Determination of free (pH 2.2) sulfite in wines by flow injection analysis: collaborative study.
A method for the determination of free sulfite in wine by flow injection analysis (FIA) is described. The method involves liberation of sulfur dioxide from the wine at pH 2.2, with detection by decolorization of a malachite green solution. The method was collaboratively studied, and the results indicated an average reproducibility of 12% for white wine samples (average level 12.1 ppm SO2) and 26% for red wine samples (average level 3.1 ppm). When the FIA method was compared to an aeration/oxidation method, the results indicated a high degree of correlation between the 2 methods. The FIA method has been adopted by AOAC official first action.
Sullivan
J J
JJ
U.S. Food and Drug Administration, Seafood Products Research Center, Bothell, WA 98041-3012.
Hollingworth
T A
TA
Wekell
M M
MM
Meo
V A
VA
Etemad-Moghadam
A
A
Phillips
J G
JG
Gump
B H
BH
D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D013447:Sulfites / Q000032:analysis*; D014920:Wine / Q000032:analysis*
D007202:Indicators and Reagents; D013447:Sulfites