How to Understand Wine
How to Understand Wine: Enhancing Agents
Crushed-insect colourings and hot steel tiles: the weird and wonderful world of wine manipulation
Since the pre-Socratic era, winemakers have been adding fragrances and other additives to wine to improve its aesthetic appearance; to make it taste and smell better. The practice of drinking wine was vastly different, with the Ancient Greeks diluting wine with water in order to drink it. Wine was often seen as a way to improve the taste of water rather than a drink in its own right. Dioscorides Pedanius (40–90AD) added crocus oil, myrrh, frankincense and cinnamon, amongst others, and Homer mentions the addition of opium. Alkaloids were often added to alcohol as ethanol is a good alkaloid solvent and the two mix well. For much of history, it was believed that wine had medicinal properties, and it was sometimes used as a base medical solvent to which other healing herbs were added.
For much of history, mixed beverages were created which used many external ingredients, from herbs and spices to lead, blood and urine, to create different tastes. The most famous among these is the Ancient Greek retsina which used different tree barks to disguise the vinegar which formed in it during hot summers. However, as these were mixed fermented beverages they would not classify as wine under the 1907 Southern Wine Revolt act. Therefore, throughout this chapter we will instead focus on additives which seek to change the flavours of the wine whilst still keeping the vast majority of the wine consisting of grape juice.
Between 1600–1800, several methods of removing the smell of wine were pioneered — a hot steel tile placed inside the wine barrel for 24 hours was said to do the trick. Additionally, half-cooked bread dough placed inside the barrel also removed any off scents. Laurel seeds boiled in wine and added to the barrel would correct any sour taste. Flavours began to be added purely for taste in minute quantities — Charleton describes how linen bags full of crushed aromatics were added to casks for a few days before removal to infuse the wine with flavourings.
Artifical Colours
Artificial colourings were used in red wines, including hollyhocks and myrtle berries. Turnsole was infused into rags by unscrupulous vintners in C16th London, which were added to the wine to dye it red, although this had the unfortunate side effect of making the wine taste like a rag. Later, cochineal, a crushed South American insect, became fashionable, albeit expensive. Spaniards began to add lime to sacks containing grapes to bleach sherries, as English tastes in the C16th preferred a paler drink. Lamb’s blood was used to dye white wines. So-called ‘orange wines’, which are wines produced from white grapes with extended maceration and skin contact, were some of the first wines ever made in the Caucasus and were highly popular throughout medieval Europe — many Renaissance paintings show orange, not white, wine in revellers’ glasses.
In order to be able to add perfumes and taste additives in a systematic way to generate a great wine, scientists attempted to discover the constituent components which make up the scent of a wine. This began partly with distillation, but distillation was not advanced enough to be able to properly separate fractions with the degree of accuracy required.
Bouquet
There were several conflicting theories as to the nature of a wine bouquet which proliferated throughout the C19th. One of the earliest misconceived theories was proposed by the great Justus von Liebig (1803–1873). Liebig believed that wines with a high concentration of tartaric acid naturally had the most pronounced bouquets, a theory only fully laid to rest in the 1860s. After Liebig proposed his tartaric bouquet theory, he also played a part in the first time a complex component of wine was found separate from wine itself. This occurred in 1836, when Liebig and Théopile-Jules Pelouze (1807–1867) stumbled across a sample of oenanthic acid (C14H26O2) in a London pharmacy. Oenanthic acid is a dimer of enanthic/heptanoic acid, named with the oeno- prefix to denote its vinicultural connections, and forms an oily ester which is created during alcoholic fermentation.
Liebig postulated that oenanthic acid was the essential smell of a wine, which comes from the oil which thickens as the wine ages, resulting in a stronger scent and accounting for the pleasantness of fine, aged wines. This was to be the start of a new set of oil-based theories about the bouquet of wine. In 1844, a J. Fauré established that this oil came from the grape skins and was released during the crushing process, and that a special substance only found in great Médoc wines, oenanthine, allowed the aromas to become fully realised.
Edme-Jules Maumené (1818–1898) later wrote in 1858 that the smell of a wine was a collection of different scents, like the bouquet in a perfume, as opposed to a singular oil or acid. He took inspiration from the perfume merchants of the day, and maintained that just as with flowers grown for perfume, the quality of the soil and the agricultural techniques used when growing vines had a great impact on the overall wine bouquet. This was developed by Pasteur, who proposed that there were two main contributors to the bouquet of a wine: namely, scents originating from the growth of the grape then from an acquired bouquet dependent on any oxygen contact the wine has as it ages. Later, attempts were made at the extraction and identification of specific aldehydes through distillation.
Blends
As wine chemistry became better understood and winemakers started to grow many different kinds of grapes on their land, different qualities (tiered blends) began to be produced. Producers could feel safe in the knowledge that should their Chardonnay succumb to rot; their Pinot Gris might be somewhat protected and they could still produce a wine for that year. Grapes were not selected for taste but for their capacity to ripen with a high sugar content, allowing for the manufacture of a wine alcoholic enough to keep and for the farmer to sell.
First came so-called field blends during the C18th, which took a whole field of different grapes and crushed and co-fermented them together indiscriminately. Farmers would plant either “white” grapes or “black” grapes, often with no mention of the mix of varietals. The reason that the fields were often an interplanted mix of blends is that it is difficult to separate grape varietals in the field from each other unless one has a good deal of botanical knowledge. This mixture of varietals as well as the differences in ripeness between individual grapes adds depth to the wines. Vineyards full of field blends were also planted by settlers all throughout California, but uprooted during the Prohibition from 1920–33. Field blends began to be phased out as fermentation tanks became cheaper and more information on how to identify different varietals emerged. However, field blends still exist — the Gemischter Satz is a speciality of Vienna, and several Californian vineyards still employ the technique, claiming that it offers an alternative form of terroir.
Terroir
Terroir first originated as a concept in the medieval period in Burgundy. As the time, it had become commonplace for the repenting bourgeoisie to bequeath gifts of land onto the monastic community (primarily Cistercian) on their deathbeds. This was seen as a desperate act of repentence, in a final attempt to enter the Kingdom of Heaven upon passing. As these bequeathments became routine, the monastic community became savvier to the practice. They started to request specific parts of an estate, as they gradually realised that certain parts of a vineyard grew intrinsically tastier grapes than others. This gave us the idea of terroir that we accept today — that certain parts of a vineyard produce better quality grapes than others, caused by the intrinsic geology and weather of the vineyard. This led to the creation of different classes of crus, and helped to refine wine flavours into the classifications we now hold, resulting in the selection of not just specific grape varieties, but also specific plots of land when blending.
This evolution in plot selection came into full force in Bordeaux during the 1800s. Nowadays in Bordeaux, blending precise amounts of different plots and varietals post-fermentation and barrel maturation just before bottling is an exact science. Blending is at the heart of a Bordeaux wine, with 5 different grape varietals permitted under the Bordeaux AOC: Cabernet Sauvignon, Merlot, Cabernet Franc, Malbec and Petit Verdot.
In Burgundy, wine merchants practiced coupage — tr. ‘cutting’ — which is the adulteration of fine wine with poor quality juice in order to maximise the amount of fine wine the merchant had available to sell. Burgundy never embraced the blending process as enthusiastically as the Bordelaise, and nowadays mostly single varietal wines (Pinot Noir and Chardonnay) are created. André Jullien (1766–1832), one of the first dedicated wine writers, discussed in an 1822 work the necessity of blending wines in poor years to make them drinkable. However, in Burgundy this has never evolved into a search for a consistent taste and product in the way that it has in the Médoc.
