Emerging science: onion skins a salmon preserver?
By Jerome Smail
Onion skins could be effective in extending the shelf life of fresh fish, researchers at the University of Florida have found.
Senem Guner led a team of scientists from the university's Institute of Food and Agricultural Sciences (UF/IFAS) focusing on the preservation of salmon.
First, the researchers extracted bioactive antioxidant compounds – anthocyanins and polyphenols – from onion skins by keeping them in hot water for around 80 minutes and then filtering the skin.
The skin and flesh of red and yellow onions were extracted with water mixed with ethanol and acetone at 25°C, 45°C, 65°C and 90°C. Anthocyanin and polyphenol levels and antioxidant capacity were determined after extraction. Then extract was then spread over the salmon.