Juan, oddly enough, after port wine (5)
I believe the answer is:
rioja
'wine' is the definition.
(Rioja is an example)
'juan oddly enough after port' is the wordplay.
'oddly enough' means one should take alternating letters.
'after' means one lot of letters go next to another.
'port' becomes 'rio' (Rio de Janeiro is a port).
The alternating letters of 'juan' are 'ja'.
'ja' put after 'rio' is 'RIOJA'.
(Other definitions for rioja that I've seen before include "wine region" , "Wine from northern Spain" , "Spanish red wine" , "it comes from grapevine" , "Popular Spanish wine" .)