ISO 5522:1981

Fruits, vegetables and derived products — Determination of total sulphur dioxide content

The method consists in acidifying and heating a test portion, entraining, in a current of nitrogen, the gas liberated, absorbing and oxidizing the gas by bubbling it through a neutral, dilute hydrogen peroxide solution, then determining the sulphuric acid thus formed using standard volumetric sodium hydroxide solution. Verification of the determination is described in the annexes A and B, respectively.