In any walk of life, whatever your career, there are certain places you hope your job might take you. When I worked in advertising I always dreamed that a global ad agency might decide I was the only person who could help out on a special three-month project in New York, and fly me over there and put me up in an apartment until I’d delivered… I’m not sure what, the fantasy gets vague at that point. If you’re a lower league footballer, I’m sure you dream of playing at Wembley or even Old Trafford one day, and it’s a dishonest restaurant critic who claims they’ve never hoped to be sent to Noma or El Bulli to offer their unique perspective.

As a beer writer, I’m waiting patiently for my invitation for an all-expenses-paid trip to the hop farms of the Yakima Valley in Washington State. It hasn’t happened yet. But it will. This is where the hops are grown that changed everything. These hops began the American craft beer revolution, bringing with them a new palate of flavours that, over three decades later, remain the secret weapon in the fight to change the preconceptions of people who think they don’t like beer. These hops make people say things like, “Oh. Oh, I didn’t know beer could taste like that. Oh, that’s different. That’s not what I expected at all. I still don’t like beer, but I love this.”

Hops grow in temperate climates around the world. Like people, when they travel they change some aspects of themselves to fit in. American hops are widescreen and loud, occasionally brash and overbearing, but always exciting. The aroma and flavour they give to beer points to the horizon and encourages brewers and drinkers to go bigger, to reach for more. By contrast, European hops are more reserved. English hops are earthy and rustic, redolent of rainy autumn rather than stunning fall, the smell of loam and damp country lanes overhung by dripping trees. Their continental counterparts are balanced and refined. They might not seem that interesting to you, but if they don’t that’s because you don’t have the right breeding and class. The classic varieties are even referred to as ‘noble hops’. They don’t have to explain themselves to the uncultured.

It’s summer 2012, and an email arrives inviting me on a visit to some hop farms. There’s no transatlantic travel involved, but it will still involve getting on a plane. Greene King is brewing a new beer using hops grown in Slovenia. The head brewer is going out to inspect the farms he’s buying from, and the brewery thought some trade journalists might be interested in going along for the ride.

At this point, I’m not sure what to expect from Slovenia, being entirely and shamefully ignorant of anything to do with it. I always used to get it mixed up with Slovakia, which is unforgivable really, even though both are high in the rankings of nations that consume a lot of beer per capita. Both outstrip the UK, and Slovenia is ahead of the US, narrowly missing out on the top ten. It’s no Germany or Czech Republic, but Slovenia is a country with beer in its soul.

As we come in to land, the first thing that surprises me about Slovenia is its beauty. Again, I’m revealing my ignorance here, but for people who grew up in the 1980s, any former Soviet Bloc country remains grim and grey in the imagination. Such preconceptions have been instantly blown away for anyone who has holidayed in places like Montenegro or Croatia and found a relatively unspoilt Mediterranean paradise, but I never have.

Slovenia has only the tiniest strip of coastline, thanks to the Italian border creeping along and stealing it, a narrow sliver that seems to tell a story of blatant and shameless land-grabbing when you look at it on the map. But it doesn’t need the sea: Slovenia sits just south of the Alps, and much of it is mountainous and forested, dotted with lakes, fairy-tale castles and breath-taking views that rival any other Alpine tourism hotspot. The whole country seems tinged with an ozone-rich azure freshness. These mountain ranges are dense with rivers running through broad, pretty valleys that are perfect for either agriculture or sitting back and gazing at with a cold beer in your hand.

If you’re going to do that – and I recommend you do – there are two main brands to choose from: Union and Laško. Bitter rivals for over a century, they squeezed almost everyone else out of the market. Each produces a perfectly decent pilsner and a dark lager as well as soft drinks and radlers (shandy). With few product differences between the two, loyalty to one brand or the other became as much a badge of allegiance as your choice of team in a city with two rival football clubs.

In the early noughties, global giant Interbrew (now A-B Inbev) came sniffing around Union on its path to buying its way to global beer domination. Desperate to keep these twin national treasures in Slovenian hands, the Slovenian government gifted Union to Laško, creating a monopoly with a market share of over 80 per cent. Invariably, drinkers of either brand claim the beers are not as good as they used to be. But for an Englishman, the accent softening the ‘s’ in Laško creates an inevitable preference, if only for lame jokes about ‘going out on the Lashko.’

This beer obsession doesn’t automatically make Slovenia a perfect hop-growing region, but many other features of the country do. Sitting as it does with the Alps to the north, Italy to the West, the Mediterranean to the south and the bulk of Central Europe to the east, the small Republic of Slovenia – about half the size of Switzerland – has always been both strategically important and far too tiny to defend itself. As a result, at one time or another it’s been annexed by every significant empire that has waged war across Europe, and its borders have always been subject to change. About a third of modern-day Slovenia was for centuries part of the Duchy of Styria, a territory within the Holy Roman Empire split across what are now Slovenia and Austria. And it’s that name that should cause the ears of any brewer to prick up.

