Wine and must acidification.
Concrete tank coating.
• When using tartaric acid to reduce the pH of grape juice or wine, the pH cannot be reduced below 3.0, and the fixed acid level of the finished wine (calculated as tartaric acid) may not exceed 9.0 grams per liter.
USA Regulation 27 CFR 24.246 and 27 CFR 24.182
To correct natural acid deficiencies in certain juice or wine: may not increase the fixed acid level of the finished wine (calculated as tartaric acid) above 9.0 grams per liter.