Aqueous copper sulfate solution (CuSO4 l 5H2O).
• 2 mL/hL to 10 mL/hL (10 mL/hL releases 0,64 mg/L of copper).
USA Regulation 27 CFR 24.246
The quantity of copper sulfate (calculated as copper) added to wine must not exceed 6 ppm (6mg/L). The residual level of copper in the finished wine must not exceed 0.5 ppm (0.5 mg/L).2