Determination of cyclamate in soft drinks by reaction with nitrous acid. Part III. Manual and semi-automated methods: determination of excess of nitrous acid with safranine

Abstract

The determination of cyclamate in soft drinks at a concentration of approximately 1 mg ml^–1 is described. Excess of nitrous acid is added to the sample and unconsumed nitrous acid is determined colorimetrically with safranine. Factors that affect the sensitivity of the latter reaction and interference due to other components of soft drinks have been investigated. Preliminary precipitation with zinc hexacyanoferrate(II) effectively reduces this interference.