An Evening News probe found that more than 74,000 meals were binned in 2014/15, with the total likely to be much higher as NHS Lothian could not give figures for smaller facilities such as Astley Ainslie Hospital – or for the Edinburgh Royal Infirmary where meals are provided as part of the private finance deal.
Health chiefs said that some meals were wasted due to patients deteriorating, being discharged or moving wards.
But others said many patients refused to eat hospital food because of its poor quality.
Tory health spokesman Jackson Carlaw branded the figures as “an inexcusable waste of public money”, as patient campaigners questioned whether the quality of food served was affecting levels of waste.
Mr Carlaw said: “Inevitably some meals will not be consumed but this will surely be less likely to start with if they are both appealing and beneficial in the first place.
“These new figures add injury to a hospital food farce which has gone on for too long. Disgusting doesn’t cover it.”
NHS Scotland spent around £87 million on catering services during 2014/15, which equates to £87 per patient each week, according to government figures.
Hospitals in Lothian have previously come under fire for sub-standard meals, where families have had to bring food in for elderly relatives.
Dr Jean Turner, patron of the Scotland Patients Association, said: “I have visited friends in hospitals before and heard from patients who agreed sometimes it is hard to tell what you are getting – whether it was mushroom stew or a beef stew or whatever. It’s hardly appealing.
“Food and drink are some of the most important parts of the recovery process.
“We are all paying for it and the private companies are getting something out of it whereas patients are losing out.”
George Curley, director of facilities of NHS Lothian, said: “Meals that go uneaten are left untouched for a number of reasons, including the patient being discharged, moving ward or being too ill to eat.
“We always have to supply every meal, even if a percentage of them may go untouched, because we know that food plays such a key component in recovery and patients must have the opportunity to eat.
“Food wastage refers to the number of meals that are created and then left untouched. Factors such as quality, taste and menu choice are not relevant because it does not apply to the number of meals that have been part-eaten and returned to the kitchen.”
A Scottish Government spokesperson said there was a strong set of nutritional standards already in place for hospital food and new guidelines will be introduced shortly.