Effect of Garlic Oil on Lipid Oxidation, Fatty Acid Profiles and Microstructure of Salted Duck Eggs

Abstract

Lipid oxidation, fatty acid profile and microstructure of duck egg supplemented with garlic oil were monitored over the salting period. The antioxidant activity of garlic oil was measured by 1,1-diphenyl-1-picrylhydrazyl (DPPH) assay and its activity was compared to that of standard synthetic antioxidants (butylated hydroxyl toluene and gallic acid). The scavenging percentage of garlic oil increased in a dose-dependent manner. The supplementation of garlic oil altered the characteristics of duck egg during salting. In addition, oil exudation by yolk and lipid oxidation (thiobarbituric acid reactive substances) showed an increasing trend concomitant with salting time. Microstructure observation revealed comparatively loose shell membrane structure in duck egg supplemented with garlic oil, which facilitates the transportation of oil toward the yolk. These findings contribute to a better understanding that garlic oil can be used as a potential antioxidant agent and a healthy natural food additive. Practical Applications Preservation of duck eggs by salting can maintain their quality and extend the storage period, but lipid oxidation should be prevented or minimized to assure their quality and fatty acid stability during storage. Using garlic can significantly decrease the total cholesterol, low-density lipoprotein and very-low-density lipoprotein, and increase the level of high-density lipoprotein in serum and is recommended as a dietary supplement and natural food additive. The use of garlic oil to treat salted duck eggs showed positive effects on their lipid oxidation and microstructural properties.