Chemical Analysis of Composition of Raw Soybean Oil Deodorized Distillates by GC-MS

Abstract

Deodorizer distillate is regarded as a waste material of the edible oil industries. It has intricate nature that consists of a valuable source of bioactive and nutritive compounds including phytosterols, tocopherols and squalene that are valuable economically. In this study instead of using sample pretreatments like saponification and derivatization, (using toxic solvents and tedious labor work) which are commonly utilized in previously published papers/manuscrpits, we used ultrasonic extraction of soybean deodorizer distillated with methanol, then centrifugation and the supernatant was directly injected into the GC-MS system. Optimization of the temperature profile of the oven was done to get a baseline separation of the different distillate components including, tocopherols, sterols, squalene. According to the results the most abundant compound in soybean distillate sample was phytosterols (22.5-24.3%). While concentration ranges for squalene and tocopherol were 5.9-6% and 10-11.24%, respectively. High amount of free fatty acids (62.46%) was detected and triacylglycerol was the main glycerides of distillate. The main glycerides of soybean distillate was triglycerides (1.4%). The present study exposed that the un-saponifiable fraction of deodorizer distillate could be employed after purification in drug, food and cosmetic industry because of its considerable amount of bioactive compounds.

Keywords

• gas chromatography
• soybean oil
• sterol
• tocopherol