WINE HISTORY
Wine History: Fermentation, Alchemy And Medicine
What did early man think of the magical process that transforms grapes into wine?
Fermentation is a funny thing in the wine, bread and beer world, causing extreme changes to ingredients with seemingly little input. As such, fermentation was — up until fairly recently — hailed as a semi-mystical process, and was widely revered in medicine and alchemy.
Early man was hypnotised by the fermentation that he observed when making wine, which originates from the Latin ‘fervere’. Translated, this means ‘to boil’, a comment on the bubbling liquid mass that forms as part of turning plain grapes into an alcoholic beverage. The heat given off during the fermentation also led itself to the misconception that the liquid is boiling off like water from a kettle.
Early Medicine
One of the great early physicians of our time was Galen, who lived in Ancient Greece between 129 and 210AD. He developed the theory of the four humors of Hippocratic medicine — black bile, yellow bile, phlegm and blood. The Ancient Greeks believed that these four substances were formed in the body, and different foods would lead to the production of one of the different humours through the process of digestions. Health was believed to lie in the perfect balance of all four, and Galen believed that digestion operated in the same way as grape fermentation in the liver.
This view of medicine was widely accepted for many centuries and did not undergo signficant change until the rise of the bubonic plague in medieval Europe. The plague inspired the Swiss alchemist Paracelsus (Theophrastus von Hohenheim, 1493–1541). Paracelsus attributed the spread of the disease to fermentation of the humors caused by illnesses in the air — as the illnesses in the air passed through the liver, they were allowed to ferment into the body. Paracelsus was also the first to use Galen’s term ‘fermentation’ in an alchemical context, and talked of “alcofol” (from the Arabic al-kuhul), which were fine powders or volatile liquids.
One hundred year later, Thomas Willis’1659 work Diatribae duae medico-philosophicae quarum prior agit de fermentation was published. This contunued to run with the misconception of fermentation as a mechanism to health and disease, ascribing fevers to the fermentation of the blood.
Fermentation & Alchemy
In the 16th century, Paracelsus founded the iatrochemical school, which sought to understand medicine and physiology in terms of chemistry. Paracelsus then coined the alchemical concept of the Archeus. The Archeus was a mystic agency which presides over the body and controls biological processes such as fermentations like digestion, which Paracelsus believed to be the highest form of alchemy. The Acheus was able to create the alkahest; an undiscovered universal solvent, and also able to create the philosopher’s stone. This led to an alchemical obsession with fermentation in a bid to create the philosopher’s stone. Samuel Norton (1548–1621), the great-grandson of Thomas Norton (1433–1513), the author of the Ordinall of Alchemy, wrote in 1577: “the stone…can never become Elixir, without it be commixed with the soule: which is the ferment”. In many alchemical texts, the Philosophers’ Stone is portrayed as a ferment — or a cluster of seeds of different metals which can be used to prepare various elixirs.
It wasn’t until the mid-seventeenth century that van Helmont (1577–1644) was able to cross fermentation over from alchemy and mysticism to enter the scientific vernacular. Despite having been a member of the iatrochemical school and crediting Paracelsus’ mystic Archeus with many biological processes, van Helmont was a rigorous scientist whose experiments could take years to complete. He, too, was inspired by the plague ravaging Europe to examine causes of disease and the mechanisms of the body. He believed that digestion, breathing and other biological processes were carried out by a ferment, which acted as a chemical reagent does today. It was his studies of fermentation and yeasts which led him to realize that burning charcoal and fermenting grapes led to the expulsion of the same gas which he called “gas sylvestre, or “wood gas” (CO2). This both coined the term “gas”, probably deriving from the German ‘geist’ (tr: ghost) and led him to postulate that air could exist in different states of compression, which gave it different characteristics.
Robert Boyle then took the concept of fermentation and applied it to his corpuscular school of thought, which re-imagined all previously-known biological processes in terms of small, discrete spheres. In 1661, Boyle published ‘The Sceptical Chymist’. One of the experiments in this work involved separating the fermentation (growth of a bacteria in a solution) from ferments (a bacteria). This was important as it enabled the corpuscular school to remove the mystical force Archeus from scientific thought, and enabled Boyle to begin to break free of the traditional Aristotelian elements (earth, air, fire, water), as well as Paracelsus’ three principles (sulfur, salt and mercury). However, Boyle himself was still an alchemist, a chymist in the old tradition – in 1689, he petitioned a law which could impede the creation of the philosopher’s stone, which lead a paranoid Isaac Newton to write in a letter to John Locke that he was worried that Boyle had found a way to create gold alchemically.