The Styrian Golding hop is popular in ale brewing, especially in the UK and Belgium. It’s a friendly, no nonsense hop with a noble profile, low in bitterness, and it adds a light spiciness to beers. When Greene King launched a golden variant of their flagship beer, head brewer John Bexon wasn’t looking for massive new flavours. He wanted to create a light, cask-conditioned ale that would appeal to lager drinkers. He could have chosen from a range of newly developed hops being lionised by the new wave of craft beer drinkers, but the combination of high demand and uncertain supply was too risky for a brewery of Greene King’s scale. So he decided to look at a back catalogue of hops – a regular source of good ideas that have been forgotten – and found something a little different from the norm, but also tried and tested in a commercial sense.

The morning after our evening arrival in Slovenia, a minibus full of Greene King employees and beer trade journalists winds its way up into the Savijnski river valley, in the heart of what used to be Styria. We climb close to a thousand feet above sea level, but the high-sided valley has a broad, flat floor with a microclimate that is perfect for hop growing.

After a couple of hours’ drive under huge blue skies, surrounded by mountains that always seem to keep their distance, we arrive at the Institute za Hmeljarvsto in Pivovarstvo Slovenje (IHPS), or Slovenian Institute of Hop Research and Brewing, in the small town of Zalec. The institute was founded in 1952 as a collective of local hop growers to help answer the most important questions in hop growing, concerning issues such as soil, fertilizer and climate. The main building looks more like a ski hotel than a scientific institute, apart from a fresco on the wall facing the road showing families at work in the hop fields. Long lines of hop plants run away to wooded mountains in the distance. A line on the introduction to the Institute’s website reads, “When hops scratch you just once, they scratch you forever.”’

The president of the Institute is Martina Zupancic, a Knight of Order of the Hop, as presented by the International Hop Growers Bureau. In her office, she tell us that the main focus of the Institute’s work is cross-breeding hops, not necessarily for flavour, but to make them more robust and resistant to disease. Hops are fickle, fragile plants, and they need toughening up. “There has been quite a lot of rain so far this year,” says Martina. “This is good for the wheat, but it means the hops are late – they’re only just flowering now. Man-made climate change is a fact, and it is really disturbing the growing season.”

Climate, and the hop’s reaction to it, are ultimately is what brought us here. Hop cultivation in Slovenia has been traced back to the eleventh century, when they were grown by the monks who were the first to brew beer on a large scale. The first industrial-scale hop gardens were planted here, near Zalec, a hundred and fifty years ago. The first commercial varieties, imported from Germany and the former Czechoslovakia, proved vulnerable to disease, but English varieties fared much better.

Not every hop variety prefers the Slovenian climate to its native country, but once they had taken to their new surroundings, the English immigrants prospered. They started winning international competitions, and some were hailed as the best in the world. In 1926, an outbreak of mildew caused widespread destruction across the hop fields, but the Styrian or Savinjski Golding survived and prospered. It seems obvious from its name that the Styrian Golding is a descendant – an ecotype – of the English Golding hop that was exported here in the nineteenth century. Obvious, but wrong. It’s actually an ecotype of Golding’s relative, the Fuggle. Now praised for its noble qualities – low bitterness and high, refined aroma – it is regarded as a traditional Slovenian variety, accounts for 20% of the country’s total crop and is one of the most important export varieties. Incredibly for such a small country, Slovenia is now the sixth largest hop grower in the world, with over 1200 hectares under cultivation. Even such enthusiastic drinkers as the Slovenians find themselves with a surplus, and 90 per cent of the crop is exported.

As I sit taking studious notes in Martina Zupancic’s office, the story of how an English import became a Slovenian export slowly reveals the true magic of the hop. The reason English hops thrived in the lower Slavinja river valley is that they loved the climate. Here on the south side of the Alps, the mountains protect the fertile soil around the river networks. The amount of rainfall during the growing season is usually just right – about 800mm – and the climate needs to be sunny and pleasant without exceeding 30 degrees Celsius, which would start growth too early. Essentially, the valley’s microclimate is pretty similar to that in the English hop gardens of Kent and Herefordshire, but more stable and predictable. Those rare months in England when everything fits just right and it reminds you of the endless summers of childhood are more regular and reliable here – at least until now and the climate change that is worrying Martina.

