The parent company of KFC have denied that a handwritten note containing what is reported to be the 11 secret herbs and spices for Colonel Sanders' deep fried chicken is authentic.

The Chicago Tribune last week published what they claim could be the recipe for KFC fried chicken.

Joe Ledington said he found a handwritten note, outlining KFC's recipe, in a scrapbook belonging to his late Aunt Claudia, the second-wife of Colonel Harland Sayers.

Mr Ledington said the scrapbook had been passed down through family members since Mrs Sander's death in 1997.

However, Yum! Brands have denied that what was published is the actual 'original recipe'.

"In the 1940s, Colonel Sanders developed the original recipe chicken to be sold at his gas station diner. At the time, the recipe was written above the door so anyone could have read it. But today, we go to great lengths to protect such a sacred blend of herbs and spices. In fact, the recipe ranks among America's most valuable trade secrets," KFC parent company Yum! told the Chicago Tribune .

"To ensure the secrecy of the recipe, KFC’s 11 herbs and spices are prepared by two different suppliers before being combined together and packaged for our restaurants."

John Young Brown Jr, a former Kentucky governor who purchased Kentucky Fried Chicken from Colonel Sanders in 1964 and turned it into a multi-million dollar brand, said he has doubts about this being the original recipe.

"People along the way have all claimed they have the recipe," Mr Brown said.

In addition to the alleged secret recipe, the scrapbook also contained photographs from her wedding, original franchise agreements and original photos from various overseas KFC restaurant openings.

He claims the handwritten recipe was found on a piece of paper tucked into an envelope inside a copy of her will.

"I don't want to get in an argument with Yum! Brands about it but... I'm pretty sure that it's pretty close to the original," Mr Ledington told the Courier-Journal .

According to the Chicago Tribune , the recipe calls for: two cups of flour, 2/3 tablespoons of salt, 1/2 tablespoon of thyme, 1/2 tablespoon of basil, 1/3 tablespoon of oregano, 1 tablespoon of celery salt, 1 tablespoon of black pepper, 1 tablespoon of dried mustard, 4 tablespoons of paprika, 2 tablespoons of garlic salt, 1 tablespoon of ground ginger and 3 tablespoons of white pepper.

After testing several batches, the Tribune believe they matched the recipe as close as they could when they added MSG to the batter mix - another claim Yum! have denied.

"All of our major menu item ingredients are listed on our website, as well as certain ingredients you would like to avoid," they said in a statement, when asked directly if they use MSG.

Mr Ledington said he is not surprised people are doubting the recipe's authenticity.

""I really didn't think about it. I didn't use my head and I certainly don't want to get sued by Yum! Brands," he said.

John Young Brown Jr, the man who purchased Kentucky Fried Chicken from Colonel Sanders and turned it into a multi-million dollar brand, has also denied the recipe's authenticity (Image: AAP)

Colonel Sanders seen enjoying a pie from iconic Sydney 24-hour retailer, Harry's Cafe De-Wheels (Image: AP Photo via AAP)