Effects on gelation

Besides pH, other preparative variables that can affect the microstructure of a gel, and consequendy, the properties of the dried and heat-treated product iaclude water content, solvent, precursor type and concentration, and temperature (9). Of these, water content has been studied most extensively because of its large effect on gelation and its relative ease of use as a preparative variable. In general, too Httie water (less than one mole per mole of metal alkoxide) prevents gelation and too much (more than the stoichiometric amount) leads to precipitation (3,9). Other than the amount of water used, the rate at which it is added offers another level of control over gel characteristics. 

John, G., Jung, J.-H., Masuda, M. and Shimizu, T. (2004) Unsaturation effect on gelation behavior of aryl glycolipids. Langmuir, 20 (6), 2060-2065. 

The thermodynamic excluded volume effect should be also reflected as a solvent effect on gelation. That is, a more delayed gelation is expected in a good solvent than in a poor solvent this was the case in the solution polymerization of DAP in various solvents [75,76]. In this connection, Walling [3] has reported the solvent effect on the gelation in the copolymerization of MMA with EDMA, but the result was contrary to our expectations. So, we will discuss this subject in more detail later. 

Gelation rate, gel strength, and long term gel stability are the gel properties that describe gelation. As mentioned previously, there are many system variables that can affect gelation. Temperature, crosslinker properties, polymer properties, water properties, and shear all have major effects on gelation. Z.11.14.1 -19.21-, ... 

These are highly effective external lubricants for PVC, with positive effect on gelation and surface quality of finished products. Polar polyethylene waxes have a pronounced anti-sticking effect and high molecular types are suitable for transparent items. Other waxes improve pigment dispersion and permit production of highly concentrated masterbatches with better colour yield. 

The present contribution intended to study the effect of HHP on Pacific whiting surimi. Pacific whiting has high levels of proteases in the muscle tissue. These enzymes rapidly breakdown myofibrillar protein during the heat-setting of surimi, thus causing poor gel formation (Morrissey et al, 1993). Therefore, effects of HHP on proteases in surimi as well as time/pressure effects on gelation as well as total plate count, pH and color were also studied. 

S Damodaran. Refolding of thermally unfolded soy proteins during the cooling regime of the gelation process Effect on gelation. J Agric Food Chem 36 262-269 (1988). 

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