Spilt leaving tram, sour condiment (4,7)

I believe the answer is:

malt vinegar

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'sour condiment' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'spilt leaving tram' is the wordplay.
'spilt' indicates anagramming the letters.
'leaving'+'tram'='leavingtram'
'leavingtram' anagrammed gives 'MALT VINEGAR'.

Can you help me to learn more?

(Other definitions for malt vinegar that I've seen before include "Acidic condiment" , "Condiment used on chips" .)

I've seen this clue in The Telegraph.

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