Oil dissolved in low temperature state becomes a finely dispersed substance (7)

I believe the answer is:

colloid

'a finely dispersed substance' is the definition.
(type of substance)

'oil dissolved in low temperature state' is the wordplay.
'dissolved' is an anagram indicator.
'in' means one lot of letters goes inside another.
'low temperature state' becomes 'cold' (state of being cold).
'oil' anagrammed gives 'loi'.
'loi' going inside 'cold' is 'COLLOID'.

'becomes' acts as a link.

I've seen this clue in The Guardian.

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