Influence of Konjac oligo-glucomannan as cryoprotectant on physicochemical and structural properties of silver carp surimi during fluctuated frozen storage

The aim of this study was to analyze the effect of Kanjoc oligo-glucomannan (KOG) on functional and structural changes in silver carp surimi during fluctuated (FLUC) frozen storage. During this study, KOG was prepared and added 1 and 3% in surimi and myofibrillar protein (MP) and compared with a positive control (PC) of sucrose and sorbitol mixture added samples. The results showed that the water holding capacity (WHC), textural and structural properties decreased during FLUC-I and FLUC-II, indicating that it could be due to protein denaturation induced by the formation of irregular crystallizations and recrystallization. Moreover, it was noted that the addition of KOG (3%) enhanced the stability of alpha-helix content (58-47%) during FLUC-I and (60-50%) during FLUC-II by inhibiting the hydrophobic residue exposure and change in aromatic amino acids. Meanwhile, KOG (3%) enhanced the textural properties by inhibiting the freeze induced protein denaturation. During FLUC frozen storage, the KOG (3%) was found to be a more effective concentration than conventional cryoprotectant mixture (PC). At industrial level, KOG (3%) could be used as a potential alternative to conventional cryoprotectants to attain prolonged commercial and economic values of silver carp.