The best replacement for citric acid is ascorbic acid.

The best alternatives to citric acid are rated as following:
★★★★★  ascorbic acid
★★★★  lemon juice
★★★  phosphoric acid
★★★  white vinigar
★★  acetic acid
★★  vinegar
★★  vitamin c
★★  tartaric acid
★★  krebs cycle
★  citrate
★  sodium citrate
★  oxalic acid
★  fruit fresh
★  sour salt
★  citrus
★  lactic acid
  malic acid
  cream of tartar
  edta

Your alternative for citric acid is not listed? Suggest!
Speaking about citric acid, one probably shouldn't forget about sodium hydrogen carbonate.

Other search terms related to citric acid and their ratings are:
★★★★★ sodium hydrogen carbonate
★★ sodium citrate
★★ sodium bicarbonate
★ sodium benzoate
You have in mind a companion for citric acid and it is not yet here? Propose!



Google Trends

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citric acid
ascorbic acid
lemon juice