Caffeine. Alcohol. Nicotine. These are the three most widely-consumed drugs in the world. Every day, around 80% of the world’s population – around 6.4 billion people – consumes caffeine – typically in the form of coffee, tea, or cola – with the average consumer’s daily intake being around 200 milligrams. Meanwhile, 32.5% of the world’s population – around 2.4 billion people – consume alcohol – mainly in the form of wine and beer – with an average daily consumption of 1.2 standard drinks or 17 grams of pure ethanol. However, for various reasons including health concerns, religious prohibitions, or simple personal preference, many people are unable to enjoy an energizing cup of Joe in the morning or a cold, relaxing brew at the end of the day. Thankfully for those who still wish to enjoy the taste of these drinks without any of the negative effects, a wide variety of options are available, including decaffeinated coffees and teas and non-alcoholic wines and beers – many of which are virtually indistinguishable from their more psychoactive counterparts. But how are these remarkable beverages produced? How do manufacturers remove one of their most fundamental components while leaving the taste largely unchanged? Well, pour yourself a hot – or cold – one as we dive into the fascinating history and chemistry of caffeine and alcohol-free drinks.

We begin our story with the decaffeination of coffee and tea. The first person to extract caffeine from coffee beans was German chemist Friedlieb Ferdinand Runge, who in 1819 isolated the active ingredient of the deadly nightshade plant Atropa belladonna – a toxic alkaloid today known as atropine. During the Renaissance, women dripped extract of deadly night shade into their eyes to dilate their pupils and achieve a fashionable doe-eyed look – hence the name belladonna, meaning “beautiful woman.” Runge determined that atropine was responsible for this dilating effect, testing the compound on the eyes of cats. This research soon came to the attention of German poet and polymath Wolfgang von Goethe, who, having just received a shipment of coffee beans, asked Runge if he could isolate the active stimulant compound. Runge obliged, and in 1820 succeeded in extracting and identifying caffeine. However, this is where his research on the matter ended; he did not further investigate the chemistry of caffeine nor seek to use his extraction process commercially to produce decaffeinated coffee. That breakthrough would have to wait nearly a century.

The father of decaffeinated coffee as we know it today was Ludwig Roselius, a coffee roaster’s apprentice from Bremen, Germany. Roselius’s quest against caffeine was a personal one: his father’s death in 1902 was attributed by the attending doctor to his drinking too much coffee. However, the method for removing it from coffee was discovered entirely by accident. As the story goes, one day Roselius received a shipment of coffee beans which had accidentally been soaked in seawater. After drying, roasting, brewing, and tasting the beans, Roselius found to his surprise that the saltwater had removed most of the caffeine while leaving the flavour largely intact aside from a slight saltiness. Based on this discovery, in 1905 Roselius patented a decaffeination method and in 1906 founded the company Kaffee Handels-Aktiengesellschaft or Coffee Public Trading Company – better known as Kaffee HAG. Roselius’s decaffeinated coffee beans would soon be sold across Europe under the brand name Sanka – a contraction of the French sans caféine – and in the United States as Dekafa.

Kaffee HAG’s process, known as the direct organic solvent method or Roselius method, involved steaming green, un-roasted coffee beans with ammonia-laced water until they became saturated with water and swelled to double their original size. The beans were then washed with an organic solvent like benzene or chloroform, which dissolved and flushed out the caffeine. Finally, the now-decaffeinated beans were dried and packaged for shipment to roasters and distributers. Later, Kaffee HAG developed a different decaffeination process known as the indirect solvent method. In this process, the green beans were soaked in hot water to effectively produce a raw coffee containing both caffeine and other flavour molecules. This fluid was then moved to another area and treated with organic solvents to remove the caffeine, before being returned to the beans. This process was repeated several times until all the caffeine was leached out of the beans, whereupon the beans and raw coffee were dried together, producing beans containing all their original flavour molecules except caffeine.

