I haven’t found a definitive answer to this question, but I’m inclined to believe you want ascorbic and not acetic acid. My takeaway from reading is that people use way more crushed Vit C tablet than @mcw.mark recommends above. Well, Mark actually recommends Camu Camu powder, but gives Vit C as an alternative. Anyway, the minute Vit C scrapings I used (see photo below) had a big impact and more seems unnecessary and possibly that it would impact flavor.
Someone asking the same question you asked (and aso not getting a clear answer):
Someone who implies it’s one half dozen the other:
https://www.dvo.com/newsletter/weekly/2015/10-30-301/cooknart7.html
Someone indicating that acetic acid is bad for gluten strength:
dusting of vit C powder and 1 tsp diastatic barley malt powder
