Delia power

1995: There is a national cranberry shortage after she highlights the merits of the humble berry 1998: She lavishes praise on a new flour - guaranteed to take the fat and the lumps out of white sauces. It sells out 1999: There is a stampede for white eggs after they appear on the cover of Delia's latest book 2000: A North Wales sea salt company is deluged after Delia recommends its product

The frantic buying behaviour from would-be chefs has even been given an official name. "Doing a Delia" has its own entry in the Collins English Dictionary, next to separate listings for her name, "Delia power" and "a Delia dish".

It is the first time in the dictionary's 100-year history that a person's name has been listed as virtually a brand name.

A spokeswoman for Asda said the latest Delia-inspired fad had seen an increase in sales "as soon as the programme finished".

She added: "It continued throughout the following day and we're going to be watching the rest of the series carefully to see if it is repeated."

French stores may also soon feel the force of the Delia effect when she launches a series of back-to-basics cook books in the country later this year.

Since one of her most famous recipes explains how to boil an egg, the move to expand into Europe is said to have irritated some purist French cooks, who believe the English cannot teach the French anything about cooking.