Changes in physicochemical properties and gelation behaviour of caseinomacropeptide isolate by treatment with transglutaminase


Kilic-Akyilmaz M. , KOCAMAN E., Gülsünoğlu Z. , SAGDIC-OZTAN C., MAVAZEKHAN S. M.

INTERNATIONAL DAIRY JOURNAL, vol.84, pp.85-91, 2018 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 84
  • Publication Date: 2018
  • Doi Number: 10.1016/j.idairyj.2018.04.005
  • Title of Journal : INTERNATIONAL DAIRY JOURNAL
  • Page Numbers: pp.85-91

Abstract

The gelation behaviour of caseinomacropeptide isolate (CMPI) treated with transglutaminase at levels of 1 and 25 U g(-1) protein was investigated at different pH and temperatures. Cross-linking of CMPI protein fractions by transglutaminase was confirmed using tricine-sodium dodecylsulphate-polyacrylamide gel electrophoresis. Cross-linking reduced the isoelectric point and hydrophobicity of CMPI. The gelation temperature of CMPI at pH 3 was reduced from 54 to 42 degrees C; a gel point (G'>1 Pa) was not observed at pH 4.5 after enzyme treatment during temperature sweep measurements. Cross-linked CMPI formed a gel with lower stiffness and fracture stress at 90 degrees C at pH 3.0 or 4.5 compared with gels of untreated CMPI. However, stiffness and fracture stress of CMPI gels formed at 70 degrees C at pH 3.0 increased by three-and four-fold, respectively, by cross-linking with 25 U g(-1) protein of enzyme. Transglutaminase affected gelation of CMPI by cross-linking of both CMP and residual whey proteins. (c) 2018 Elsevier Ltd. All rights reserved.