Kaffee HAG proved an instant success, with its innovative product, advertised as beneficial for the heart and nerves, meshing well with the various health and natural food movements of the 1910s and 20s. However, the company received a particular boost in the 1930s from an unexpected source: the Nazis. As part of their Lebensreform or “life reform” movement – intended to preserve the health and vitality of the Aryan Race, the Nazis promoted a more natural, “clean” lifestyle that eschewed supposed “poisons” like refined sugar, alcohol, tobacco, meat, and caffeine. Nazi propaganda railed against the dangers of caffeine, creating the perfect environment for Kaffee HAG to promote its products. At the 1937 Reichsausstellung Schaffendes Volk, a festival celebrating the accomplishments of the German people, over a dozen cantinas served Kaffee HAG decaffeinated coffee; while at the 1936 Nuremberg Rally the company supplied Kaba, a chocolate milk drink, to over 42,000 members of the Hitler Youth. The irony, of course, is that while the Nazis were decrying caffeine as poison, German soldiers and even many civilians were being actively supplied with Pervitin – a form methamphetamine – in order to ward off fatigue and boost performance both on and off the battlefield. Furthermore, Roselius’s decaffeination process left behind traces of benzene which, as a known carcinogen, was likely more dangerous to drinkers’ health than caffeine. For this reason, the modern direct decaffeination process uses safer solvents such as dichloromethane or ethyl acetate.

And despite his steadfast support of Hitler and his many attempts to join the Nazi party, Ludwig Roselius was never accepted as a party member for a number of reasons. For example, in 1932 – just prior to the Nazis’ rise to power – Kaffee HAG advertised its coffee as being Kosher and stated that:

“Anyone who drinks Kaffee HAG is dear and important to us. Which political affiliation or creed he is, is for us completely irrelevant.”

Furthermore, Roselius was a Freemason, supported various artists known to be members of the Communist Party, and patronized architectural projects frowned upon by the Nazi party. And while Third Reich health policies certainly played a large role in Sanka’s success in Germany, some historians have pointed out that similar Nazi campaigns against tobacco and alcohol were largely unsuccessful. Sanka’s appeal, they argue, lay more in its status as a luxury product, costing three times as much as regular coffee.

Nor did Kaffee HAG’s affiliation with the Nazis affect its popularity elsewhere. Indeed, Sanka is still sold around the world to this day, being a subsidiary brand of the Kraft Heinz multinational food corporation. Interestingly, in addition to being the first successful brand of decaf coffee, Sanka played another, influential role in modern coffee culture. To help its product stand out, Kaffee HAG sold Sanka in glass jars with distinctive bright-orange labels. During the First World War, the American subsidiary of Kaffee HAG was confiscated by the Office of Alien Property Custodian and turned into an independent American company, which in 1932 was purchased by General Foods. To help promote its new product, General Foods distributed coffee pots to cafes and restaurants across the country with handles or lids painted bright orange. This practice made it so easy for waitstaff to distinguish between regular and decaf coffee and became so ubiquitous that to this day orange coffee pots are universally associated with all decaf coffee – not just Sanka. And for more on another popular beverage that originated in the Third Reich, please check out our previous video How World War II Created One of the World’s Most Popular Soft Drinks.

In 1933, just as Ludwig Roselius and Kaffee HAG were starting to cosy up to the Nazi Party, a new decaffeination process known as the Swiss Water Method was developed which did not use any toxic organic solvents – only water. Originally invented by the Swiss Coffee S.A. company, the process was not truly perfected for another 5 decades, being finally introduced to the market in 1988 by the Swiss Water Decaffeinated Coffee Company of Burnaby, British Columbia, Canada. The Swiss Water Process is based around a substance called green coffee extract or GCE, produced by soaking green coffee beans in hot water and passing the resulting raw coffee through a series of activated charcoal filters to scrub out the caffeine molecules. The decaffeination process begins by soaking green coffee beans in GCE. As the GCE is hypotonic or deficient in caffeine compared to the beans, caffeine will leach out of the beans into the GCE. However, as the concentration of other compounds in the GCE is identical to that in the beans, those components stay put. Once equilibrium has been reached, the GCE is drained away, scrubbed of caffeine, and the process repeated. The Swiss Water Process takes around 8-10 hours start-to-finish and can remove 99.9% of the caffeine from coffee beans without the use of chemicals while preserving the beans’ original flavour profile. Coffee decaffeinated via this process is thus often marketed as more “natural”, “organic”, and “healthy” than other brands. However, because water is used in the early stages of the process, coffee decaffeinated using the indirect organic solvent method is also often marketed as “water-processed” – so buyer beware!

