A report for the U.K.’s Highland Council documented more than 160 food hygiene complaints that were investigated by officials last year, including one claiming a caterpillar was found in vegetables served at a table and another claiming to have found a fly in a frozen baguette.

The report by principal food safety officer Alan Yates also reveals that officials sent 1,168 warning letters to establishments alerting them to contraventions of public health legislation.

The report also shows officers carried out 2,958 visits across the north in connection with food hygiene, and 826 in connection with food standards – the composition and labelling of food.

The report comes as the Food Standards Agency (FSA) has proposed a UK-wide system to grade the hygiene of restaurants, cafes, supermarkets and other food outlets.

The results would be displayed on doors or windows, as well as on a website to allow consumers to check ratings, in an effort to improve standards and cut food poisoning.

The agency believes a national scheme is needed to replace the plethora of "scores on doors", with nearly half the 435 local authorities already having or being about to introduce their own systems. In some areas, consumers and the media have had to use freedom of information legislation to find out the verdict of hygiene inspectors.