Qualitative characteristics of fat fraction of oats based products

Oat products are often chosen by people leading a healthy lifestyle for their health-promoting properties. Oats and oats based products are characterized by a higher fat content with a favorable fatty acid composition compared to other cereals. It is of great importance to control the quality of fat fraction as an important indicator of food products safety. In this study fat isolated from oats products such as: whole grain oatmeal, mountain oatmeal, instant oatmeal was analyzed. In the fat tested, the composition of fatty acids by gas chromatography; distribution of fatty acids in the internal and external positions of triacylglycerols by the method based on the ability of the pancreatic lipase to selectively hydrolyze ester bonds in the sn-1,3 positions were determined. The oxidative stability of the tested fat was evaluated using pressure differential scanning calorimetry. The induction time as a primary parameter of the resistance of fats to their oxidative decomposition was defined. Melting profiles of the analyzed fat were determined by differential scanning calorimetry.

Based on the conducted research, it was found that fat isolated from the examined oat products is a rich source of unsaturated fatty acids. In sn-2 position of triacylglycerols, the highest share of oleic acid was found. The fat isolated from the tested products was characterized by the highest proportion of linoleic acid in the sn-1,3 positions of the triacylglycerols. It was also observed that the induction time of oxidation of fat isolated from oats products, reached the values of 28.79 min - 39.07 min in the test conducted at 120°C and 5.84 min – 7.37 min. - at 140°C. In the course of the melting curves of fat, two distinct endothermic peaks were found. The analyzed melting profiles showed the presence of peaks indicating the presence of low-melting fat fractions in the isolated fat, rich in polyunsaturated and monounsaturated fatty acids.