As we all know, the royal family follow strict eating rules in line with royal protocol, including avoiding all shellfish, steering clear of garlic and not drinking tap water when travelling abroad – but that doesn't mean the Queen and Co have to pass on trying a local delicacy!
SEE: The Queen's daily diet revealed: what the royal eats for breakfast, lunch, and dinner
On Monday, the Monarch stepped out for the first engagement of her four-day visit to Scotland, accompanied by her grandson, the Duke of Cambridge.
WATCH: Foods the royal family NEVER eat - here's why
The Queen and Prince William visited AG Barr's factory in Cumbernauld, where the iconic Irn Bru drink is manufactured.
Although whiskey is traditionally considered Scotland's national drink, Irn Bru is fondly referred to as "Scotland's other national drink", given its long history and humorous advertising that has proved to be popular amongst Scots through the years.
The Prince revealed "you can taste the girders in it" upon his first taste of Irn Bru
Sampling Scotland's iconic soft drink, the royal duo were invited to try a sip of the orange sparkling liquid, which boasts a unique flavour owed to a coveted secret recipe.
Prince William seemed to enjoy his taste of the Scottish elixir, whilst the Queen didn't try the iconic drink. Perhaps she would've preferred a cup of her finest English breakfast tea…
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After touring the plant with the Queen, the duke was offered a drink and was asked by commercial director Jonathan Kemp if he had tried Irn Bru when he was a student at the University of St Andrews in Fife.
“Not St Andrews,” he replied, but added that Irn Bru was often a part of lunches during his time in the armed forces, and after raising his glass and sipping he said it was “delicious”.
William was intrigued when Colin Reilly, upstream manager, brought over a small jar containing the clear essence of Irn Bru – with the recipe a secret only known to three people.
The Queen was all smiles for her first day in Scotland
After taking a long sniff the duke said: “I’m trying to guess what’s in it but that’s quite hard, isn’t it?”
Mr Reilly said: “I’d love to tell you,” and William smiled as he replied: “This is a closely guarded secret.”
So why the Irn-Bru factory might you ask? In Edinburgh, Glasgow and Stirling, Her Majesty is set visit businesses, charities and cultural institutions that highlight the pioneering work taking place to further community engagement, education, technology, and efforts to combat climate change.
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