But it was her Austrian grandfather Morris Davis who brought about much intrigue and mystery.

Born in Cobham, Surrey, on January 21, 1951, celebrity chef Rosemary always knew there was something different about her due to her "strong mid-European" personality.

She explained: "I have always been out there and larger-than-life and nobody else in the family is like me. I felt like I was a throwback.

"When my grandfather Morris died we found out he was Jewish - which none of us knew. We weren't allowed to go to the funeral because he wanted a traditional Jewish funeral."

Rosemary confessed that she would "love to know more about him and that side of the family".

She added: "The only thing we know about him was that he had something to do with umbrellas and macintoshes. I know there is still family in Manchester."

And the I'm A Celebrity, Get Me Out Of Here star's husband Michael Shrager comes from an "Orthodox Jewish background".

When I commented on the Jewishness of her grandfather's name, the daughter of June Rosemary Twentyman Davis and John Worlledge, seemed surprised.

She laughed: "Unfortunately he died 55 years ago, but he was from Austria and I believe he was brought over to Manchester and raised by a family there.

"I'm not sure of the story, but he married my grandmother who was a Yorkshire society lady and in those days it wasn't exactly clever to admit you were Jewish.

"My grandmother wasn't Jewish, but her grandmother was Jewish so it's all very confusing.

"It's weird - we have such an eclectic situation going on and I would love to do something like the BBC show Who Do You Think You Are? to find out where I stand."

She continued: "My great-great-great-great-grandmother was a very bright lady and she went to university, which was not done in those days.

"It's a very difficult timeline to work out, but I have Jewish blood running throughout it."

Rosemary admitted that, due to her husband's side of the family they often "have Passover and hot cross buns together".

She added: "We have always done Passover as well as Chanucah with our latkes etc. It is a very strong thing in our family for our children to understand their Jewish ancestry and to reflect upon it.

"I want them to be proud of it - it is their heritage and it is such a strong Jewish line."

After studying interior design, Rosemary worked for an architect in London as a "lowly technician".

She said: "We were asked if we would design the Miller Howe hotel in Windermere where chef John Tovey worked. He was one of my heroes at the time and all I wanted to do was meet him.

"I cooked all the time as a child, which came from my grandmother."

She asked to meet John, but was refused because "I was only a minion.

"So I decided to hand my notice in and went to work for a catering company on Sloan Street, London, to make lunches, although I had had no formal training whatsoever. I was learning from the book Mastering the Art of French Cooking."

The author of five books, including Castle Cook, School for Cooks and Yorkshire Breakfast, Rosemary admits she was "very lucky" to have been brought up with the knowledge of knowing about seasonal foods.

She continued: "I decided that I really didn't know much about cooking, but had to carry on. I went to work in gastro pubs to learn the craft, that was around 35 years ago.

"I was in a relationship with my husband where I didn't actually need to work, but I wanted to."

Rosemary is part of an elite list of television chefs who had had their own cookery shows - Rosemary Shrager's School for Cooks, where 10 contestants competed for the opportunity to work in a Michelin star restaurant.

But she admits that being on television was never "part of the plan".

She said: "We had moved to Cornwall and I had my own restaurant as well as working for Jean-Christophe Novelli.

"My husband and I lost everything in 2008 due to the recession. All we had was a suitcase. We lost the house, our dog, our cat . . . everything.

"I thought 'right, I'm going to bloody well get on with it'. I went to work for all sorts of people in all sorts of places - I didn't care what I did."

Rosemary was determined to "get my credibility back" and went to work for acclaimed French chef Pierre Koffman.

She recalled: "It was lovely working for him - lovely, but hard. I started off on the lowly jobs such as making bread, but eventually moved onto starters and things like that.

"At that point, I wanted to go and get another job so went to Scotland for a while and started to do television.

"That's when I did Castle Cooks and Rosemary on the Road."

She added: "If I wanted to learn how to make sausages I went to work in a butchers. Whatever I wanted to learn, I went off to a specialist to do so.

"It was the best kind of training I could have - they were specialists at their craft.

"I used to carry a notebook with me so I could write everything I had learned down. I still have it and use it to this day.

"I even went to Cornwall to learn how to make the best pasty in the world.

"It was also great for the local businesses because they could all say that I had worked there and that they were part of my journey."

Rosemary runs her own cookery school. She explained: "I started it 20 years ago after realising how lucky I was to have turned my hobby into a career.

"It began in Scotland at Amhuinnsuidhe Castle, but when the owners decided to sell it, I got a phone call from Swinton Park, Swinton, asking if I could join their cookery school.

"I was there for 10 years and now I have my own school in Tunbridge Wells where I teach everything."

Rosemary's career took a surprising turn when she made an appearance on the ITV reality show I'm A Celebrity in 2012.

"I never expected it, but I wasn't surprised because I am a bit of a one-off in my world," she explained. "My friends call me Shrager-bomber and I am what I am.

"That show was a real challenge and I loved it, but what I wasn't going to do was take over so I sat back and told everyone else what to do with the food.

"I was proud of being on it, it was such a risk, but the most important thing is to be yourself.

"You never know how these shows will be edited so you have to stay true to yourself."

After leaving the jungle, Rosemary received a positive reception, much to her surprise as she "thought everyone was going to hate me".

She did, however, admit that if she ever appeared on Celebrity Big Brother "you know they would be paying me £1 million".

Rosemary added: "My career managed me, I didn't manage it. I had to follow my heart with it so I just did the best I could.

"I have children, Tom and Kate, and I had to make sure they were alright and that I could help them, so I had to really look after myself by making sure I had work.

"What I did give up was my social life - I have lots of friends who stick with me, but I've missed weddings, funerals and more because of my work.

"I missed a lot of important moments with people I love, but I'm lucky to have friends who understand and support me in whatever I do."

The 65-year-old has started writing an autobiography while continuing with her TV career and admitted that "something was in the works and the deal is done," but couldn't divulge any more details.

She added: "I have loved working with people such as Novelli and Koffman over the years.

"They are special people and geniuses - learning, listening and taking everything in has been such a highlight."

Rosemary's advice to those looking to take up a career in food was simple - "you have to just suck everything up, work hard and get on with it.

"It is a very exciting career and you have to have the stamina and the will to make it work."

Rosemary's new series with baker John Whaite - The Chopping Block - is on every weekday (3pm) on ITV1.

If you know any details about Morris Davis, email acailler@jewishtelegraph.com