Formation of calcium-mediated junction zones at the onset of the sol-gel transition of commercial kappa-carrageenan solutions
Nickerson, Darvesh, Paulson (2010) Formation of calcium-mediated junction zones at the onset of the sol-gel transition of commercial kappa-carrageenan solutions J Food Sci (IF: 3.4) 75(3) E153-6Abstract
Gelling temperatures of commercial kappa-carrageenan solutions were measured using dynamic oscillatory shear rheometry, in response to varying polymer (0.4% to 1.6%, w/w) and added Ca(2+) (5 to 20 mM) salts. Gelling temperatures were found to shift to higher temperatures with increased polymer and Ca(2+) concentration. The Tang model was used to estimate the number of Ca(2+)-mediated cross-links formed with kappa-carrageenan at the onset of junction zone formation. Based on this model, 6 kappa-carrageenan double helices were estimated to be cross-linked by 5 Ca(2+) ions through ionic bridging and electrostatic attraction, within a cross-linking region equivalent to one pitch of the double helix.
Links
http://www.ncbi.nlm.nih.gov/pubmed/20492288http://dx.doi.org/10.1111/j.1750-3841.2010.01519.x
