They've cracked it: Delia was right after all about how to boil an egg

It is a question which has divided the culinary world and prompted more than the occasional grumble at the breakfast table: how long is too long to boil an egg?

Now a group of schoolgirls believe they have finally found the answer after a series of experiments, backed by no less a scientific authority than the Royal Society of Chemistry.

They concluded that the optimum cooking time for a soft boiled egg suitable for dunking toast soldiers in is a full six minutes.

It proves that Delia Smith, the television chef, was right all along.

[Relevant: British woman makes amazing egg discovery]

She prompted some controversy in the nation’s kitchens by advocating leaving eggs in gently boiling water for six minutes without fear of the “cardinal sin” of overboiling.

Jean-Christophe Novelli, the Michelin-starred chef, is on record as advocating a mere three minutes boiling time.

Meanwhile Mrs Beeton, the Victorian authority on all matters domestic, lays down strict instructions for no more than three and a quarter minutes.

But a group of sixth form pupils at Sherborne Girls school in Dorset, backed Delia after carrying out a series of experiments in their school laboratories overseen by Prof Hal Sosabowski, a lecturer at Brighton University under the auspices of the Royal Society of Chemistry.

The knack , they found, was to get the water just to boiling point before gently dropping the eggs in and leaving then for six minutes.

The method requires large sized eggs which have been stored at room temperature before boiling.

Prof Sosabowski said: “I was particularly impressed by the pupils’ diligence in generating results but not believing what they saw upon first inspection; checking and rechecking their results; scrutinising their own experimental design to eliminate variables and error.”

Having successfully navigated the controversy over egg boiling times, the girls then moved on to a potentially even more vexed issue: what makes the best toast soldiers.

They concluded – against the prescriptions of nutritionists – that white bread is better than brown for the purpose.

They also found that margarine makes stronger soldiers than traditional butter, that the optimum toasting time for soldiers is two and half minutes and that they should be sliced no wider than 1.5cm (0.59in).

Rosanna Younger, 17, said she had been surprised by the results.

“I love butter on my toast but I might just have to swap over to margarine in future to ensure strong soldiers,” she remarked.

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