sour tooth

noun2

1. •
   A liking for foods that are sour.

   • Robin and Jay Brown weren't the kind of kids to be caught with their hands in the cookie jar — they each had a sour (sometimes a half-sour) tooth, and pilfered pickles instead of desserts. — 1997
2. •
   (rare) Someone with a liking for sour foods.

   • Some "sour-tooths" prefer a sweet, non-acid fruit to an acid non-sweet one, while others do not. — 1944