Savoury taste of cumin, nothing extreme, captivating mother (5)
I believe the answer is:
umami
'savoury taste' is the definition.
(I've seen this before)
'cumin nothing extreme captivating mother' is the wordplay.
'nothing extreme' indicates the central letters (the letters on the extremes are removed).
'captivating' indicates putting letters inside (captivate could historically mean to hold captive).
'mother' becomes 'ma' (ma can mean mother).
The middle of 'cumin' is 'umi'.
'umi' placed around 'ma' is 'UMAMI'.
'of' is the link.
(Other definitions for umami that I've seen before include "Savoury taste sensation produced by glutamates - I, a mum (anag)" , "Savoury flavour" , "Fifth flavour" , "Newly discovered taste" , "meaty taste" .)