When production started at Scotland's northernmost grain distillery in Invergordon during July 1961, the initial omens were not good. The late Yorkshire-born excise officer and author Irvine Butterfield was based at the site and recalled that the stillman was a former baker's roundsman, with no previous experience of distilling.
Interviewed for The Whisky Men a decade ago, Butterfield noted: "When they began to do the first distillation the whole plant shook like crazy. Worried, the stillman asked me what I thought was wrong. I told him I wasn't sure, but that I was going to get off the viewing platform immediately because something was obviously wrong and the whole place might blow up.
"The stillman closed the still down and we eventually discovered that no water was getting through because a ball cock in the water supply tank was rusted up. We also discovered a slight bend in one of the pipes, and the whole still column had obviously been very close to buckling and imploding at the time we shut down the still."
However, the distillery - established by Invergordon Distillers Ltd - survived those early teething troubles and has quietly gone on turning out large quantities of well-regarded grain spirit for more than half a century. In 1963 the initial column still was supplemented by two more in order to substantially upgrade capacity, and two years later Invergordon followed the prevailing trend of installing a malt distilling plant within existing grain distilleries.
Christened Ben Wyvis, the facility was equipped with six cast-iron washbacks and two 10,000 litre pot stills, and turned out malt spirit for blending until falling silent and being dismantled in 1977. A fourth column still, for the production of 'grain neutral spirit' was installed a year later, but has now been decommissioned, and only one grain whisky still remains in situ.
Ownership of Invergordon passed to the aerospace specialist Hawker Siddeley in 1981, and seven years later Dr Chris Greig led a management buyout, which held sway until a bitterly contested takeover battle was won by Whyte & Mackay Ltd in 1993.
As master blender Richard Paterson notes: "One of the chief reasons for Whyte & Mackay buying Invergordon Distillers was to get the grain distillery. Having that gave us a major degree of independence for blending."
Logistically speaking, however, anyone looking at a map of Scotland's grain distilleries would surely be puzzled by the location of Invergordon in comparison to its fellow grain plants, both past and present. Relative proximity to Central Belt areas of population and blending and bottling facilities is something of a logical prerequisite, yet Invergordon is situated 25 miles north of Inverness and almost 200 miles from Whyte & Mackay's Glasgow head offices.
The raison d'être behind the distillery's relatively remote situation is that during the 1950s, '60s and beyond, various governments and their agencies were keen to encourage sources of employment in Highland areas already suffering seriously from depopulation, offering generous incentives to companies prepared to locate their operations there. So it was that the historic port and naval base of Invergordon gained a grain distillery, with the site also offering a cheap and plentiful supply of water and relatively straightforward disposal of effluent.
The Invergordon facility offers an interesting contrast to Whyte & Mackay's showpiece malt distillery of Dalmore, just over two miles to the west. While a significant amount of money has been spent at Dalmore during the last few years in order to impress the visiting public, Invergordon is effectively an industrial site, with no public access and no pretensions to be any more aesthetically pleasing than it really needs to be.
There is also the small matter of scale. Dalmore can turn out 3.7 million litres of spirit per annum if working to capacity, while the comparable figure at Invergordon is 36 million litres, or almost 10 times as much. As production director Ian Mackie notes: "The site covers 120 acres and employs 100 people, mainly on the warehousing side of the operation. We have our own cooperage and a laboratory."
While most grain distilleries switched from using maize as their principal cereal to wheat for reasons of cost some years ago, Invergordon has now switched back again, as Ian Mackie explains. "For the past nine months the plant has used imported maize, and the main reason for this is that during the last five or six years wheat varieties have changed so that they have longer 'heads', at the same time as a deterioration in summer weather. The result has been that a high percentage of small corns are now grown which the plant at Invergordon can't process effectively, and this has caused fairly severe disruption to production over the last five years and very significant cost to the business.
"The maize is grown in south-west France, and the new-make spirit is a bit heavier, slightly rubbery and with a sulphury note, but that matures out, and Richard Paterson really likes the spirit made from maize as a blender because it has real character to it."
According to Paterson: "We principally use it at three and a half to four and a half years of age. It allows the malts in a blend to come together and shine through, giving it a real warmth. Invergordon has a lot of soft, floral honey notes and is light to medium in body. When aged for between 12 and 20 years for our older blends it gives a lovely honey and vanilla note."
"Our main investment in recent years has been in warehouses," says Ian Mackie. "We've built five new ones in the last three years and we have plans for another five. We've now got 51 and all but 12 are palletised."
The convenience of 'palletisation' is that six casks on a pallet may be filled at one time from a six-head filling machine, and then transported into a warehouse, reducing labour and increasing safety in terms of handling.
"We keep the racked dozen warehouses for smaller volumes and older whiskies which we need to move more often than most of the grain spirit," explains Mackie. "We mature and vat lots of different whiskies on site and we have 'finishing' casks for The Dalmore and Jura, too."
Richard Paterson adds: "Invergordon stores lots of our aged malts, and we carry out our blending there and also have marrying vats for the Whyte & Mackay blends."
At the time of writing the future ownership of Invergordon is uncertain. With Diageo now effectively holding a controlling interest in Whyte & Mackay, it seems unlikely that the world's largest spirits company will either want - or be allowed - to keep so much additional grain spirit capacity, and the likelihood is that the distillery will be sold off. Whoever buys it will need to invest in updating the production plant, which is undoubtedly showing signs of age, but such investment would result in a highly valuable asset at a time when it seems the world just cannot get enough blended Scotch whisky.
88,000 tonnes of maize and malted barley are used each year.
Three cookers, each of 70 tonnes capacity, cook the maize at 145 degrees C for 10 to 15 minutes.
One mashtun - each mash comprises 16.7 tonnes of maize and 37 tonnes of warm water, along with 1.45 tonnes of high nitrogen malted barley. Contents of the cookers is blown into the mash tun to mix with malted barley ground and slurried in cold water to give a final temperature of 62.7 degrees C.
Invergordon is the only distillery in Scotland to operate continuous fermentation, and the maize ferments for 24 hours in continuous cascade fermenters, then for a further 12-24 hours in 'batch' fermenters, or washbacks. 23 washbacks, 14 with capacity of 300,000 litres, and nine of 220,000 litres.
The wash has an alcohol content of 11/12 per cent when pumped into the three-column still, which comprises an analyser, a rectifier and a feints stripping column. The distilled spirit comes off the still at 94.4 per cent.