Monoglyceride coagels consist of a network of plate-like crystals and are formed from a swollen gel state (a-gel). In order to resolve the transition mechanism. coagels were prepared with monoglycerides that differ in fatty acid composition (monomyristate and palmitate/stearate. respectively). Rheology provided information on kinetics of coagel formation and the strength of the resulting crystal network. From NMR measurements. the surface-to-volume ratio, tortuosity, and dimensionality of the network were obtained. These findings were in line with qualitative and quantitative structural information obtained from CryoSEM. As a model for the behaviour-of-non-monoglyceride species. the dynamics of (perdeuterated) palmitic acid was monitored in both alpha-gels and coagels. The experimental data support a two-stage mechanism. In the first stage. two-dimensional separation of D- and L-isomers in the monoglyceride bilayers of the alpha-gel occurs. This process depends primarily on lateral diffusion rate of the inonoglycerides. Pahnitic acid can be acconiniodated in the alpha-gel bilayer, but in the coagels it is separated into relative inobile and trechanically weak function zones between the crystal plates. In the second stage of coagel forination. the crystal plates also grow in the third diniension. Both monoglyceride type and concentration detennine the kinetics ofthis process. (c) 2004 Elsevier Inc. All rights reserved.