Yorkshire pudding must be four inches tall, chemists rule

12 November 2008

A Yorkshire pudding isn't a Yorkshire pudding if it is less than four inches tall, says the Royal Society of Chemistry.

The Society has ruled on the acceptable dimensions of the Yorkshire pudding and is now issuing the definitive recipe.

The judgement followed an enquiry from an Englishman living in the Rockies in the USA who emailed the RSC seeking scientific advice on the chemistry of the dish following a string of kitchen flops.

Ian Lyness had contacted the RSC to get an explanation for why his attempts at cooking traditional Yorkshire puddings in Colorado had gone flat. 

In other parts of the USA Mr Lyness had successfully produced puffy, towering puddings but in the high country he had low results. 

The RSC is now checking with fellow scientists to see if cooking the famed dish in a mountain climate would lead to pressure problems.

The society, which has thousands of members working in the foods and drinks industries, including top chef Heston Blumenthal, used the query to ascertain the correct way to prepare a Yorkshire pudding, as it will soon launch a food theme for coming year.

Calls to, and from, various parts of the UK led the Royal Society of Chemistry to conclude that for a Yorkshire pudding to be judged successful it had to be no less than four inches (10 cms) in height. 

Chemical scientist and author John Emsley, of Yorkshire, claimed that people not from that county rarely produced worthy Yorkshire puddings. 

"It's in the blood and instinct of people born and raised there," said Dr Emsley.

"You can always tell from the look and taste if the cook has the right touch and it is almost pitiful to observe the stuff that comes from some southern ovens - flat, pale and soggy much of the time."

Former Cambridge academic Dr Emsley added: "I have seen many grim results from people who have tried to get their Yorkshires to rise. They frequently made gross errors. After all, cooking is chemistry in the kitchen and one has to have the correct formula, equipment and procedures. To translate the ingredients into chemical terms, these are carbohydrate + H2O + protein + NaCl + lipids." 

"Some amateurs even place the batter in the fridge first. What kind of foolish act is that?"

The RSC invited Dr Emsley to define Yorkshire pudding, by delving into the lore of his home county to produce the definitive recipe.

"It is wonderful as a starter and main course, as we all know," he said. "However, we have lost sight of it as a superb dessert to follow the main meal and we should aspire to bring it back again as a genuine pudding after many years absence." 

Next year the RSC will, as one of the lighter parts of its food campaigning, produce a leaflet on the way to make the ideal 10cm Yorkshire pudding and will push for its renaissance as a dessert.

Ian Lyness said from his home in Boulder: "I use batter mix that I pick up on my trips back to Blighty and my mum's old Pyrex dish. Perhaps the secret is to make them as she, as a true Yorkshirewoman, did. I try to follow in her steps. I do not go for the silly little ones on the plate with everything else, but a traditional, big long pudding which she always served as a separate first course with gravy before the roast beef, lamb or whatever. Coleman's English mustard is also essential accompaniment, I find. But I have been struggling badly here. On Sundays from my kitchen window here I can enjoy the sight of rearing snow-capped mountains but on my plate there are apologetic little hillocks." 

This, below, is the official recipe and the Royal Society of Chemistry would be pleased to supply more details if necessary.

The Royal Society of Chemistry Yorkshire Pudding 


Tablespoon and a half of plain flour

1 egg

Half milk, half water to make a thin batter

Half a teaspoon of salt.


Put flour in a bowl, make a well in the middle, add the egg, stir until the two are combined then start gradually adding the milk and water combining as you go.

Add the liquid until the batter is a smooth and thin consistency.

Stir in half teaspoon of salt and leave to stand for 10 minutes

Put beef dripping into Yorkshire pudding tins or into one large tin but don't use too much fat.

Put into hot oven until the fat starts to smoke.

Give the batter a final stir and pour into the tin or tins.

Place in hot oven until well risen - should take 10 to 15 minutes. 


Always serve as a separate course before the main meal and use the best gravy made from the juices of the roast joint. Yorkshire housewives served Yorkshire pudding before the meal so that they would eat less of the more expensive main course.

NB: When the batter is made it must not be placed in the fridge but be kept at room temperature

Contact and Further Information

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Royal Society of Chemistry, Burlington House, Piccadilly, London, W1J 0BA