The fourth common method used to decaffeinate coffee – and tea, by the way – is perhaps the most exotic: the supercritical carbon dioxide method. As we all learned in elementary school, matter can exist in three basic forms: solid, liquid, and gas (and yes, I hear all you pedants screaming: also plasma – but that is outside the scope of this discussion). Which of these states a particular substance exists in depends on two factors: pressure and temperature. For example, at low temperatures and pressures, Carbon Dioxide is a gas. At low temperatures and high pressures it is a liquid, while at even lower temperatures and higher pressures it is a solid – what we typically call dry ice. However, above 304.128 Kelvin and 7.3773 Megapascals – what is known as the critical point – Carbon Dioxide undergoes a strange transformation, attaining a state halfway between a liquid and a gas. This phase, known as supercritical carbon dioxide, is an excellent and versatile solvent, and widely used in industry for countless tasks including dry cleaning clothing, extracting essential oils and other plant compounds, cleaning pesticides from grain and other crops – and extracting caffeine from coffee beans and tea. Compared to regular organic solvents, supercritical carbon dioxide does less damage to extracted compounds, evaporates completely when its pressure is increased, and leaves behind no toxic residues. And while it is more expensive than other methods, it can more quickly process large volumes of coffee beans. Furthermore, it more efficiently extracts pure caffeine as a byproduct, which can then be sold for inclusion in caffeine pills, cold medications, energy drinks, and other products – and for more on another state of matter that seemingly defies logic, please check out our previous video The Weirdest Substance Known to Science.

But whatever process is used, today decaf coffee makes up around 12% of total global coffee consumption – a number that is steadily growing year by year. However, it is important to not that while coffee and tea treated with the aforementioned processes are marketed as “decaffeinated”, they are not, in fact, entirely caffeine-free. Indeed, according to FDA regulations, coffee is considered decaffeinated when at least 97% of its original caffeine content has been removed. Beyond this, the actual caffeine content will vary significantly from brand-to-brand. So if you are someone whose body is sensitive to even small amounts of caffeine, it is probably best to avoid decaffeinated coffee or tea altogether and stick to herbal tea, hot chocolate, and other alternatives. Or you may want to try out one of the newest entries in the field of decaffeinated beverages: naturally caffeine-free coffee. Coffeea charrieriana, also known as Charrier Coffee, is a member of the Coffea genus native to Cameroon in Central Africa whose beans naturally contain no caffeine. Though cultivated and sold by a few coffee producers, Charrier coffee is widely considered inferior-tasting to its more famous caffeinated cousin, Coffea arabica, and has yet to catch on even with regular decaf coffee drinkers. However, several efforts are underway to hybridize Coffea charrieriana and Coffee arabica – or even genetically modify either species – to produce a naturally caffeine-free cultivar that preserves the flavour profile of regular coffee.

Low and non-alcoholic wines and beers, on the other hand, have a much longer history – if only because these beverages are significantly older than coffee and tea. In the Middle Ages, brewers commonly produced small beer containing only 2-3% alcohol by volume, which was drunk by absolutely everyone – including children. Regular drinking water was often contaminated with bacteria and parasites, which were killed off by the boiling and fermentation processes used in brewing.

De-alcoholized wine and beer, however, are more recent developments. Seeking to prevent inebriation among his parishioners, in 1869, American Methodist minister and teetotaler Thomas Bramwell Welch invented a flash-pasteurization process to prevent grape juice from fermenting. The resulting product, dubbed “Dr. Welch’s Unfermented Wine”, was marketed to churches as a non-alcoholic substitute for communion wine. The company Welch founded and which bears his name still exists today, and is best known for its line of grape and other fruit juices, jams, and snacks. Four decades later in 1908, the vineyard of Maria Jung in Rüdesheim am Rhein, Germany, experienced an unexpected slump in sales. Upon contacting her usual clients, Jung discovered that they were increasingly choosing to abstain from alcohol for health reasons. After pondering the problem, Jung came up with an innovative solution: why not use the distillery the family also owned to boil off the alcohol, producing non-alcoholic wine? Her son Carl – no relation to the famous psychoanalyst – soon developed a vacuum distillation process that better preserved the original flavour of the wine, and a German tradition of non-alcoholic wine was born.

