How Coffee Is Decaffeinated

Doctor Poison might have risen to Goethe’s challenge and discovered caffeine, but the solution to the playwright’s sleep problem was almost a century away and was discovered by accident. Caffeine, a white, bitter-tasting powder in its pure state, is soluble and can be extracted by waterlogging a green, unroasted coffee bean. When German coffee merchant, Ludwig Roselius, took delivery of a shipment of coffee beans in 1903 that had been soaked, he was loathe to throw it away. Instead, after processing some of the beans, he found that the drink tasted and smelt like coffee, just minus the caffeine which the seawater had washed out.

Replacing seawater with benzene, a chemical that, at the time, was used in paint strippers and aftershave, Roselius developed a process for decaffeinating coffee beans which enabled his company, Kafee HAG, to become the first, in 1905, to offer instant decaf coffee on a commercialised basis. Benzene, though, is a known carcinogen and nowadays coffee merchants, who use a chemical-based method to extract caffeine, deploy either methylene chloride, itself toxic if humans are exposed to high quantities, or ethyl acetate.

The green coffee beans are either soaked in hot water and then washed in a chemical solution (the indirect-solvent process) or steamed for about thirty minutes, then washed in the chemical solvent before being steamed again to remove any solvent traces (the direct-solvent process). Purists claim that exposing the beans to hot water, either directly or as steam, damages their natural oils and flavours before the start of the extraction process.

More recently two non-solvent-based methods for extracting caffeine have been developed, the earliest of which to be used commercially, the Sparkling Water method, was also discovered by accident. In 1967 Kurt Zosel, a chemist at the Max Planck Institute for Coal Research in the Ruhr, was working with carbon dioxide and discovered that when the gas is heated and put under pressure, it can be used for separating different chemical substances.

The beans are gently moistened which causes them to expand and widen their pores, giving the more mobile caffeine molecules more room in which to move. They are then washed over with a natural carbon dioxide solution which eases out the caffeine, a process which produce little waste, is completely chemical-free, and does not damage the flavour of the coffee.

Alternatively, the Swiss Water Process, developed in Switzerland in 1933 but not used commercially until 1979 by Coffex S A, uses a heated proprietary Green Coffee Extract (GCE) which contains all the water-soluble compounds found in coffee, except caffeine. The green beans are soaked in it, causing them to swell, expelling the caffeine molecules into the GCE while retaining the more volatile taste and smell compounds. This process can take between eight to ten hours before all the caffeine is removed. While the GCE can be reused for the next batch, critics point out that by doing so the unique qualities of a particular batch of beans can be compromised.

Decaf coffee beans look different from their caffeinated confrères, shinier and darker in colour, a consequence, Andy Cross of Two Chimps Coffee[1] explains, of their drying process, during which, while heated, they rub against and polish each other, creating their characteristic sheen. However, the colour adds to the roaster’s difficulty in judging when they are ready as does their reduced bound water content which accelerates the speed at which they roast. Nonetheless, if decaffeinated well and in the hands of a skilled roaster, decaf coffee will taste just as delicious as regular coffee.   I wonder what Goethe and Doctor Poison would have made of it all.


Device Of The Week (5)

Good news for hot dogs (and cats). Until it starts raining cats and dogs again, if it ever does, one problem facing pet owners is how to keep their furry friends cool. A Tokyo-based maternity wear manufacturer, Sweet Mommy, has teamed up with some veterinarians to come up with a pawsible solution.

Retailing at 9,900 yen (around £60) and the brainchild of company president, Rei Uzawa, it is an eighty-gram, battery operated fan that is attached to a mesh outfit and blows cool air around the animal’s body.    

It is such a simple idea that it is a wonder that it has not been thought of before. Japanese pet owners are hounding the company in a desperate attempt to get their hands on one. Whether it will find its way to these shores before we are bemoaning the cold weather, only time will tell.

Sporting Event Of The Week (31)

England’s women might have won the Euro championships, but Scotland has just crowned its first national tree-hugging champion. The Inaugural Scottish Hugging Championship was held on July 22nd at Ardtornish as part of the Morvern Games and Gala Week. Organised by Darach Social Croft and An Darach Forest Therapy, the competition attracted twenty-four competitors, double the number the organisers had anticipated.

There were three events on the programme; speed hugging, where competitors had to hug as many trees in a specified area in a minute, with each hug lasting a minimum of five seconds, dedication, where participants had to hug a tree for up to a minute in a way that showed presence, intention, love, and respect, and freestyle, where entrants were required to demonstrate the most inventive way to hug a tree, again for no more than a minute.

