The Queen once found a slug in her dinner

According to former royal servant Charles Oliver, the Queen and Prince Philip have a notebook which they take to every meal, the Express reports.

In it, they can provide feedback for the Palace chefs.

Oliver wrote in his book Dinner at Buckingham Palace: "Mostly, the book remains blank, as the Queen is not fussy about food.

"However, when she has a guest to an informal lunch and they reveal definite likes and dislikes—such as an objection to fried potatoes or Brussels sprouts—the Queen will make a discreet note for future reference.

"This is duly recorded by the kitchen and remembered, should the guest come again."

"Once, on a torn-off top sheet the footmen found the dead body of a slug."

Beside it, she wrote: "I found this in the salad—could you eat it?"