Comparison of methods for the determination of free and bound sulphur dioxide in stored British fresh sausage

Abstract

AbstractA modified spectrophotometric assay for free sulphur dioxide (SO2) in sausage recovered significantly more SO2 than an electrometric ion‐selective probe method. The former was less variable than the latter. For total SO2 estimation, the spectrophotometric method gave results which were not significantly different from the Monier‐Williams distillation technique and correlation was excellent. An ion‐selective probe method showed poor correlation with, and gave significantly different results from, the Monier‐Williams technique. By use of the spectrophotometric assay, the rate of loss of free and total SO2 from sausage was found to be related directly to temperature; high storage temperatures favoured rapid loss of SO2. Significantly more free SO2 was lost from the surface than the centre of sausage and the sampling site had no significant effect on the rate or extent of total SO2 loss.