Antioxidant effects of ethanol extracts from plants on semi-dried eels

Abstract

Ethanol extracts from Ginger, cinnamon, dried onions, and Hutgae (Hovenia dulcis Thunb.) trunk were pre-treated on the eels to find out their peroxidation preventing properties on the eels. The eels were evenly coated with the extract equivalent to 2% of their total weight and dried for 15 h at 35℃ using an air blower. Antioxidative properties of ethanol extracts were reviewed through the DPPH scavenging effect, and the acid value, peroxide value, and linoleic acid value of the semi-dried eels, and also the delayed reaction of peroxidation of semi-dried eel oil. The highest level of DPPH scavenging was cinnamon extract, followed by Hutgae trunk extract, dried onions, and ginger (p<0.05). Regarding acid value of eels refrigerated for 21 days, ginger extract recorded the lowest. As in the preventative effect of free fatty acid, ginger extract prevented the early hydroperoxide during the drying process of eels. During the 20 days of peroxide-induced-reaction period, the most effective preventer of linoleic acid peroxide was Hutgae trunk extract and ginger and dried onion extracts were followed. During the 20 days of peroxide-induced-reaction period, the effective peroxidation preventers of semi-dried eel oil were ginger, cinnamon, and dried onions extracts. Hutgae trunk extract was found to delay effectively the peroxidation induction period of eel oil. In conclusion, pre-application of ethanol extracts from ginger and cinnamon was effective in delaying peroxidation of eels in the drying process and of semi-dried eels in refrigeration, and extracts from dried onions and Hutgae trunk were stalling the induced peroxidation and restricting peroxide content to some degrees.

Assessment of the Effects of Salt and Salicornia herbacea L. on Physiochemical, Nutritional, and Quality Parameters for Extending the Shelf-Life of Semi-Dried Mullets (Chelon haematocheilus)

“…Food materials containing fats and oils are acidified via auto-oxidation in the presence of oxygen and heat, thus affecting food quality [ 9 ]. Acidification is a major contributor to product deterioration, causing economic losses of more than $700 million annually [ 10 ].…”