Protein isolates, stability behavior

Sua J-E, Yuanb XY et al (2010) Properties stability and biodegradation behaviors of soy protein isolate/poly(vinyl alcohol) blend films. Polym Degrad Stab 95 1226-1237... 

Most interfaces encountered in food systems will contain more than one protein. Commercial materials used to stabilize emulsions or foams are complex isolates rather than purified single proteins. To describe the behavior of protein isolates it is necessary to imderstand the types of structures formed by mixtures of proteins at the interface, and also how such mixed structures are displaced by surfactants. 

Multiple regression analysis performed for succinylated rapeseed protein isolates indicated that emulsification activity was related to protein solubility, hydrophobicity, zeta potential, and flow behavior of aqueous dispersions of the proteins. Emulsion stability was affected by protein solubility, zeta potential, apparent viscosity of protein dispersions, and difference in density between aqueous and oil phases [76],... 

There are a number of useful reviews of the effects of temperature on enzyme activity, and these apply as much to reactions at 100° as at 37°. However, enzymes stable at 100° have a number of advantages as research subjects. For example, they can be used to investigate enzymes that are particularly unstable when isolated from mesophiles, to slow reactions without the use of cryosolvents, and to probe the effect of temperature on enzyme and protein behavior over a very wide temperature range. They can also be used to study enzyme behavior under conditions that would denature most enzymes, since enzymes resistant to heat are also, at room temperature, resistant to organic solvents, chaotropic agents, and proteolysis. Clearly, such stable enzymes also have a variety of applications in biotechnology, where protein stability may be an important practical and economic factor. 

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