Trace metal contents, chemical properties and oxidative stability of capelin and herring oils produced in norwegian plants

• Published in: Journal of the American Oil Chemists' Society
• Main Authors: Notevarp, O., Chahine, M. H.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1972
• Subjects: Norway; Northern Norway
• Online Access: http://dx.doi.org/10.1007/bf02582592; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1007%2FBF02582592; https://onlinelibrary.wiley.com/doi/full/10.1007/BF02582592

Abstract The iron and copper contents of 14 crude capelin oils, two herring oils and one blend produced in oil meal plants in northern Norway were determined by atomic absorption spectroscopy (AAS). Their oxidative stability, peroxide (PV), benzidine (BV) and iodine values (IV), free fatty acids (FFA) and tocopherol contents were also evaluated. The oxidative stability was found to be more dependent on the tocopherol content and BV of the crude oils than on their content of trace metals. Changes in iron, copper and nickel contents were determined by AAS after refining and hydrogenation of marine oils in two Norwegian hydrogenation plants. The content of trace metals in the oils and hydrogenated products decreased as a result of alkali refining and bleaching to the lower limits of detectability by the method used, and amounted to 0.01 (oils), 0.02 and <0.3 ppm for iron, copper and nickel respectively.