Tasty fruit left out? It's rotten, one's no good (10)

I believe the answer is:

appetising

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'tasty' is the definition.
(I've seen this before)

'fruit left out? it's rotten one's no good' is the wordplay.
'fruit left out?' becomes 'appe' (I can't explain this - if you can you should believe this answer much more).
'rotten' indicates anagramming the letters.
'one' becomes 'i' (Roman numeral).
'no good' becomes 'ng' (abbreviation).
'its' anagrammed gives 'tis'.
'appe'+'tis'+'i'+'ng'='APPETISING'

Can you help me to learn more?

(Other definitions for appetising that I've seen before include "Mouth-watering" , "Tasty" .)

I've seen this clue in The Guardian.

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