Analysis for total sulfite in foods by using rapid distillation followed by redox titration

J Assoc Off Anal Chem. 1986 Sep-Oct;69(5):827-30.

Abstract

A rapid and accurate analysis for total sulfite as sulfur dioxide has been developed for foods and food products. The method, which combines a selective distillation cleanup procedure with the selective redox titration of sulfite ion by iodine, has been applied to a variety of foods and food products over a period of time with no significant interference encountered in any matrixes other than garlic and leeks. For the foods analyzed, the method typically shows a detection limit of 10 ppm, a relative standard deviation of 7.5% (compared with 10.4% for similar matrixes by the Monier-Williams method), and recoveries of 97.9 +/- 6.4%. Comparison of results for this method with those obtained using the Monier-Williams method showed a mean value for the distillation/titration method of 241 ppm compared with 242 ppm for the Monier-Williams method. A correlation of 0.991 and odds of a difference between methods of 10.7% (Student's paired t-test (1-alpha) X 100) were obtained for those matrixes where no interferences were encountered with either method.

MeSH terms

  • Food Additives / analysis*
  • Food Analysis
  • Indicators and Reagents
  • Methods
  • Oxidation-Reduction
  • Sulfites / analysis*

Substances

  • Food Additives
  • Indicators and Reagents
  • Sulfites