Revealed: the secret of Warhol's obsession with Campbell's soup

It is one of the most enduring icons in modern art. Yet for 40 years after it first graced one of his prints, Andy Warhol's obsession with the Campbell's soup tin confounded critics and academics alike.

Now a new TV documentary will finally lift the lid on why the image of the mass-produced tin can dominated so much of the legendary pop artist's work. Far from celebrating consumerism, as has been supposed, it claims the object held a more prosaic significance for Warhol: it reminded him of his mother Julia.

According to relatives interviewed for the programme, the painter's love of Campbell's soup stemmed from his memories of being served it daily while growing up in a Pennsylvania mining town in the 1930s. The son of impoverished Czech immigrants, he came to associate the soup with a sense of comfort and belonging otherwise missing from his dislocated background.

Warhol's curious predilection lasted well into middle age. Friends recall how the lunchtime ritual continued under the watchful gaze of his mother when she moved in with him following his father's death, while a former studio assistant remembers being invited to dine with the artist – only to be presented with a bowl of soup.

Interviewed for the Channel 4 documentary, which is being screened to commemorate the 15th anniversary of Warhol's death, his brother, Paul Warhola, said: "Mother always served Campbell's soup. She always had a good supply."

Recalling a rare invitation to lunch at Warhol's apartment in the 1980s, Benjamin Liu added: "Andy said, 'I'll make some lunch for you guys.' I thought he was playing a joke on us: he opened a can of Campbell's soup and heated it up for us."

The American art critic Arthur Danto attributed Warhol's passion to "the idea of seeing it as the embodiment of nourishment, of warmth, of comfort". He added: "I think only somebody who had a very vivid sense of the precariousness of life would have thought that way. He was pretty poor after all. They didn't necessarily know where the next meal was coming from."

Donna De Salvo, the curator of a forthcoming Warhol exhibition at Tate Modern and a former friend of the artist, said his fascination with Campbell's soup reflected his status as a child of the then emerging consumer society.

"Campbell's soup gave you the choice of a different variety of ready-made food every day," she said. "Warhol's views on food were notorious. His famous statement was that his favourite was airline food."

Along with his multiple images of Marilyn Monroe and Coca-Cola bottles, Warhol's soup tin became one of the defining motifs of the 1950s pop art era. It reached its zenith as a symbol of consumerism with the opening of his first major one-man show in Los Angeles, 32 Soup Cans, in 1962.

The influence of Warhol's mother on her son's work went deeper than his life-long passion for soup. The documentary recalls how, during his childhood, she nurtured his emerging creative talents by keeping him supplied with comics and colouring books.

'Andy Warhol: The Complete Picture' , a three-part series, starts on Channel 4 on 27 January. Warhol runs at Tate Modern 7 February to 1 April.