Evaluation and stabilization of wheat germ and its oil characteristics

الملخص EN

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.