Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 28, 2007
Publication Date: May 13, 2007
Citation: Qi, P.X., Tomasula, P.M. 2007. Characterization of caseins crosslinked by a naturally occurring crosslinking agent-genipin. (abstract). 98th AOCS Ann Mtg & Expo. p. 139. Technical Abstract: Increasing economic and environmental pressures demand more effective utilization of natural resources. Genipin, a naturally occurring crosslinking agent obtained from the fruit of Gardenia jasminoides, has recently attracted much attention due to its low cytotoxicity compared to traditional crosslinking agents such as glutaraldehyde. In this study, we examined the use of genipin as a crosslinking agent for casein-based polymeric networks using various caseins. Crosslinking reactions between casein obtained by pressurized carbon dioxide (CO2) precipitation and genipin were studied in comparison with commercially available casein products, sodium caseinate and calcium caseinate. The reactions were followed and products were examined by spectroscopic and microscopic techniques including UV-VIS, circular dichroism (CD), FTIR, Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The results showed that the rate of crosslinking reactions, in general, increased as a function of temperature and pH and suggest that the crosslinking occurs mainly between dimerized genipin and the sidechains of some basic amino acid residues of caseins. CO2-derived casein appears to crosslink with genipin more effectively than other caseins under identical experimental conditions. The possible reaction mechanism of casein crosslinked by genipin will be discussed and the significance of the successful fabrication of the casein-based polymeric network will be explored.