The winner was Alasdair Firth, who was dressed appropriately in a leaf-covered camouflage suit and lives in a woodland croft in Rhemore on the Morvern peninsula.

The event was held in association with the World Tree Hugging Championships held annually in the HaliPuu Forest in Levi, in Finland. This year’s championship will be held on August 20th and is one I shall follow closely.

To watch the Scottish event, clink the link below  

Thirty-Eight Of The Gang

According to James Ware in his Passing English of a Victorian Era, there were compensations to be had from a spell of wet weather. Pavement were rudimentary and soon turned into a sea of mud, heralding the arrival of Shulleg Day. To prevent their long dresses from dragging in the mud, women would hitch them up, revealing a glimpse of ankle and lower leg to onlookers. Shulleg is a mangling of show-leg.

We know what a sit-down supper is, but what is fascinating was why it was necessary to emphasis that a meal would be taken sitting at a table. Apparently, in the late 1850s the medical press began to agitate against the practice of ostentatious and expensive banquets. The result was a more economical approach to feeding an assembled crowd, by inventing the stand-up meal, which by necessity was a thinner meal than a banquet. Old-fashioned people, Ware wryly observes, adopted this term to emphasis the difference.

Looking for an inventive way to describe an impossibility? Try six buses through Temple Bar, a phrase attributed to the MP, General George Thompson, who represented Tower Hamlets from 1847 and was a prominent abolitionist. John Bright, speaking in Leeds on October 18, 1883, gave some colour to the phrase when speaking against the proposed Suffrage Bill. He said that those proposing it “will be committing that great mistake which our old friend General Thompson used to describe as being made by the man who insisted on driving six omnibuses abreast through Temple Bar”. They just would not fit!

Barra Atlantic Gin

Barra, the second southernmost inhabited island of the Outer Hebrides, is known as the “Garden of the Hebrides”, home to an abundance of flora and fauna including over a thousand species of wildflower. It is also now home to Isle of Barra Distillers who produce Barra Atlantic Gin, but when Michael and Katie Morrison launched it in August 2017, it caused a bit of a stushie. The problem was that it was not only contract distilled but the distillers that the husband-and-wife team had chosen to use, Thames Distillers, were based in London. The prospect of a gin masquerading with a Scottish name but produced south of Hadrian’s Wall was too much for some to bear.

Happily, the Morrisons received their full distiller’s licence in May 2019 and were able to move the production of their spirit to the island where it is distilled, bottled, and labelled. Having overcome that obstacle, they now have ambitions to distil their own whisky on the island that was made famous as the location for the 1949 film adaptation of Compton Mackenzie’s comedy classic, Whisky Galore! To help bring their dreams to fruition by part-funding the enterprise, they have established a Membership Club which, as well as giving first dibs on their whisky, also offers other benefits such as the opportunity to secure a bottle of their Gold Cave Cask-aged Gin, a limited edition of 501 bottles. Ambitions galore!

Cementing their association with the island, the Morrisons have chosen to use as their signature botanical Carrageen seaweed. A red alga which they hand-forage from the shoreline, it is a particular favourite with the islanders who use it to make a seaweed pudding, his grandmother’s proving the inspiration for Michael’s use of it in the gin, as a broth and a form of blancmange.

As well as Carrageen, there are sixteen other botanicals used, which include liquorice, lemon peel, juniper, angelica root, orris root powder, mint, Quebec peppers, lemon balm, elderflower, dried peppermint, coriander, orange peel, cassia bark, chamomile flowers and, intriguingly, two mystery botanicals. Apparently, a lucky night at the roulette wheel on number seventeen convinced the Morrisons that seventeen was their lucky number, but I would hope, charming as the story is, there is a bit more science behind their calibration of botanicals.

The bottle is elegant, perfectly cylindrical with a broad shoulder and a medium-sized neck leading to a wooden stopper with an artificial cork. The label, designed by Devon artist, Jemma Lewis, has a floral, rockpool look and marbled effect, caused by the addition of Carrageen to the paint which causes the oils to rise. It uses a dark blue background and white lettering to optimal effect, informing me that it is “Island born, fearless spirit” and that their inspiration comes from the adventurous spirit of the Barra people.

The gin itself does not disappoint. Drinking it is an experience rather akin to standing on the coastline, mouth agape, watching the waves roll in. This complex spirit ebbs and flows between sweet and spicy, underpinned by a slightly oily juniper before finishing with zesty citrus and a mild saline taste from the Carrageen on the lips. Working well a mixer, Atlantic Gin is impressive, delicate, and seductive, belying its 46% ABV strength.

After a stormy beginning, the squall clouds have lifted for Isle of Barra Distillers. I hope their other plans meet with the success they deserve.

Until the next time, cheers!

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