Guest post by Rowena Fletcher-Wood

Was brandy first created as a tax dodge?

During the 15th and 16th century, alcoholic drinks were taxed by volume, since methods for assessing percentage of alcohol were relatively crude. This gave rise to a clever little corner-cutting idea: distil down wines for export, pay less tax, then add the water back in after delivery.

The process of distillation had been long known. It was usually performed in an alembic, or alchemists still apparatus, made of glass. Led by the Dutch, merchants started using these to boil down wine to between 35% and 60% abv, at which concentration they made an inferior-flavoured, very boozy concentrate.

Like all forms of preservation, the process left behind its own unique flavour, even after the concentrated drink was watered back down. The merchants accounted for this by calling the reconstituted wine brandewijn, or burnt wine to describe what they thought had happened to it. They might better have called it burning wine, for this was how they tested the concentrate – taking a portion and setting it alight, deeming the distillation adequate when their sample was entirely flammable . Often, several distillations were required, the first distillate being called the spirit of wine, and the improved distillate the spirit of wine rectified.

We know now that it is congeners – other molecules from the fruit or fermentation that are present in the drink – that produce the characteristic flavours in alcoholic drinks. These include esters and aldehydes, acids, oils, and small amounts of minerals and other solids – a playground of chemical complexity. The esters are highly volatile and contribute much of the aroma. Acids often contribute the bulk of congeners, but are not necessarily the dominant flavours: we pick up different chemicals at very different thresholds, so that, for example, the cis and trans isomers of oak lactones are perceived at very different concentrations. Most wines are very different from each other, and may only have a few congeners in common.

However, it’s not just the loss of volatile compounds that leads to the strange flavour of distilled wine, but also the decomposition of some congeners under heating. New volatile compounds are created in chemical reactions between contents and with the distillation vessel, such as the hydrolysis of esters.

During modern distillation processes in copper stills, brandy is made from a base wine that contains fewer sulfites which can react to make unpleasant copper sulfate. The distillate is collected in three steps, first the ‘heads’, then the ‘heart’, then the ‘tails’. The head contains highly volatile compounds, such as methanol, butane and hydrazine, many of which are harmful in high concentrations. The tail is filled with gritty solids that sediment at the bottom of the still. By keeping just the heart, distillers minimise the concentrations of harmful portions. Often, the head and the tails are distilled again and again, until every part that could come out as the heart has been extracted.

But distilled wine is not yet brandy. To make brandy, the distilled wine needs to be aged in wooden casks, such as on a long sea voyage – something the medieval merchants had failed to account for. When they tasted the brandewijn at the end of their travels, many of them were amazed to observe that the alcoholic burn had been softened, and new, smooth flavours introduced during maturation. The resulting liquid was also darker in colour. This was the accidental discovery of brandy.

Ageing is a complex and unique chemical process that takes place best in wooden barrels, such as those the merchants had designed for easy transportation.

The constitution of the distillate does not remain constant, with come congeners remaining stable while others degrade. The rate of degradation may vary, but eventually everything will be decomposed (probably, say the experts, who use sine wave mathematics on this kind of thing, after 15 years – so older brandies are unlikely to be any way improved).

Although compounds in the distilled wine can react together, most of the character of brandy comes from gradual oxidation through the porous wood, or reactions with the wood itself.

Oxidation reactions are affected by climate. In hotter places, evaporation is more rapid, and fast aging produces harsher brandies. Humidity affects the balance between ethanol and water evaporation. More water evaporates if it’s dry, and more ethanol if it’s humid, making up what distillers call ‘the angels’ share’. Since different compounds are dissolved in the water and ethanol fractions, the evaporation rate affects the flavour. Water houses rich sugars and colourants, whilst ethanol holds the aromatic derivatives from wood: lignins, vanillins and tannins.

Wood derivative flavours are also affected by pre-treatment, such as exposure to other alcoholic beverages, or charring, which was traditionally used to soften the wood for bending into barrels. Charring incidentally breaks down some lignins and tannins in the wood, and caramalises hemi-cellulose plant sugars.

Numerous scientists have explored the flavour and colorant molecules in brandy using techniques such as chromatography, UV absorption and mass spectroscopy. However, in the everlasting trend of corner-cutting, today many brandies are coloured to imitate aging, as storing the spirit for years, with the angels constantly taking their share, is expensive. There is even such a thing as counterfeit brandy. Therefore, some of these techniques are used to test for the characteristic spectra of compounds including sinapaldehyde, syringaldehyde, and coniferyl aldehyde that appear in real brandy, but not its imitation.

So while brandy itself came about as a means to reduce costs, in the modern drink we rely on chemists to sniff out the counterfeits and cut corners.

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Guest post by Rowena Fletcher-Wood

How do you create something? A picture, say, a performance, or a piece of writing?

