IT is one of the most important meals of the year and, as many a hard-pressed cook will know, it takes a fair amount of elbow grease to bring to the table.

But while in most households Christmas lunch only requires them to deal with a few pots of sprouts and other vegetables, one turkey and a modest amount of stuffing, catering staff at Barlinnie Prison, Scotland's largest, have been busy preparing festive fare on a truly industrial scale this week.

The prison kitchens have been alive with activity this week as teams of caterers and their helpers from within the prison population got to grips with the mammoth task of making a proper Christmas dinner for 1340 inmates - all served piping hot, and at the same time.

On the menu are more than 1500 portions of turkey, 3000 "pigs in blankets", 2500kg of potatoes - which will have to be peeled, boiled, steamed and roasted - and enough gravy to fill a 200 gallon tank.

On top of that, there's a mountain of 42,000 Brussels Sprouts to be prepared and 200 gallons of desert sauce and custard for afters.

Three days of preparation are required to cook the festive feast, and tomorrow the hard work will begin at 6am as the catering staff prepare to get lunch ready for 12 noon.

A total of 12 managers will be in charge of 45 inmates who work in the kitchens, directing them as they get down to the business of feeding their fellow prisoners.

Catering Manager George McGhee, a veteran of many Christmas lunches at the jail, said there was a good atmosphere on the day but that the prisoners know they are in for a hard shift.

He said: "The first thing they will have to do is serve breakfast at 8.30am, and the prisoners get a cooked breakfast on Christmas Day, so the work starts straight away.

"Then prisoners will be split into teams of about six and they will all have their jobs to do, like slicing the turkeys or preparing vegetables.

"They have to make sure they are in the right frame of mind when they come to work in the kitchen, because some prisoners have never done a day's work before and don't know how hard it can be. But we supervise them through that and get them going."

Given the pressure they are under to deliver a good meal, it could be expected that the Barlinnie chefs have dealt with their own share of kitchen nightmares before Christmas.

But Mr McGhee said the preparation for the meal was now a finely-tuned operation and that everyone involved was motivated to do well.

He said: "They always do a good job because they are doing it for themselves to enjoy and when they are working towards something that's for their own comfort they are happy."

"It runs like clockwork, although I should probably not say that or we will have a disaster this year!"

Cooking in the kitchens has also had a beneficial effect on some prisoners once they leave Barlinnie, with qualifications in catering available to those who wish to take them.

A Scottish Prison Service spokeswoman said: "Christmas is a time of gathering and giving. The serving of a festive menu in our prisons is a small gesture to mark the season, which can be a difficult time for many in our custody who are separated from their loved ones."