Preparation of Neoglycoprotein from Carp Myofibrillar Protein by Maillard Reaction with Glucose: Biochemical Properties and Emulsifying Properties

Neoglycoprotein was prepared from carp myofibrillar protein by using the Maillard reaction with glucose, and its solubility in a high ionic strength medium, Ca-ATPase activity, and emulsifying properties were investigated. For reacting with glucose, the lyophilized protein mixed with glucose (the weight rate: 1:9) was incubated at 40 °C (for 24 h), 50 °C (for 6 h), or 60 °C (for 3 h) and 65% relative humidity. Fructosamine was produced during incubation, and available lysine content decreased simultaneously at all temperatures. In these conditions, the Maillard reaction occurring between a lysine residue and glucose was in the early stage. The glycosylated protein has high solubility in 0.5 M NaCl, and its emulsifying properties were superior to unglycosylated protein, although Ca-ATPase activity was completely lost. The regulation of the Maillard reaction in the early stage would be important for improvement of functional properties of fish myofibrillar protein.