Casein materials show different digestion patterns using an in vitro gastrointestinal model and different release of glucagon-like peptide-1 by enteroendocrine GLUTag cells

Food Chem. 2019 Mar 30;277:423-431. doi: 10.1016/j.foodchem.2018.10.123. Epub 2018 Oct 31.


Physicochemical properties of casein (CN) materials manufactured using different processes are well studied; however, data on their bioaccessibility or bioactivity are limited. We compared the digestion patterns and glucagon-like peptide-1 (GLP-1)-releasing activities of micellar CN concentrate (MCC) and sodium caseinate (SCN). MCC and SCN mixed with whey protein isolate (SCN + WPI) were subjected to in vitro gastrointestinal digestion; the digestibility of MCC was higher than that of SCN + WPI, and both CN materials showed different patterns of peptides released after in vitro digestion. A comparison of GLP-1-releasing activities showed that MCC induced GLP-1 secretion to a greater extent than SCN + WPI. Candidate peptides identified from CN digesta were chemically synthesized to test their GLP-1-releasing activity. GPVRGPFPIIV identified only in the MCC digesta, could stimulate GLP-1 release. In conclusion, the digestion patterns and GLP-1-releasing activity of CN materials depend on the production process.

Keywords: Bioactive peptide; Casein material; GLUTag cells; Glucagon-like peptide-1; In vitro gastrointestinal digestion; Manufacturing process; Peptidomics; Protein digestibility.

MeSH terms

  • Animals
  • Caseins / chemistry*
  • Cell Line
  • Chemical Phenomena
  • Chromatography, Liquid
  • Digestion
  • Enteroendocrine Cells / metabolism*
  • Gastrointestinal Tract / metabolism*
  • Glucagon-Like Peptide 1 / metabolism*
  • Mice
  • Models, Biological*
  • Molecular Weight
  • Particle Size
  • Solid Phase Extraction
  • Tandem Mass Spectrometry


  • Caseins
  • Glucagon-Like Peptide 1