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The objectives of the present work were (a) to extract the phenolic fraction from the peels of two Danish varieties of potatoes, viz. Sava and Bintje, and examine their antioxidant capacity in in-vitro systems (b) to evaluate the effect of these extracts on the storage stability of a fishrapeseed oil mixture and oil-in-water emulsions. Multiple antioxidant activity of the potato peel extracts was evident from in-vitro systems as they showed strong reducing power, radical scavenging ability, ferrous ion chelating activity and prevented oxidation in a liposome model system. The Sava variety, which showed strong antioxidant activity in in-vitro systems, was tested in oil and oil-inwater emulsions. Ethanolic extracts of Sava (C1,600 mg/ kg) prevented lipid oxidation in emulsions and in oil. Water extracts showed no antioxidant activity in oil whereas it showed pro-oxidant activity in emulsions. Thus, the results of the present study show the possibility of utilizing waste potato peel as a promising source of natural antioxidants for retarding lipid oxidation.

Fucoxanthin, a nonprovitamin A carotenoid, is a yellowish‐brown pigment found abundantly in brown algae. Along with chlorophyll a, it is bound to proteins and acts as a light‐harvesting and a light‐transferring pigment. The occurrence of carotenoids and chlorophylls in photosynthetic tissues complicates the isolation of pure fucoxanthin. The present study deals with a method for the isolation of fucoxanthin by low‐temperature crystallization and testing its antioxidant activity both in in vitro assays and in 5% oil‐in‐water emulsion. The yield of fucoxanthin obtained with this method ranged from 0.1% to 0.5% of dried algae depending on the species. Fucoxanthin showed good α,α‐diphenyl‐β‐picrylhydrazyl radical‐scavenging and iron‐chelating properties. However, it showed low reducing power and was poor in the inhibition of lipid oxidation in a liposome model system. When tested in 5% fish oil‐in‐water emulsion with iron as an oxidation inducer, fucoxanthin showed antioxidant activity by resulting in low levels of volatile oxidation products and low tocopherol loss compared to control and butylated hydroxytoluene.

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