recipies

I’m thinking of experimenting with different acids and extracts to find a super sour enhancer... I know malic acid is used commonly so I based my reaserch on that nearly all the chemicals I want to use have a higher ph wich means they are less acidic the only exception I have found is vitamin c...

So i use FA orange and TFA orange cream and i cant find a good percentage with either of those flavors. is there any good percentages for either of these? also, are there any other good orange concentrates without diacetyl out there?