Where does this come from, and can I check it?

Propionibacteria ferment lactate in the warm cellar and release carbon dioxide. The figure is taken from Institute of Food Technologists, 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 2,600 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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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.

Mondo Knows Facts

Swiss cheese holes come from bacteria

Propionibacteria ferment lactate in the warm cellar and release carbon dioxide After the first weeks of ripening, Swiss style cheeses are moved to a warmer cellar where propionibacteria digest the lactate left by other cultures. The fermentation produces propionic acid, which tastes nutty, and carbon dioxide, which cannot escape the dense curd. The gas collects in weak spots and swells into the round holes known as eyes. It sits in Mondo's food collection, one of 200 facts that each trace back to the reference below.

Where this comes from

Institute of Food Technologists

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: cheese, fermentation, carbon-dioxide

Swiss cheese holes come from bacteria: the short answers

Where does this come from, and can I check it?: Propionibacteria ferment lactate in the warm cellar and release carbon dioxide. The figure is taken from Institute of Food Technologists, 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 2,600 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.