrated juice is used to make the sweet wines. These wines are felt to offer richer layers on the palate, and have more sugar (in extreme cases hundreds of grams per litre), more acid (to give balance to the sugar), more flavour, and more complexity. These elements combine to make wines that are amongst the most long lived of all white wines. The beneficial use of "noble rot" in Riesling grapes was discovered in the late 18th century at Schloss Johannisberg. Permission from the Abbey of Fulda (which owned the vineyard) to start picking Riesling grapes arrived too late and the grapes had begun to rot; yet it turned out that the wine made from them was still of excellent quality.History of Schloss Johannisberg .
Noble rot is employed in many viticultural areas, including the Clare, Barossa, and Eden Valleys in South Australia, and in the southern growing region of Tasmania, though none are as renowned as those from Germany.
Production regions Riesling is considered one of the grape varieties that best expresses the terroir of the place where it is grown.Oz Clarke, The Encyclopedia of Grapes Websters International Publishers 2001, p. 194 . It is particularly well suited for slate and sandy clay soil.Jancis Robinson, Vines, Grapes and Wines Mitchell Beazley 2002 p. 105 .
Germany
Riesling is Germany's leading grape variety, with the country accounting for around 40% of global production. German Riesling is known for its characteristic “transparency” in flavour and presentation of terroir,Andrew Ellson, Roll out the riesling, German wines are making a comeback, in: The Times dated 9 December 2019.Wine Spectator Magazine, Wine in Northern Europe September 30th, 2006 p. 124. as well as its balance between fruit and mineral flavours. In Germany, Riesling typically ripens between late September and late November, with late harvest grapes sometimes picked as late as January.