Although the subject matter of Josceline Dimbleby’s two most recent books differs greatly, they are both page-turning stories that link to aspects of her life.

Her latest book, Orchards in the Oasis, is a memoir exploring the food influences of her rich and varied life.

As with the other 24 cookery books she has published over the years, it is full of delicious recipes from around the world. She was creating fusion-food long before the term fusion-food was coined, and continues to do so.

A Profound Secret, however, is not about food. It is a story of forbidden love centring on her great-grandmother May Gaskell, May’s daughter Amy Gaskell and the pre-Raphaelite artist Edward Burne-Jones.

May and Amy lived in Kiddington Hall, a late 18th-century house near Woodstock where Josceline often stayed with her grandparents when she was young.

It was a chance meeting with Andrew Lloyd Webber, owner of a haunting portrait of Amy Gaskell by Burne-Jones, that led her to investigate an intriguing family legend and then write her family history from the 1850s to the end of the Second Year War.

When she met Lloyd Webber she had no idea that she would become gripped by her research in an attempt to discover why both mother and daughter needed comfort from Burne-Jones, nor that she would uncover such a sad, romantic and mysterious story Thanks to a stash of letters stored in leather volumes and paper folders, stored in a cousin’s house, the story of May’s romance with the great painter unfolded quite rapidly. Some of these letters from Burne-Jones to May were in a leather-bound volume engraved in gold with the words: “Time will Haste and Waste, these will last.”

Josceline felt privileged to be reading them, but a little guilty too. Guilt turned to surprise when she discovered just how passionate they were. It must be remembered however, that in the Victorian era men and women who were married, but not to each other, frequently exchanged passionate letters and whispered endearments, yet their relationship remained platonic. The erotic correspondence between May and Burne-Jones began in the early spring of 1892 and continued until his death in 1898, becoming the last romantic obsession of his life.

It wasn’t long before Josceline acquired more family letters, photographs and documents from distant relatives, including a trunk of documents which simply took her breath away. She also called on photocopies of May’s notes written towards the end of her life, which were heartfelt observations of all May knew of her own family, the Melvilles, and her husband’s, the Gaskells of Kiddington Hall, during the previous two generations.

Her father had given Josceline the papers when she was younger, at a time when she was more interested in herself than the past.

Josceline admits the research was time-consuming and that she had never done anything like this in her life. “It was like being a detective,” she said, adding that it soon became so intriguing that she began to wonder what to do with the information the letters and documents were disclosing.

“At first I thought that they just warranted an article, but I was soon persuaded to write them into a book. Friends said it would probably take me five years to complete, but did it in three, even though the more I delved, the more questions emerged.”

Josceline was particularly intrigued with the photographs she managed to unearth, many of which were taken by Amy, who was an excellent photographer.

It was, however, a small dusty bundle tied with string, bearing a luggage label that thrilled her most. The label, written in May’s handwriting, said: “Paint brushes given to Helen Mary Gaskell by Edward Burne-Jones.” Josceline said her heart thumped when she undid the string to reveal the contents of this package.

She is taking part in the Oxford Literary Festival on Saturday, April 2, at noon, when she will talk about ‘Travels, Life and Memories’.

* Orchards in the Oasis is published by Quadrille at £25, A Profound Secret by Doubleday at £20.