title: Wet cross-linking gliadin fibers with citric acid and a quantitative relationship between cross-linking conditions and mechanical properties.
abstract: This paper reports the wet cross-linking of gliadin fibers using citric acid without using phosphorus-containing catalysts or high temperatures. Carboxylic acids such as citric acid are inexpensive and nontoxic chemicals preferred for cross-linking proteins and cellulose. However, previous studies have shown that carboxylic acid cross-linked materials experience substantial strength loss and/or yellowing when cross-linked using phosphorus-containing catalysts after drying and curing at high temperatures. In this research, citric acid has been used to cross-link gliadin fibers and the effects of various cross-linking conditions on the breaking tenacity and breaking elongation have been studied. A mathematical relationship that can predict the breaking tenacity of the fibers at various cross-linking conditions has also been developed. This research shows that citric acid in aqueous solutions can cross-link gliadin fibers at low temperatures using alkali as catalyst. The method of cross-linking developed in this research could be useful to cross-link plant proteins for food, fiber, and other applications.
authors.affiliation: Department of Textiles, Nebraska Center for Materials and Nanoscience 234, University of NebraskaLincoln, Lincoln, Nebraska 68583-0802, USA.
authors.forename: Narendra
authors.initials: N
authors.lastname: Reddy
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Yiqi
authors.initials: Y
authors.lastname: Yang
mesh_terms: D019343:Citric Acid / Q000737:chemistry*; D003432:Cross-Linking Reagents; D004591:Electrophoresis, Polyacrylamide Gel; D005903:Gliadin / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors
chemical_list: D003432:Cross-Linking Reagents; D019343:Citric Acid; D005903:Gliadin