Genipin-Aided Protein Cross-linking to Modify Structural and Rheological Properties of Emulsion-Filled Hempseed Protein Hydrogels

Qingling Wang, Jiang Jiang, Youling L. Xiong

Research output: Contribution to journalArticlepeer-review

27 Scopus citations


Genipin, a natural electrophilic cross-linker, was applied (5, 10, 20, and 30 mM) to modify hempseed protein isolate (HPI). Genipin treatments resulted in general losses of total sulfhydryls (up to 2.9 nmol/mg) and free amines (up to 77.3 nmol/mg). Surface hydrophobicity decreased by nearly 90% with 30 mM genipin, corresponding to similar tryptophan fluorescence quenching. The genipin treatment converted HPI into highly cross-linked polymers. Hydrogels formed with such polymers when also incorporated with hemp oil emulsions exhibited substantially enhanced gelling ability: up to 3.3- and 2.6-fold increases, respectively, in gel strength and gel elasticity over genipin-untreated protein. The genipin-modified composite gels also exhibited superior water-holding capacity. Microstructural analysis revealed a compact gel network filled with protein-coated oil globules that interacted intimately with the protein matrix when treated with genipin. Such gels remained readily digestible. Hence, genipin-treated hemp protein hydrogels show promise as functional food components.

Original languageEnglish
Pages (from-to)12895-12903
Number of pages9
JournalJournal of Agricultural and Food Chemistry
Issue number46
StatePublished - Nov 20 2019

Bibliographical note

Funding Information:
This work was supported by an Oversea Study Fellowship from the China Scholarship Council (to Q.W.) and the USDA National Institute of Food and Agriculture (Hatch Project 2351267000). The authors would like to thank Dr. Wenhua Xu from the Department of Pharmacology and Nutritional Sciences at the University of Kentucky for assisting with the gel structure analysis.

Publisher Copyright:
Copyright © 2019 American Chemical Society.


  • composite gel
  • cross-linking
  • genipin
  • hemp protein

ASJC Scopus subject areas

  • Chemistry (all)
  • Agricultural and Biological Sciences (all)


Dive into the research topics of 'Genipin-Aided Protein Cross-linking to Modify Structural and Rheological Properties of Emulsion-Filled Hempseed Protein Hydrogels'. Together they form a unique fingerprint.

Cite this