It was only a matter of time before The Apprentice jumped on the craft ale bandwagon.

"Flavoured beers are the latest trend in British brewing. Tap into a taste that hits the spot and you can turn hops into hard cash," breezed a voiceover in a recent episode as the band of wannabe entrepreneurs headed for a brewery in the Midlands.

Of course it was a shambles that built to Lord Sugar's inevitable punchline: "You lot couldn't organise a piss-up in a brewery." A fair comment after their attempts to sell a revolting-sounding brew of rhubarb and caramel to middle-aged Morris dancers at a beer festival in London.

"Yeah, it was hideous," says Andrew Barnett, otherwise known as Barney, who worked for the Midlands brewery before studying brewing at Heriot-Watt University in Edinburgh. He is now the brains behind Barney's Beers, which began life in a brew-pub in Falkirk. Searching for a new home in Edinburgh in 2012 – somewhere more inspiring than an industrial unit beside the bypass – Barney contacted Summerhall, the old Royal Dick Vet college by the Meadows and now the city's latest arts venue.

He left his name and number and thought, "That'll be the end of that." "Then literally within a few minutes," he recalls, "the guy who's now MD rang back saying 'A brewery? You're joking?'"

It was perfect timing as Summerhall's new landlords had just discovered the place had been brewing beer for centuries – long before veterinary students began chopping up rats there in 1916. Indeed the original brewer signed a petition against the malt tax of 1725 which led to a brewery strike in Edinburgh and a riot in Glasgow.

At its peak, the Summerhall Brewery was one of more than 40 in the city and it alone employed 129 people. You wonder what their ghosts would make of its latest incarnation as a five- barrel micro-brewery where once it sprawled across the entire site. Hopefully they would enjoy the beers as much as everyone seemed to at the Summer(Beer)hall Festival two weekends ago. Among the young, mixed crowd I spotted only a few beards, even fewer beer bellies and definitely no Morris dancers.

Besides Barney's Beers, there were brews from Bristol, Bavaria and Sierra Nevada, while closer to home were Inveralmond ales, whose MD Fergus Clark told me "there hadn't been a brewery in Perth for 33 years until we opened in 1997". Unlike remote distilleries, which can remain closed for decades until demand for whisky picks up, breweries are usually located in towns and soon bulldozed into car parks or supermarkets if ever they shut.

Craft brewing is booming and Clark estimates there are more than 80 micro-breweries in Scotland. "Probably the biggest influence has been the progressive beer duty brought in in 2002," he says, referring to one of the best things Gordon Brown ever did as Chancellor. It opened the doors to small brewers and was perhaps a belated apology for the despised malt tax.

With good timing, Aldi is currently hosting its second Scottish beer festival with beers from Knops, Tryst and others, while July 20 sees the Blackwaterfoot Beer Festival at the Kinloch Hotel on Arran.

Barney's Red Rye

£2.10, Great Grog, Cornelius, Hippo Beers (4.5%, 330ml)

Preferring his beers to be light, as in pilsners, or dark like stouts, Barney set out to create something in between using rye and his favourite German malt. It works really well with its fruity flavours balanced by a malty bitterness and some spicy hops.

Inveralmond Thrappledowser

£2.49 Great Grog, Hippo Beers (4.3%, 500ml)

There is something about the word thrapple that implies dust and dryness, and if your throat is feeling that way, then why not oil it with this tasty, amber brew with its grassy, floral nose and bittersweet, slightly salty, earthy flavours.

Orkney Blast

£2-£2.80, Aldi and good independents (6%, 500ml)

This is dangerously tasty stuff from the Highland Brewing Co on Orkney that won champion beer of Scotland in 2010. It has a lovely full-bodied, malty sweetness in the middle offset by the English hops which give the beer its firm and dry finish.