You start with an idea, a shadow of the final opus, and you experiment, practice; you throw something down onto the paper and push the colours about until new words or shapes emerge from the writhing medley. Structures or sentences that may not be what you had imagined in the first place at all. And there, you have discovered something. Or created something. Where does discovery really begin and creation end?

Poring through over 100,000 medical recipes in ancient Chinese literature, researchers came across a tale of discovery – but this was no ordinary discovery. Shrouded in mystery, and written in even more mysterious prose; tangled, poetic, using words that turn away from their ancient meanings to become a new and powerful metaphor – this was the language of the alchemists. And the tale, told and retold, recoloured and refashioned, full of sparks and glints, already several centuries later than the events it describes, is the tale of flickering fire, the tale of how earth becomes light, a tale of metaphor. And there it is, pinyin, the fire medicine. (more…)

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Chemistry World was delighted to sponsor a poster prize at ISACS19 (Challenges in organic chemistry), held in Irvine, US, last month. Aubert Ribaucourt, a postgraduate researcher at the University of Oxford, UK, won the prize with his poster entitled ‘Total synthesis and structural revision of aruncin B.’

Aubert Ribaucourt

Aubert explains his work:

‘My doctoral research is focused on synthesising anticancer natural compounds, specifically inhibitors of anti-apoptic proteins; these proteins are present in every human cell but are often over expressed in tumoral cells, especially in the case of drug resistant cancers. (more…)

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Guest post by Rowena Fletcher-Wood

When I am an old woman I shall wear purple

– Jenny Joseph

Colour is a powerful thing. It communicates emotions, beauty and status, unleashes our creativity and draws our attention. Wearing purple may have seemed slightly eccentric to poet Jenny Joseph, but in ancient Rome, it was the colour of power – and no surprise: their Tyrian purple was not only a lasting dye that seemed to become more rather than less vibrant under the sun, but it reportably took as many as 12,000 snails to produce enough dye to colour the trim of a toga!1

Purple clothing – ©iStock

Up until the mid 19th century, all dyes were naturally produced – from minerals (yellow ochre), plants (indigo and turmeric), or animals (cochineal and Tyrian purple). Of course, some of these natural dyes had their problems. Making Tyrian purple required thousands of snails and a laborious process, other colours were inclined to fade or run, and some even broke down the fabrics they were used to colour.

Despite all of this, synthetic alternatives were not sought at the time: organic chemistry was not sufficiently understood to guess at a link between structure and properties, and in fact, by the mid 1800s, chemistry was still very much a private practice.

One chemical practitioner was August Wilhelm von Hofmann of the Royal Society. Hofmann was interested in quinine, an extract from the bark of the cinchona tree used to treat malaria. In the mid 1800s, he published a hypothesis for the synthetic production of quinine, and set one of his students the challenge of producing it. (more…)

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Guest post by Rowena Fletcher-Wood

How do you feel about Botox?

To some, it’s a routine fix, a gift in the battle for eternal youth, found at the tip of a needle. Others, perhaps understandably, feel rather uncomfortable at the thought of injecting their face with a potent neurotoxin, just 50 grammes of which could wipe out all human life.

A man recieving botox treatment – © Shutterstock

But how would you feel to hear that Botox was discovered by accident – that this potent neurotoxin, which acts by paralysing muscles into flaccidity, was at some point injected into somebody without knowing everything it would do? In a marriage between cosmetics and surgery, this is how Botox came about.

Of course, people have been looking for something like Botox – and for a long time too. Back in the 16th century, women would stir up a white paste of vinegar and lead and plaster it across their faces in the same vein as foundation today. Once the mask had set, they would be unable to make any facial expressions at all for fear of cracking it, but apparently it was still worth it, despite the massive doses of lead that would have been slowly poisoning them, and the rancid unpleasant smell of the vinegar. Slightly less bizarre (but bizarre all the same) was the later introduction of uncooked egg white glaze to the same result. This at least didn’t poison anybody, assuming the eggs were healthy.

Then, in the 1820s, there came ‘wurstgift’. This was not a cosmetic face paint, but the first discovery of botulinum, found by German scientist (and apparent masochist) Dr Justinus Kerner, who isolated it from sausages that were past their best. He was investigating the deaths of several Germans at the hands of blood sausages, and his analysis of the toxin included going as far as injecting it into himself to observe its effects. Dr Kerner was, in fact, the first recipient of botulinum toxin, or Botox. (more…)

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Another year means only one thing, another chance for some epic chemistry doodles to deface the front of our favourite reading material. So far, the first few months of the year have certainly not disappointed.

The Royal Society of Chemistry has made a strong start to the year; in Chemical Society Reviews some smart art quite literally added to the chemical toolbox, whilst another elemental superhero smashed the main group of the periodic table in a focussed special edition from February. Over at Chem. Comm. I spotted a delightful entry using a stained glass window to demonstrate MOFs forming ‘holey glass’.

