The pH measurement of your wine affects your SO2 requirements.
Here is a table you can use to determine how much Free SO2 is required to adequately protect your wine from oxydation and bacterial infection, based on its pH reading. Effective protection is provided at about 0.8 mg/L molecular SO2. Maximum protection is achieved at around 2.0 mg/L molecular SO2. This is also close to the level at which SO2 can be detected by the senses.
Note: Milligrams Per Litre and Parts Per Million are effectively the same thing.
|pH reading||Minimum effective protection|
(0.8 mg/L molecular SO2)
|Maximum protection before sensing
(2 mg/L molecular SO2)