But what makes these hops Slovenian, as opposed to merely successful English ex-pats, is their reaction to the climate. Here at the Institute, they carry out a chromatographic plot of the essential oils in each hop. It is these oils which give a hop its aroma, and there are 300 different components, which explains why the aromas in hops are so complex and so diverse. When measured all together they create a graph with 300 points, spiky and stark, like the remains of a petrified forest. Each different hop variety has its own plot, as unique as a fingerprint. Among other things, the Institute uses these chromatographic plots to tell if a hop is genuine – it’s surprisingly common for people to try to pass off a lesser hop as a more noble variety. But when hops are planted in a different climate, the variations in soil, rainfall and temperature cause this chromatographic plot to change. Imagine if moving to another country caused your personality, even your fingerprints to change, and you understand how an English Fuggle can become a Savijnski Golding. The French concept of terroir, so beloved of wine buffs, is at least as important in hop cultivation, changing and defining the very nature of a hop. The Fuggle is noted for its earthy, spicy, herbal notes, with no fruit or citrus. A century after settling in Slovenia, we’re here because John Bexon has come in pursuit of what he calls the ‘lemon and tinned peach aroma’ of the Styrian/Savijnski Golding.

It’s time we saw some of these hops up close, so we pile back onto our minibus and head to one of the farms which is a member of the Hop Institute, just a short drive a little further up the valley. We receive a warm welcome from the family who own the farm, and before we go to look at the hops, they insist that we sit at a shady table on a pretty terrace and share a little snack. As well as growing hops, the farm also grows corn and apples and breeds pigs, and from some of these they make their own salami. Now, ten of us sit around a table punctuated with ice buckets full of the locals beers, and groaning under the biggest plate of salami I’ve ever seen in my life. There are drifts of it, mountains of it, sweating slightly and shimmering in the sun. Then there are plates of bread and cheese, similar in bulk, modelled to resemble the peaks that sit behind us.

The first piece of salami is a flavour explosion. I dig in, alternating salami, cheese and beer while the business part of the meeting is discussed somewhere else further up the table. Finally I sit back, pleasantly stuffed. Our hosts look up, look at us. Look at me. Look hurt. Our guide explains that it would be polite for us to finish the plate of salami, and we’ve hardly dented it. Politeness – that scourge of English health both mentally and physically – kicks in. I’m not actually that hungry. Last night we were taken to a brewpub and pizzeria on the outskirts of Ljublijana where we were treated to fantastic beer and interesting food. There was sausage and deer goulash and pork ribs and calf’s liver and roast pork and horseradish and dumplings. I had thought I had escaped dumplings when I last left the Czech Republic, but you can never escape dumplings, I’ve accepted that now. Most of all, there was ‘minced lard with soft pork crackling’ – something a British celebrity chef might rename ‘two ways with pig fat’. It was grease presented as an art form, soft and shiny with juicy flecks of meat contrasting with hard, chewy rind. It was better than I make it sound, and was complemented wonderfully by the brewpub’s pilsner, which harmonised to create a salty, fruity, sweet taste sensation, then cleansed greasy, shiny lips and suggested more lard might be a good idea.

The following lunchtime I’m still reliving the experience. But the insistence of our hosts seems to have gone beyond good-natured japery and become quite serious. It seems we will genuinely cause offence if we don’t clear the mountain of homemade salami before us. One by one people drop out until its just John Bexon and me, two big blokes among mainly slim female journalists and PRs, tackling endless sweaty fat-flecked disks. Pig fat starts to ooze from my pores and sizzle under a high sun that has swung from behind the farmhouse to look down on us and mock. Again and again comes the repeated demand of “eat, eat.” We know we will not be taken to see the hop fields unless we can complete this endurance test, this initiation rite. Politeness, the cause of more disputes and fallings out in Little England than honest confrontation could ever match. Politeness, the grinning totalitarian thumb under which the English are squeezed. Politeness is about to kill me.

Finally, after what seems like hours, with the help of a combination of cool, refreshing beer and mental exercises that take my brain to a far away happy place where I am an eighteen year-old vegan, Bexon and I manage to clear the plate. Our hosts cheer and clap. My fellow journalists and the PRs from Greene King look at us like we are titans from Greek myth. We have bested great beasts here, just as Hercules triumphed in his many tasks. Now, finally, we’ll get a tour of the hop fields. Or at least, we will when we’ve cleared the other plate.

What other plate?

One of the farmers leans back: Bexon and I are at one corner at the bottom of a table around which about a dozen people are seated. We didn’t think that one measly plate was for the whole table did we? At the top end sits another Matterhorn of meat, one more peak of pork, at least equal in size to the one we just bested. Our grinning hosts pass it down towards us. Because what’s become obvious to everyone now is that Bexon and I really like salami. A lot.

I’ve often found that whining like a caged animal is a good way of cutting through potential cultural barriers. After no more than a quarter, maybe a third, of the second plate, we are slid from our seats, our greased skins compensating for our dramatically increased bulk. Amazed that I can still walk, disoriented by the sun and feeling quite unusual, I follow the rest of the party out towards the hop fields, unaware that my day’s polite intake of pig fat has only just begun.