THEY have won legions of fans and grown from a cottage industry to a major force in pubs and on supermarket shelves.

But now Scotland's army of microbrewers are warning their ranges of beers and ales may be about to jump in price after a hike in one of the industry's staple ingredients.

A bad harvest last year has resulted in a rise in the cost of malt barley, which is used throughout Scotland's micro-brewing industry.

So far, most producers have resisted passing their costs on to their customers, but now many are saying the price of a pint, bottle or cask may soon have to go up.

The cost of buying a ton of the malt barley used by micro- brewers has been rising in recent years, and stood at around £600 last year.

But 2012's wet weather and increased pressure on supplies has pushed up production costs by about 5%-8% this year, meaning the price of a beer will soon have to increase.

Jamie Delap, managing director of Fyne Ales, at Cairndow, Argyll, said costs were increasing and that would eventually have to be factored in to beer prices.

He said: "It's down to the weather situation last year. 2012 was a very wet summer and that led to very low yields at harvest time. If you are dependent on one type of crop, you are at the mercy of how the weather is in these specific places."

Scotland's microbrewing industry is booming, with a record number of breweries opening during the past decade.

Figures from the Campaign for Real Ale (Camra) show the number of establishments producing craft beers and ales north of the Border has doubled in 10 years. This renaissance in traditional drinks has added pressure to malt barley supplies, which come in many varieties.

The Scotch whisky industry, which is also enjoying higher sales, accounts for the lion's share of supplies, leaving some breweries looking to source their ingredients from as far afield as Germany.

Duncan Reid, sales manager at Loch Lomond Brewery, one of many popular microbreweries that have sprung up in recent years, said: "The bad harvest will have affected all types of barley and most small brewers. We have not made a decision on our prices yet, but I'd say that the cost of barley is up by between 5% and 8% for us.

"That said, business is pretty good and we've had a good start to the year."

The bad harvest has led to "tight" supplies of malt barley, said one producer, who brings grain to Scotland and the north of England, raising fears of a shortage on top of higher costs.

Gerald Michaluk, owner of the Isle of Arran Brewery, takes pride in sourcing all his ingredients from Scottish farms.

He said trying to get good malted barley had become difficult, and he is dismayed by reports that major brewer Tennent's has decided to start using Scottish barley exclusively in its products.

He said: "There is a shortage and we're considering importing grains from eastern Europe to mix with Scottish barley from the west coast."

James Davies, of Alchemy Brewing in Livingston, West Lothian, added: "We're also going to see an increase in tax when the duty escalator is brought in this year, and that will have a direct effect on the cost of beer and ales."

l Tom Bruce-Gardyne will host the Herald and Sunday Herald's craft beer event at Citation in Wilson Street, Glasgow on Sunday, March 24. For more information see www.herald-events.com/beer