1) Acetify 2) Acidify 3) Change taste 4) Embitter 5) Make slightly sour 6) Make sour or more sour 7) Sour 8) To acidify 9) To make somewhat acid 10) To sour 11) To sour somewhat 
• (v. t.) To make sour or acid in a moderate degree; to sour somewhat.
A·cid'u·late transitive verb [ imperfect & past participle Acidulated ; present participle & verbal noun Acidulating ] [ Confer French aciduler . See Acidulous .] To make sour or acid in a moderate degree; to sour somewhat...
acidulate 1. To render more acid or sour. 2. To make somewhat acid or sour; to flavor with an acid.
to make somewhat acid. · to sour; embitter.