Meanwhile, across the Atlantic, the development of de-alcoholized beer was largely spurred by the passing of the 1919 Volstead Act, which made the sale and consumption of “intoxicating liquors for beverage purposes” illegal in the United States. The Act defined “intoxicating liquors for beverage purposes” as those containing more than 0.5% alcohol by content – a cutoff which rankled alcohol producers. 0.5%, they complained, was less than the alcohol content of sauerkraut and not based on any scientific data on intoxication. In reality, legislators had simply borrowed this figure from the Internal Revenue Service, which used it to distinguish taxable beverages from non-taxable ones. Yet despite mass protests by alcohol producers and labour organizations – including a 20,000-man march down New York’s Fifth Avenue on July 4, 1919 – the Government held firm, and in the face of Prohibition breweries, wineries, and distilleries were forced to take creative measures in order to stay in business. Many major breweries, including Schlitz, Anheuser-Busch, Pabst, and Miller responded by producing “near beers” or “malt beverages” like Bevo, Pablo, Vivo, and Famo, which were regular beer which had been boiled to bring the alcohol content below the 0.5% limit. Amusingly, near beer was often surreptitiously delivered to customers with a separate package containing the alcohol which had been boiled off, which could be re-inserted into the beer using a syringe to create so-called “needle beer.” Yet while near beer was likely better than nothing for thirsty Americans, the flavour that resulted from the de-alcoholization process left much to be desired, leading one dissatisfied customer to quip: “Whoever called it near beer was a poor judge of distance!”

Other Prohibition dodges were even more brazen. In addition to near beer, many breweries produced malt extract, which, while perfectly legal in itself, could easily be mixed with water and yeast to produce home-brew beer. Similarly, Fruit Industries Ltd, a front company of the California Vineyardist Association, sold bricks of grape concentrate called Vine-Glo. Though officially intended for making grape juice, the Vine-Glo bricks came packaged with an oddly specific – and very cheeky – warning:

“After dissolving the brick in a gallon of water, do not place the liquid in a jug away in the cupboard for twenty days, because then it would turn into wine.”

With the repeal of Prohibition in 1933, the market for non-alcoholic wine and beer suddenly dried up – not to be revived for another four decades. In the 1970s, Texas-based oil worker Manny Zelzer spent a great deal of time travelling to and from the Middle East. There, many of his friends colleagues had developed a taste for American beer, and asked him to bring some back from home. However, due to Islamic prohibitions, many Middle Eastern countries had banned the production or importation of alcohol. Zelzer got around this problem by boiling his favourite brands to remove the alcohol before importing them. This de-alcoholized beer proved so popular that Zelzer soon launched his own brand, Texas Select, which by the 1980s was being sold across the Middle East and in countries such as Japan, Canada, and Korea. This was followed in 1990 by the launch of O’Doul’s, still one of the most popular non-alcoholic beers on the market. While initially slow to catch on, non-alcoholic beers and wines steadily grew in popularity thanks to growing public concerns over the negative health impacts of alcohol. Health concerns also spurred the development of low-calorie light beers, which tend to have a lower alcohol as well as carbohydrate content. Today, the non-alcoholic drinks market is worth over $11 billion worldwide.

One of the major reasons non-alcoholic wine and beer took so long to become popular is their poor reputation when it comes to taste. Unlike caffeine, ethanol is difficult to remove without stripping out beneficial flavour compounds like esters, flavonoids, and monoterpenes; or increasing the concentration of unpleasant-tasting compounds like tannins and acids. Furthermore, alcohol itself contributes enormously to the texture and flavour profile of these beverages, and can leave them tasting bland and watered-down when removed. This problem is most prominent in wine, which on average contains around 12% alcohol by volume. Beer, by contrast, contains on average 5% alcohol by volume and is comparatively easier to de-alcoholize without affecting flavour. Furthermore, beer typically contains other flavourings like hops which can potentially mask any flavour deficiencies produced by the de-alcoholization process.

Today, several different methods are used to lower or eliminate the alcohol in wine, beer, and cider. These techniques are classified according to when in the production process they are applied: pre-fermentation, fermentation, or post-fermentation.

Reducing alcohol content pre-fermentation involves reducing the amount of sugar in the grape juice or mash which the yeast can convert into ethanol. This can be done in a variety of ways. For example, trimming the vine leaves at various points in the growing process or harvesting the grapes early can reduce the amount of sugar that accumulates in the grapes themselves. Even simpler, the grape must or juice can be diluted with water prior to fermentation to reduce the sugar concentration. However, this act is actually illegal in many major wine-producing nations including Australia, France, Germany, New Zealand, and South Africa. Alternatively, the juice or mash can be passed through microfilters or treated with special enzymes like glucose oxidase to remove some of the sugar. Of course, some sugar must be retained otherwise fermentation cannot occur. During fermentation itself, alcohol production can be reduced by halting fermentation early or by using of alternative, non-Saccharomyces cerevisiae or NS yeasts which generate less ethanol than traditional yeast varieties. However, most wines and beers produced using these techniques still fall above the 0.5-1.2% alcohol concentration required to be classified as low-alcohol or alcohol-free, while the few that meet this requirement are typically inferior in taste. For this reason, most non-alcoholic wines and beers are produced by removing the alcohol after fermentation.

