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Water in the butter vaporises and lifts the layers apart. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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Yes. It sits on the Food shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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Mondo Knows Facts

Puff pastry rises on its own steam

Water in the butter vaporises and lifts the layers apart

Unlike a yeast dough, puff pastry contains no leavening. The rise comes entirely from water in the butter turning to steam between the sheets of dough as the pastry hits a hot oven. The fat also sets the layers before they can collapse, which is why the pastry must stay cold until it goes in.

Where this comes from

Encyclopaedia Britannica

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: pastry, baking, steam

Puff pastry rises on its own steam: the short answers

Where does this come from, and can I check it?: Water in the butter vaporises and lifts the layers apart. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a food fact?: Yes. It sits on the Food shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.