Cream and fish for preservation (8)

I believe the answer is:

pickling

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'cream and fish for preservation' is the definition.
I can't tell whether this defines the answer.

'cream and fish' is the wordplay.
'cream' becomes 'pick' ('pick' can be a synonym of 'cream').
'and' says to put letters next to each other.
'fish' becomes 'ling' (ling is a kind of fish).
'pick'+'ling'='PICKLING'

Can you help me to learn more?

I've seen this clue in The Telegraph.

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