"Think about all our national dishes, although we think of them going with wine these days, originally they would have been drunk with beer and we are rediscovering the fact that our national menu goes with our national drink.

"Look at the number of people who have started to drink real ale because there are now so many new and interesting types available. People are starting to realise its not just the same drink going out under a different label."

George, 37, has been running the family business with his younger brother, Tom, after their parents, Richard and Lesley, retired in 2001.

The firm, based in Terrick, was founded in 1980, and was one of the first of the new-wave micro-breweries in England. Now by some margin the oldest working brewery in Buckinghamshire, it has won numerous awards for its beers, pub outlet and its commitment to sustainability.

The Chiltern Brewery has grown to provide beer for a staggering 300,000 pint glasses every year and has also diversified into other products such as jams, sausages and cheese which contain their produce.

It also offers tours to show the brewing process, and has taken over The King's Head pub in Aylesbury.

"Business is going well," said Tom, 34. "We have grown considerably for a number of years - the last five or six years have each set a record on the last."

Part of their success stems from the increasing awareness of locally sourced produce and sustainability - something the two siblings are particularly aware of too.

"We have been bashing away at all those things since we started," said Tom. "Our market is growing because people want quality local produce."

The pair plan to upgrade the processing machinery to increase capacity, which will help meet a new contract with The National Trust to supply their beer at a national level. But they say they are determined to keep the emphasis on providing a friendly, family service.

"One of the reasons we have such loyal customers is that we are a family business," said George. "I think that feeling of coming to a family business comes through to the customer here and at the pub. Once you get to a certain size that feeling is lost, and we don't want that to happen."

"We are not here to take over the world in three years," he added. "We have to continue with our business model and make sure what we are doing is manageable and organic growth and maintain the service and quality we are known for."

One of the biggest moves for the brewery was taking over The King's Head pub in 2005, something which in hindsight has proved a very smart move.

"It has worked out very well," said Tom. "We knew when we went in there what we wanted to do and it was a question of whether Aylesbury wanted it too and they did."

The pub, which offers real ales rather than the generic branded beers, and was one of the first in the country to ban smoking, loud music and gambling machines, has brought The Chiltern Brewery's products to a wider audience, and trade in the Terrick shop has also increased as a result.

"It is strange," said George. "You offer variety and choice by not offering the national brands. Fortunately we were not the only two people in Bucks who wanted the same thing."