IRN-BRU: the people’s ginger. The west of Scotland generic term for a soft drink is apt in this case, as the liquid under advisement is ginger-coloured, or rusty as some see it, in a nod to the iron alleged in the name.

So, let’s clear that one up right away. Does Irn-Bru actually contain iron? Well, you may be surprised to learn that the answer is … yes! But only a tiny amount: 0.002 per cent of ammonium ferric citrate.

Other ingredients of the main un-dieted, un-energised brand are: carbonated water (natch), sugar (controversial), citric acid (yummy!), flavourings (including caffeine and quinine), sweeteners (aspartame, acesulfame K), preservative (E211), and colourings Sunset Yellow FCF and Ponceau 4R – oh, that explains the hue (though I can’t see the expression “I fancy a can of Ponceau”).

At any rate, readers, do not try making this at home. Apart from the water, it’s all arguably controversial (same with nearly all fizzy drinks, mind). The company website goes out of its way to insist that aspartame has been “thoroughly researched” and given the all-clear umpteen times by British and European authorities.

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As for the colourings, there’s a warning that these “may have an adverse effect on activity and attention in children”. But, again, colourings are all over the place nowadays, particularly in soft drinks.

Alcohol isn’t listed above, though there is a teeny trace element, which worried the Muslim community for a bit, until it was acknowledged that you’d probably have to drink around 5,000 cans in half an hour to feel any effect. Knowing Scotland, though, it’s probably been done.

More recently, proper manly sugar, as opposed to sweeteners, has been the main bone of contention. In 2018, there was a stushie. That year, a sugar tax was implemented in the UK, and AG Barr, the makers of Irn-Bru, changed the formula to avoid the tax. In the past, they’d probably have gotten away with this no problem. But, today, we live in an online world and what do we find online, readers? Correct: fury.

The outrage was palpable, or at least virtual. A Save Real Irn-Bru campaign was launched. Folk started stockpiling the “proper” stuff. There was even talk of a boycott.

But Barr said you couldn’t tell the difference, and argued that “most consumers want to reduce their sugar intake” anyway, on account of not wanting to get obese, like.

Besides, there’d been a Low Calorie Irn-Bru launched in 1980, which was relaunched in 1991 as Diet Irn-Bru and again as Irn-Bru Sugar Free in 2011. Still, the argument remained about having the choice.

Today, the company produces, Irn-Bru, Irn-Bru Sugar Free, Irn-Bru Xtra, Irn-Bru Energy and Irn-Bru Energy No Sugar. The last two are aimed at keep-fit folk though, in my experience, all “energy” drinks just make you burp on every push-up.

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All the tins of the various brands feature an image of a moustachioed, Victorian strong man, lifting – on the energy ones – a weight twice his size. Irn-Bru has always projected this image of strength (Scottish hard man: “I’ll hae the Sugar Free, please”), but I think the evidence for it increasing the size of one’s biceps is slight.

The strong man logo is said to have been based on an image of Highland Games athlete Adam Brown, and a constant theme throughout the product’s history is that it gives you stamina.

The official story goes that, in 1901, steel workers rebuilding Glasgow Central Station were drinking too much beer to quench their thirst. So, local aerated water business AG Barr supplied them with “a tonic-like drink made from caffeine and sugar”.

The Herald:

The workers said, “Aerated, eh?”, and took to the new concoction like a duck to mineral water.

The company says that, to this day, a principal purpose of Irn-Bru is to get Scots through “tough situations”. Today, this is thought to mean hangovers.

The origin of the name Irn-Bru is foggy. The drink given to the Glasgow stations workers is said to have been called Strachan’s Brew originally. It may have been changed to Iron, as that’s what these tough proletarians worked with.

However, Scottish researcher David Leishman discovered that “Ironbrew” was originally an American drink, created in 1889 to rival Coca-Cola. An advert from the time describes “a combination of Vegetable Tonic and delicious Aromatics, enriching and strengthening of the blood, muscles, brain; regulating the stomachic and nervous system; relieving headache, nausea, dyspepsia, sleeplessness, general debility”.

It sold well until US legislation decreed that adverts had to be true. Something slightly similar happened here in 1946, when the advent of new food labelling regulations saw the name of the Scottish product changed from Iron Brew to Irn Bru “because,” according to the company, “although it contains iron, it has never been brewed”.

So it’s Bru noo, and is branded today as “the strong soft drink”. From the mid 1970s to early 90s, Irn Bru was memorably advertised as “Your other national drink, made in Scotland – from girders!”

Latterly, the product has been associated with outré ads, the latest (for Irn-Bru Xtra) featuring a bald man’s wig walking out on him because they never do anything any more (“I want to be windswept!”). Tough voice: “Irn-Hairdoo: get some Irn in you.” An earlier one featured a lady saying Irn-Bru Xtra lets her talk to animals. “Hello!” she says to a squirrel. “Eat ma nuts!” replies the squirrel testily.

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The Barr family is still very much involved in the business. When Robin Barr retired as chairman in 2009, he passed the “secret recipe” for Irn-Bru on to his daughter, Julie, the company secretary. As the ingredients are now public, it’s not known what the secret is: perhaps some sort of incantation or ritual.

If so, it will be performed at Cumbernauld, now site of the HQ and production hub after a move from Parkhead, Glasgow. Whatever the mysteries, Irn-Bru remains Scotland’s other national drink. Today, of course, our other national drink is latté.