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

Oil glands under the zest hold limonene while the white pith holds bitter compounds. 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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Citrus aroma sits in the coloured peel, bitterness in the pith

Oil glands under the zest hold limonene while the white pith holds bitter compounds

The outer coloured layer of a citrus fruit is packed with glands of essential oil, mostly limonene, which gives the sharp fresh aroma used in baking and drinks. Beneath it the white spongy pith contains bitter flavanones and very little aroma. That is why zest is taken thinly and the pith is trimmed away.

Where this comes from

Encyclopaedia Britannica

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Tags: citrus, zest, essential oils

Citrus aroma sits in the coloured peel, bitterness in the pith: the short answers

Where does this come from, and can I check it?: Oil glands under the zest hold limonene while the white pith holds bitter compounds. 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.