Delia factor; Forget about sophisticated marketing strategies . . what you need to sell more is the:.
The pulling power of Delia has sparked a run on everything from eggs to heavy-duty omelette pans. The National Farmers' Union said: "Anyone who can generate an increase in demand is an asset. Perhaps we could get her on board to recommend some of our other products."
Over the years, the Delia factor has also boosted sales of lime and coriander, liquid glucose, tahini paste, cranberry and even lemon zesters.
Delia proved a saviour to workers at an ailing frying pan company in Morecambe, Lancs. After just one mention of their omelette pan on her show, the firm was flooded with orders.
Lune Metal Products had just laid off ten of its 65-strong workforce and were about to axe the pounds 10 pan - yearly sales 200 - from their range. Then Delia called it a "little gem" on her new back-to-basics BBC cookery programme - and sparked 90,000 orders.
The company had to take on 15 extra staff to cope with the demand.
Managing director Nick White said the Delia effect was "unbelievable. Everybody has been surprised.
"The manufacturing industry is dead on its feet at the moment so it's good to see Delia doing her bit.
"She's the patron saint of the Lune frying pan!"
Delia has also been given the credit for bumping up sales of white eggs by 10 per cent. After she used white eggs, everyone wanted them instead of brown. Demand shot up by 1.3 million a day.
A spokesman for the British Egg Information Service said: "The increase in demand is directly linked to Delia's show.
"We are very impressed and think Delia is great. She has shown that eggs are healthy and versatile.
"Consumers are asking for white eggs and refuse to accept that brown are just the same. If Delia uses white, they want white."
Experts say Delia has the power to increase sales by up to 2,000 per cent. The Delia factor caused a nationwide liquid glucose shortage in 1990 when she listed it in a recipe for truffle torte.
In 1994 there was a lime and coriander crisis when they were key ingredients in her recipe book Summer Collection.
And in 1995 she caused a cranberry famine after naming the little-known berries as her "ingredient of the year" and picturing them on the cover of Winter Collection.
A simple mention of a "little lemon zester" in her Complete Cookery course caused a Europe-wide shortage.
Even lattice pastry cutters, "pop-out" flan dishes, pine nuts, pickled walnuts and miniatures of cherry brandy have been cleared from shelves after getting her blessing.
One devoted fan said: "If Delia says its good, we buy it."
Claire Murphy of Marketing magazine said: "Delia is seen as someone who is reliable and trustworthy.
"She's not just a flash in the pan."