The purpose of this work was to determine the course of the
esterification reaction of hexitols and
a long chain length fatty acid at different temperatures. Sorbitol
esters of lauric acid were prepared
by the esterification of sorbitol and lauric acid (molar ratio, 1:1) in
the presence of p-toluenesulfonic
acid as a catalyst. The esterification was carried out at 140,
150, 160, and 180 °C, with and without
sorbitol cyclization, under atmospheric pressure. The reaction
course was followed by taking samples
after 15, 30, 45, 60, 90, 120, and 150 min, and determining the acid
value. The results shows that
the conversion of lauric acid is better if sorbitol is previously
cycled at all examined temperatures.
This work presents one possible solution to a problem that should
be of interest to surfactant and
carbohydrate chemists.
Keywords: Nonionic surfactants; sorbitan fatty acid esters; rate of
esterification; color of the
esterification
product
The aim of this study was the monitoring of the chemical composition of olive oil at different ripening stages to determine the appropriate harvesting time during any given crop season in the northern Adriatic region. For this purpose, from September to November, two Croatian olive cultivars (Drobnica and Buza) were taken from two different olive orchards and for the respective olive oils, prepared on a laboratory scale, the major saponifiable, unsaponifiable and phenolic compounds were determined. Based on the chemical analyses performed, the optimal harvesting time has been set in October for both cultivars. Buza had a higher oleic acid, but lower total sterols, squalene and total alkanols. Compared to the local cultivars, the studied cultivars had a high total phenolic content and antioxidant activity. The antioxidant activity and concentrations of total phenols correlated with α-tocopherol in oil samples taken during the ripening progress. Finally, trace minerals detected in Buza and Drobnica oil differed, which can be an indicator of oxidative stability and authenticity of oils.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.