Stopping short of glycerides and salt, change excitedly (3,2,1,7)

I believe the answer is:

all of a twitter

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

'of glycerides and salt change excitedly' is the wordplay.
I cannot quite understand how this works, but
'of' could be 'o' and 'o' is located in the answer.
'change' could be 'fat' (fatting is a kind of changing) and 'fat' is present in the answer.
This explanation may well be incorrect...

'short' acts as a link.

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I've seen this clue in The Telegraph.

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