The effect of isomerization and degradation of polyunsaturated fatty acids from oils by different volume proportions of tetramethylammonium hydroxide in thermally assisted hydrolysis and methylation

The optimum volume proportions from seven different proportional concentrations of tetramethylammonium hydroxide (TMAH) have been chosen during the analysis of soybean oil by thermally assisted hydrolysis and methylation (THM) gas chromatography (THMGC). The effects of isomerization and degradation of polyunsaturated fatty acids from oils have been observed by the alkalinity of TMAH. The optimum volume proportion of pyrolysis methylation reagent is 1:50 (TMAH:methanol, v/v, pH = 8.8).