As beer gut wobbles, something sweet in that (5,4)
I believe the answer is:
sugar beet
'something sweet in that' is the definition.
(type of beet containing sugar)
'as beer gut wobbles' is the wordplay.
'wobbles' indicates an anagram (I've seen 'wobbling' mean this).
'as'+'beer'+'gut'='asbeergut'
'asbeergut' with letters rearranged gives 'SUGAR-BEET'.
(Other definitions for sugar beet that I've seen before include "foodstuff" , "It produces sweetener" .)