Evaluation and Stabilization of Wheat Germ and Its Oil Characteristics

Wheat germ (WG) was analysed for its proximate composition, amino acids and minerals. Physico-chemical
parameters, lipid classes and fatty acid composition of wheat germ oil (WGO) were also determined. Wheat germ
was subjected to different heat treatments in order to inactivate lipase. The results showed that WG contains high levels
of protein (34.92%). Crude ether extract, crude fibers, and ash contents were 10.74, 4.89 and 5.17%, respectively.
The most abundant minerals (mg/100g) were: Potassium (1567.6) and phosphorus (389.5). Moreover, wheat germ
showed to be a good source for essential amino acids (35.81g/100g protein). Saponification, iodine and peroxide
values of the WGO were 182.94, 112.54 and 0.35 (mEq O2/kg), respectively. Also, the free fatty acids (as % oleic
acid) and the unsaponifiable matters were 2.39% and 1.92%, respectively. The wheat germ oil was found to be an
incredible source of ω3 and ω6 essential fatty acids. Furthermore, the unsaturated fatty acids represent around 80%
of the total fatty acids. A slight difference was observed in the fatty acid composition before and after lipase inactivation.
The TLC technique for lipid classes showed that the triacylglycerols fraction was considered as the major
fraction. Also, phosphatidyl inositol, phosphatidyl choline and phosphatidyl ethanol amine were the major fractions
of wheat germ phospholipids. The results also showed that the sample subjected to a heat treatment (100°C/ 30min)
before storing at –18°C was more efficient to inactivate the enzyme activity as compared to the other four samples
stored at different conditions.