The decreasing tendencies of active sulphydryl contents of grass carp myofibrillar protein with and without cryoprotectants during frozen storage were similar to their total sulphydryl contents
(Fig. 3B). Throughout the storage of 30 days, the active sulphydryl content of the control sample (decreased by 45.8%) reduced more rapidly than those of the samples added with KGM (decreased by
30.5%) and sucrose–sorbitol mixture (decreased by 32.2%).