Effects of galangal extract on lipid oxidation, antioxidant activity and fatty acid profiles of salted duck eggs

In the present study, we investigated the effect of galangal extract on the lipid oxidation, antioxidant activity and fatty acid composition of salted duck eggs. Three groups of salted duck eggs were comparatively assessed: salted duck egg enriched with 0.1% and 0.5% (w/v) of galangal extract and salted duck egg without galangal extract as a control. Results showed that galangal extract significantly reduced 2-thiobarbituric acid reactive substances from 1.60 mg MDA kg(-1) to 1.07 mg MDA kg(-1) and anisidine values from 67.55 to 53.64 at the end of salting time, moreover, decrease in the levels of conjugated dienes were also noticed from 0.018 to 0.007% during the salting time compared to the control group. Furthermore, galangal extract along with salting time also had significant effects on the fatty acid composition. Oleic acid, followed by palmitic acid and margaric acid, were the predominant fatty acids found in salted duck eggs supplemented with galangal extract after 14 days of salting process. Results of DPPH-scavenging activity indicated that salted duck eggs supplemented with 0.5% (w/v) galangal extract had significantly higher antioxidant activity (p < 0.05) than control at 28th day of salting. Further, analysis of electronic nose revealed that the addition of galangal extract could provide unique flavor to salted eggs during the curing process.