The report analysed the standards of hospital food
One in five hospitals is failing to meet the nutritional needs of patients, according to an NHS report.
The first major analysis of food being served in Scottish hospitals also found NHS boards achieved a score of 87% for catering standards overall.
Health secretary Nicola Sturgeon said a new database to analyse menus would help ensure hospitals were offering healthy meals.
She said: "Every patient has the right to expect decent, nutritious food."
According to the Health Facilities Scotland (HFS) report, 80% of catering facilities across the NHS in Scotland provided meals meeting the nutrient requirements of a 'general' hospital population.
But three health boards failed to achieve this standard, including NHS Tayside which had the lowest pass rate of 45.5%.
NHS Borders scored just 50% and NHS Fife 60.2%, while NHS Greater Glasgow and Clyde achieved the highest rating at 90.7%.
The analysis, carried out between July and December last year, assessed provision of hospital meals against seven key standards.
Most hospitals were found to be providing a good range of food types and catering for special dietary requests, the only two areas in which health boards scored more than 90%.
The lowest compliance rate was for the provision of modified diets to help patients with particular conditions, with a score of 75% across Scotland.
However, only NHS Grampian failed to pass the patient experience standard, which measures how well catering staff respond to concerns, with a pass rate of 68.2%.
The new nutrition database is aimed at helping hospitals tailor meals to meet the needs of individual patients and allowing information on recipes to be shared across Scotland.
Ms Sturgeon said the government was committed to providing patients with the best nutritional care possible.
"For the first time this report shows us the nutritional ratings achieved by the NHS and provides a standard against which progress can be measured," she said.
"By this time next year I expect all health boards to achieve over 90% for every one of the food standards."
Paul Kingsmore, director of HFS, said the assessment was an "initial snapshot" which would be followed by further regular reports.
"But together with the nutrition database, it lays the vital groundwork for the NHS to do even better in the future," he added.