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Polysorbates can be separated according to their functionality and architecture by liquid chromatography on a hydrophilic interaction chromatography (HILIC) column in acetone-water mobile phases containing 90-97% acetone. The different polymer homologous series are separated according to the number of terminal hydroxy groups and elute as narrow peaks. The hydrophilic part (ethoxylates of sorbitan, isosorbide, and poly(ethyleneglycol)) and amphiphilic funtionalites (ethoxylated mono-, di-, tri-, and tetraesters) were separated by HILIC mode of high-performance liquid chromatography (HPLC). All these separated functionaities are identified and confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). This combination of HPLC and MALDI-TOF MS has been proven to be an excellent tool for the characterization of heterogenous complex samples.

The kinetics of methanolysis of sunflower oil with KOH as catalyst was investigated. The content of triglycerides, the resulting methyl esters as well as diglycerides and monoglycerides was analyzed at different times at molar ratios of methanol : sunflower oil = 3 : 1 and 3.3 : 1. At a molar ratio of 3 : 1 the kinetic order appears to be second order in the first minutes, but then the reaction rate decreases rapidly due to the formation of glycerine as a second phase, which leads to a loss of methanol and catalyst. The effect of temperature, amount of catalyst and type of vegetable oil on formation of methyl esters was examined.