Improving laccase catalyzed cross-linking of whey protein isolate and their application as emulsifiers.
Whey protein isolate (WPI) was chemically modified by vanillic acid in order to enhance its cross-linkability by laccase enzyme. Incorporation of methoxyphenol groups created reactive sites for laccase on the surface of the protein and improved the efficiency of cross-linking. The vanillic acid modified WPI (Van-WPI) was characterized using MALDI-TOF mass spectrometry, and the laccase-catalyzed cross-linking of Van-WPI was studied. Furthermore, the vanillic acid modification was compared with the conventional approach to improve laccase-catalyzed cross-linking by adding free phenolic compounds. A small extent of the vanillic acid modification significantly improved the cross-linkability of the protein and made it possible to avoid color formation in a system that is free of small phenolic compounds. Moreover, the potential application of Van-WPI as emulsifier and the effect of cross-linking on the stability of Van-WPI emulsion were investigated. The post-emulsification cross-linking by laccase was proven to enhance the storage stability of Van-WPI emulsion.
VTT Technical Research Centre of Finland , P.O. Box 1000, FI-02044 VTT, Finland.
Hairan
H
Ma
Pirkko
P
Forssell
Riitta
R
Partanen
Johanna
J
Buchert
Harry
H
Boer
D003432:Cross-Linking Reagents / Q000378:metabolism*; D045703:Emulsifying Agents / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry; D042845:Laccase / Q000378:metabolism*; D008043:Linseed Oil; D008894:Milk Proteins / Q000737:chemistry* / Q000378:metabolism*; D010316:Particle Size; D014641:Vanillic Acid / Q000737:chemistry; D014867:Water; D000067816:Whey Proteins
D003432:Cross-Linking Reagents; D045703:Emulsifying Agents; D004655:Emulsions; D008894:Milk Proteins; D000067816:Whey Proteins; D014867:Water; D008043:Linseed Oil; D042845:Laccase; D014641:Vanillic Acid