Spores
It was in 1680 that the ‘ferment’ in wine were first physically observed by van Leeuwenhoek, who found that they were yeast spores. van Leeuwenhoek is now widely considered to be the first microbiologist. After this observation, the true scientific study of yeasts – and by extension, fermentation – could begin. The biological study of the yeast cell would conclude in 1996, with the sequencing of the yeast genome which ultimately paved the way for the human genome project. In van Leeuwenhoek’s time, yeast was considered to be an inanimate paste which contained no living organisms.
Awareness of yeast as the catalyst for fermentation increased 18th century, with references appearing by Daniel Defoe in 1707, and two brief mentions in Tristram Shandy in 1760. And in the very first dictionary, written by Samuel Johnson’s in 1755, it was defined as “the ferment put into drink to make it work; and into bread, to lighten and swell it.” Yeast, then was seen more like a chemical catalyst than a biological agent as the scientific community continued to reject alchemical concepts such as the Archeus.
Yeast was used widely as a cure-all and to treat fevers throughout the C18th, and in 1781, the first attempt at creating an artificial yeast (to the knowledge of this author) was prepared by an English apothecary named Thomas Henry (1734–1816) by “impregnating flour and water with fixed air” – fixed air being the name at the time for CO2. By this time, the idea of gases comprising of different chemicals as well as different pressures was established. This was arguably the beginnings of the biological engineering of yeast.
Chemical Understanding
In 1789, Lavoisier published the first account of the changes which occur chemically during fermentation using yeast, and was able to describe the transformation of sugar into ethanol and gas. At that time, yeast was not recognised as a living organism. However, to Lavoisier’s credit, he was the first person that we know of to describe a chemical reaction by an equation. This also makes him the first person to postulate that the principle of the conservation of mass also applied in chemical reactions: “We have to assume that there is a true balance or equation between the elements of the compounds with which we start and those obtained at the end of the reaction”.
In 1815, Gay-Lussac revised the balance of Lavoisier’s equation, leading to the correct empirical equation for fermentation in the late C20th, which is still known as the Gay-Lussac equation today. Gay-Lussac was not the only scientist to continue Lavoisier’s work, and in 1858 Moritz Traube published Theorie der Fermentwirkungen, which was based on experimental evidence and finally suggested that fermentation itself was a living process. He was the first to define enzymes as protein-like compounds which need direct contact with the substrate to allow a reaction to occur. He suggested that enzymes act as catalysts to activate the reaction, which was widely rejected at the time, although it is now accepted as the primary mechanism for enzyme-controlled reactions.
So it took humanity at least 4,000 years to understand that yeast in fermentation is a living life form — giving some credence to that alchemical belief in the mystic Archeus after all.
Pasteur
Louis Pasteur was one of the first scientists to concentrate on the practicalities of everyday chemistry problems. In 1856, a local wine manufacturer asked Pasteur to investigate the problems he was having fermenting his beetroots into an alcoholic beverage. Pasteur happily jumped on the problem, and a year later published a memoir detailing his findings. He found that “air has always been considered the enemy of wine” and can inhibit alcoholic fermentation — this is still termed the Pasteur effect today. Pasteur also found that a by-product of the fermentation was lactic acid, which was the substance causing the farmer Bigot’s wines to sour. This made him “France’s greatest scientist”, and led to a meeting with Emperor Louis-Napoléon Bonaparte in 1862 which would result in the development of the pasteurization of milk and foods prone to spoilage.
Pasteur’s work on fermentation as a biological process also led to a long-running dispute with Justus von Liebig, a famous German biochemist who believed that it was instead a mechanical process resulting from vibrations from decomposing organic matter leading to the transformation of sugar into carbon dioxide and ethanol.
Pasteur also found that aeration inhibits alcoholic fermentation. This was developed by Eduard Buchner (1860–1917), who held that living yeast cells were not needed for fermentation. He showed that a liquid containing only yeast extract could ferment sugar, which was considered a great blow to the vitalist school at the time, which rejected bacteria in favour of vitalistic processes which carried out biological processes and caused fevers. The vitalists harked back to alchemical concepts of archeus and old alchemical ideas about fermentation. The discovery won Buchner the 1907 Nobel Prize in Chemistry. However, Buchner’s claim to priority is cast in some doubt by Maria Manasseina, who purported to discover the process 20 years before Buchner. Following Pasteur and Buchner, Georges Jacquemin published research and patents throughout the 1880s which developed the use of synthetic yeast strains.
So after all of that…it would seem that fermentation has been on a wild ride over the course of human knowledge, mostly misunderstood and blamed for processes far grander and more mystic than its simple and humble yeasty origins.