Across the sea at Wiley, Angewandte Chemie continues to stack up the comical pictures in their ever growing art gallery. Every week they put out not just one, but four front covers! Because as we all know a magazine obviously has four fronts, including the front front, the inside front, the back to front, the inside out and probably some others. Angewandte also produces a frontispiece, which serves as yet another cover for a featured article. A particularly forceful recent entry announced the latest episode in the benzene chemistry saga as the Cubane Awakens.

One of my favourite covers from the start of this year, however, is from Green Chemistry where it appears that a new set of emoticons have taken over. (more…)

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Guest post by Rowena Fletcher-Wood

Witches, everybody knows, don’t like to be messed with. Mess with them, and they’ll point their horribly gruelled finger at you and intimate that you will be next.

And no time nor place we know of now was worse than the Salem witch trials of 1762. Fingers were pointed all over the place, and the rope swung on the gallows. It lasted for a season, a miserable spring, and then it ended, but it was not forgotten.

Ergot infested rye – © Shutterstock

In 1976, Linnda Caporael published a paper that pointed the finger for witchcraft in a different direction – into the fields. They mostly contain rye in that part of Massachusetts, and it had been a warm, damp growing season, the kind that breeds moulds and fungus. Caporael indicated one fungus in particular: ergot, an alkaloid-loaded parasite.

At the time, the dark, fusiform fingers that protrude from the rye ears like they’re giving one-up to the heavens were thought to be simply sun-baked kernels, harmless. But this was far from the case, and in 1853 ‘ergotism’ was discovered, a long term cumulative poisoning from eating ergot.

Although they knew nothing of ergotism in Salem, it is possible that the accusers suffered from it. (more…)

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Guest post by Heather Cassell

Over the course of your life in the lab you can get to learn many different experimental techniques, and for most people this can be both very interesting and very exciting – the intrigue of novelty. But you can also get stuck using just a few techniques over and over, which can be frustrating and reduces the excitement to drudgery. Sometimes repetition is necessary if your experiment doesn’t go so well, if the process needs optimising, or if you have many similar samples to process in the same way. If the repetition is simply due to a large number of samples then perseverance is required to get the results you need. If the quality of your science depends on a little drudgery, then that’s what it takes.

Groundhog in Minneapolis – Image by Marumari at the English language Wikipedia, CC-BY-SA-3.0 or GFDL

But if there are problems with the experiment itself, a good place to start is repeating the experiment without change, to eliminate the possibility that something was set up incorrectly. (more…)

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What should we name the new elements? Chris Chapman, Chemistry World‘s comment editor, puts forward the case for his favourite…

The news that we have four new elements is, obviously, buttock-clenchingly exciting for chemistry name nerds. The four new confirmed elements – 113, 115, 117 and 118 – will now have a proper name instead of the tongue-twisting ununpentium and the like. This can be proposed by the discoverers, although the International Union of Pure and Applied Chemistry (Iupac) will get the final say. According to its latest rules, currently out for consultation, the elements can be named after a mythological concept or character; a mineral; a place; a property of the element; or a scientist. The endings of the elements are already decided: 113 and 115 will end in ‘ium’, 117 ‘ine’, and 118 ‘on’.

© Everett Collection/REX Shutterstock

Captain America – © Everett Collection/REX Shutterstock

So here’s a suggestion to the Japanese Riken group (discoverers for 113) or the Russian-American collaboration who discovered 115. How about vibranium?

Vibranium, as any comic book nerd knows, is a key element that comprises Captain America’s shield, and gives the irritatingly squeaky clean hero a way to dink bullets away, or a handy Frisbee to take out some bothersome villains. It’s also the element that Tony Stark ‘invents’ in the abysmal Iron Man 2 to end his crippling palladium dependency. Bizarrely, in the movie in turns out the element’s structure was hidden by his father (John Slattery, playing exactly the same character as he did in Mad Men) in a diorama of a 1974 business expo. Tony proceeds to go on a drinking binge, hurl abuse at Don Cheadle and miraculously create the element at his Malibu pad with little more than his raw genius. (more…)

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Guest post by Rowena Fletcher-Wood

When the Children of the Nineties survey discovered that a good number of mothers were feeding their babies cola, the public were shocked. But, believe it or not, Coca-Cola was originally developed as a healthy medicine. Its inventor was John Stith Pemberton, a pharmacist by trade, whose aim was to develop new ‘brain tonics’.

He also had personal motivations. After receiving pain relief treatment as an injured soldier in 1865, Pemberton had become addicted to morphine. This was not an uncommon problem amongst war veterans, but as a pharmacist, Pemberton was especially aware of the dangers of his addiction. He tried many mixtures in the hopes of developing an opium-free alternative, including his amusingly-named, if unprofitable, ‘Dr Tuggle’s Compound Syrup of Globe Flower’. (more…)

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