title: Emulsifying properties of the transglutaminase-treated crosslinked product between peanut protein and fish (Decapterus maruadsi) protein hydrolysates.
abstract: BACKGROUND
  Defatted peanut meal, a protein-rich by-product from the oil extraction industry, is underutilised owing to its inferior functional properties. In this study, transglutaminase (TGase) crosslinking and proteolysis were used to improve the emulsifying properties of peanut protein isolate (PPI) extracted from the meal. PPI and PPI hydrolysate (PPIH) were conjugated separately with fish (Decapterus maruadsi) protein hydrolysate (DPH), catalysed by TGase to obtain improvements in the emulsifying properties.
  
  
  RESULTS
  Analyses by electrophoresis and high-performance liquid chromatography indicated that polymers were formed in all TGase-treated samples. In emulsions of PPIH, PPI-DPH and PPIH-DPH the volume/surface average particle diameter (d(32) ), creaming and instability phenomenon were decreased and the zeta-potential was increased after TGase treatment, showing improved emulsifying activity and emulsion stability. In the case of PPI, TGase treatment had no effect on the emulsifying activity, but the emulsion stability of TGase-treated PPI was improved.
  
  
  CONCLUSIONS
  The study showed that TGase crosslinking and proteolysis could improve the emulsifying properties of PPI, while proteolysis followed by TGase crosslinking proved more efficient. The emulsifying properties of the heterologous protein systems of PPI-DPH and PPIH-DPH were also improved by TGase treatment.
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, Guangdong, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Hu
authors.forename: Jiaoyan
authors.initials: J
authors.lastname: Ren
authors.forename: Mouming
authors.initials: M
authors.lastname: Zhao
authors.forename: Chun
authors.initials: C
authors.lastname: Cui
authors.forename: Pengchen
authors.initials: P
authors.lastname: He
mesh_terms: D000818:Animals; D010367:Arachis / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000378:metabolism; D045703:Emulsifying Agents / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry; D029941:Fish Proteins / Q000737:chemistry*; D005399:Fishes; D006868:Hydrolysis; D010316:Particle Size; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism*; D011108:Polymers / Q000737:chemistry; D011492:Protein Hydrolysates / Q000737:chemistry / Q000378:metabolism*; D017368:Protein Prenylation; D012639:Seeds; D011503:Transglutaminases / Q000378:metabolism*
chemical_list: D003432:Cross-Linking Reagents; D045703:Emulsifying Agents; D004655:Emulsions; D029941:Fish Proteins; D010940:Plant Proteins; D011108:Polymers; D011492:Protein Hydrolysates; D011503:Transglutaminases