Gelation properties and the improvement of water soluble protein from fish

2003 Fiscal Year Final Research Report Summary

• Project/Area Number: 14580161
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 食生活
• Research Institution: Nihon University Junior College
• Principal Investigator: OHTA Naoko Junior College, Nihon University, Associate Professor, 食物栄養学科, 助教授 (00203795)
• Project Period (FY): 2002 – 2003
• Keywords: water soluble protein from fish / ovalbumin / gel / fatty acid salt / dynamic viscoelasticity / fourier transform infrared spectroscopy / protein secondary structure

Research Abstract

Sodium caprate-induced gelation was investigated for water-soluble protein concentrate(WSPC) from fish with or without ovalbumin(OVA). Prior to the gel formation, effects of sodium oleate on the viscoelasticity of water-soluble protein(WSP) suspension were investigated. It was indicated that hydrogen bondings facilitated increase in dynamic modulus. Rheological measurements using WSPC indicated that although WSPC alone could not form a gel by the addition of sodium caprate, it formed a gel by the mixing with OVA even at room temperature. The WSPC-OVA mixed gel containing sodium caprate had fine microstructure which was comparable to that of fatty acid-induced OVA gel. Aggregation bands due to intermolecular β-sheet with concomitant formation of sodium caprate-induced OVA gel appeared on FT-IR analysis. However, secondary structural changes of the mixed gel from WSPC and OVA was not clear, since remarkable aggregation band in the mixed protein was not found. Further study is necessary to clarify the mechanism for formation of the mixed gel.