Dietary component in the main cut out (8)

I believe the answer is:

thiamine

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'dietary component' is the definition.
The definition suggests a singular noun which matches the answer.

'in the main cut out' is the wordplay.
'cut' means to remove the last letter.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'in'+'the'+'main'='inthemain'
'inthemain' with its last letter removed is 'inthemai'.
'inthemai' with letters rearranged gives 'THIAMINE'.

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(Another definition for thiamine that I've seen is " Aneurin".)

I've seen this clue in The Times.

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