Abstract:

Trilaurin, trimyristin, tripalmitin, and tristearin heats of fusion of $\alpha$ and $\beta$ polymorphs and the heat of transition were detd. alone and in the presence of sorbitan and ethoxylated sorbitan fatty acid esters, glycerol 1-stearate, triglycerol 1-stearate, triglycerol 1-monooleate, and monoglyceride citric acid ester. The emulsifiers could affect melting of the $\alpha$ form and/or recrystn. of the $\beta$ form, depending on triglyceride chain length and emulsifier structure. All the solid emulsifiers suppressed crystn. of the higher triglycerides. The sorbitan satd. esters promoted melting of the $\alpha$ polymorph rather than transformation to the $\beta$ form, and the other surfactants had the opposite effect. Slower heating minimized the inhibition of $\beta$ crystn. of tristearin by solid emulsifiers. Emulsifiers apparently modify the kinetic character of triglyceride polymorphic transitions. [on SciFinder(R)]