Evaluation of the Joslyn and McConnell quantitative methods of determining peroxidase in vegetables

Abstract

The Joslyn and McConnel quantitative methods for determination of peroxidase activity in vegetables were evaluated. Four fresh vegetables were used in the evaluation which was made on a relative basis by comparing: (1) the variance in activity which occurred between duplicate samples determined by each method; (2) the variance which occurred between the planned or theoretical percent activity and the actual percent activity found in the samples by each method. The samples determined by the Joslyn method had significantly less variance in peroxidase activity between duplicates than the samples analyzed by the McConnel method. The peroxidase activity of the samples as measured by the McConnel method had significantly less variance between the actual percent peroxidase activity found and the theoretical percent activity, than the activity of the samples as determined by the Joslyn method. The McConnel method was quicker and more simple to run than the Joslyn method.