PATIENTS are being fed for little more than £4 a day in Scotland's largest health board - barely enough to buy a coffee and cake in a high street chain cafe.

Amid growing anger about the ­quality of food in hospitals, figures released by NHS Greater Glasgow and Clyde show its catering budget was cut by almost £1 million last year and the number of staff working for the kitchens has been slashed by almost one-fifth in four years.

A major re-organisation of the way patient meals are prepared in the region took place during 2011 and 2012 and now all hospitals are served by two "super kitchens" where the ingredients are cooked and blast-frozen.

The health board insists patient satisfaction with catering is at an all-time high. However, since Herald columnist Anne Johnstone, who is being treated for leukaemia at the ­prestigious Beatson West of Scotland Cancer Centre, began campaigning for better food this summer, more concerns have emerged.

Read more: The inedible food that undermines high quality care

David Maguire, a successful Glasgow restaurateur and the co-founder of reservation web service 5pm Ltd, will take part in a review of the board's catering services to see how they could be improved.

He said: "I am a huge fan of the NHS. The NHS has saved the lives of three members of my immediate family: my wife, my father and my sister. It is providing world-leading facilities, but it cannot make toast."

The health board, which has already started to make menu improvements, is arranging for him to visit one of the super kitchens at Inverclyde as part of the review being developed.

Mr Maguire said: "The managers are of the view that the food produced at Inverclyde is of an acceptable standard. One of my jobs is to look and see if that assumption is valid."

Mairi Harvey, who served on inspection panels for the former Scottish health service watchdog NHS Quality Improvement Scotland, raised concern about the quality of food her father-in-law has been served at Vale Of Leven Hospital, Dunbartonshire.

In a letter to The Herald, she said: "While I cannot fault his nursing care, the food he has been given to eat is, in his words, 'pig swill'. He is losing weight at an alarming rate, and we are now bringing in sandwiches, cakes, fish suppers and anything else we can think of to encourage him to eat."

Figures released under Freedom Of Information legislation revealed the health board's catering budget was cut from £18.67m in 2011-12 to £17.72m in 2012-13 and the number of staff working full-time in the sector has fallen from 490 in 2008-09 to 401 last year, an 18% decrease.

Although the board said it did not "routinely hold" data about the cost of each adult in-patient meal, it provided estimates for the total cost of all food and refreshments provided per patient per day. This was £4.92 for West Glasgow hospitals, including the Beatson, and £4.08 for other hospitals across Greater Glasgow and Clyde.

A spokeswoman for the health board said: "Good nutrition is core to effective care and a patient's recovery. We have therefore recently completed a package of investment of some £10m to create two new kitchens that cook fresh, nutritious, healthy food supplied to all our hospitals.

"The menus these kitchens provide have all been specifically developed by an expert group, including caterers, dietitians, nurses and patients, to ensure the nutritional needs of our patients as defined by national nutritional standards can be met."

A specific plan on food served to cancer patients at the Beatson has been developed, which included surveying patients about additional menu options, introducing more appetising snacks.

The spokeswoman said the peer review process was under development and would help to provide feedback from a patient's point of view.

She added: "Mr Maguire's extensive experience and knowledge of the catering sector will be an asset to the programme.

"We believe we offer a high standard of catering, but are in no way complacent and therefore see the public peer review programme as a valuable tool in our programme of continual improvement."