As previously discussed, the traditional method of removing alcohol from wine and beer was simply to boil it off. However, this tended to give the resulting product an unpleasant “cooked” or “burnt” flavour. This problem was largely solved by vacuum distillation, the technique developed in 1908 by German winemaker Carl Jung. The boiling point of liquids is dependent on ambient pressure; the lower the pressure, the lower the temperature needed, which is why water will boil at only 68 degrees Celsius atop Mount Everest as compared to 100 degrees at sea level. In vacuum distillation, the pressure in the still is reduced so that the temperature of the wine never exceeds 48 degrees, helping to preserve its flavour. Of course, many other volatile compounds including ethyl esters and aliphatic alcohols escape along with the ethanol, but these are typically separated out via fractional distillation and re-added to the de-alcoholized wine along with concentrated grape juice, tannins, natural flavours and other compounds to restore the original flavour profile. The primary advantage of vacuum distillation is efficiency, with the process being capable of bringing the alcohol content of wine down to as low as 0.02% in a single pass. The process is also widely used by wineries to make finer adjustments to the alcohol content of regular wines. However, despite measures to capture and restore volatile flavour compounds, some losses are inevitable, which is why more sophisticated de-alcoholization processes are increasingly being used to satisfy customers’ discerning palates.

One of the first major improvements to vacuum distillation technology was the spinning cone column or SCC, developed in 1991 by Australian food chemist Andrew Craig. This consists of a tall stainless steel column containing a rotating shaft and a series of spinning and stationary cones. The wine is injected at the top of the column and flows over the spinning cones, which produce centrifugal force that spreads the wine into a thin film. Air is then pumped out of the vessel and steam injected from the bottom in two stages. The first, conducted at 30 degrees Celsius, strips the wine of its volatile flavour compounds; while the second, conducted at 40 degrees, strips it of its alcohol. The volatile compounds are then re-introduced to the de-alcoholized wine in order to restore its flavour. By promoting greater evaporation rates at even lower temperatures, SCC allows for more efficient de-alcoholization and greater flavour preservation than traditional vacuum distillation, though it still suffers from unavoidable losses of volatile flavour compounds.

Due to its lower alcohol content and the need to preserve carbonation, beer is typically not de-alcoholized using vacuum distillation or SCC. Instead, a variety of “cold” methods are used including reverse osmosis. Very similar to the dialysis process used to clean the blood of patients with kidney disease, reverse osmosis involves forcing the beverage at high pressure through a semi-permeable polymer membrane surrounded by a stripping fluid – typically water. Typically, water will diffuse from a region of low solute concentration to one of high solute concentration (in this case, the beverage) but when high enough pressure is applied to the concentrated solution, the reverse occurs, and the ethanol from the beverage diffuses through the membrane into the stripping fluid, leaving most other compounds behind and preserving the original flavour. Furthermore, the process works at temperatures as low as 1-5 degrees Celsius, eliminating the danger of denaturing flavour compounds through heating. However, reverse osmosis also has a number of disadvantages – namely inefficiency, with the process only reducing alcohol by 0.7-1.5% per pass. Furthermore, the process requires the original beverage to be diluted with water prior to processing – which, as we’ve previously discussed – is illegal to do with wine in many regions.

A related process is osmotic distillation or evaporative perstraction. Like in reverse osmosis, the beverage is forced at high pressure past a semi-permeable membrane, on the other side of which a stripping fluid – typically water – is forced in the opposite direction, forming a counter-flow diffuser. In this method, the pressure of the beverage causes the ethanol to evaporate and diffuse through the membrane, whereupon it condenses in the stripping fluid and is carried away. Like reverse osmosis, osmotic distillation is carried out at low temperatures, preventing the denaturing of flavour compounds, but is slightly more energy-efficient.

Finally, the last major method used for de-alcoholizing wine and beer is nanofiltration, in which the beverage is forced through a semi-permeable membrane covered in tiny pores ranging from 1-10 nanometers in size, which allows nearly all the flavour compounds in the beverage to pass through while leaving ethanol molecules behind. This method allows larger volumes to be processed faster than reverse osmosis or osmotic distillation, reduces alcohol content by about 7-10% per pass, and operates at lower pressures, making it more energy-efficient.

And that, dear viewers, is how caffeine and alcohol-free drinks are made. Thanks to more than a century and a half of technological innovation, we can now enjoy some of our favourite vices while suffering almost none of the consequences – and isn’t that the very essence of human civilization?