Put in case for appeal related to food processing facility (7)

I believe the answer is:

enteral

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'related to food processing facility' is the definition.
I can't tell whether this definition defines the answer.

'put in case for appeal' is the wordplay.
'put in' becomes 'enter' (I've seen this in another clue).
'case for' says to hollow out the word (remove centre letters) (the letters which encase the others are used).
'appeal' with its middle taken out is 'al'.
'enter'+'al'='ENTERAL'

Can you help me to learn more?

I've seen this clue in The Guardian.

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