Quality of Crude Oil Extracted from Aging Walleye Pollock (Theragra chalcogramma) Byproducts

摘要

The quality of crude oil was examined as a function of the temperature and delay time between collecting and processing the fish byproducts from a commercial cannery into crude oil. Extracts from pollock byproducts stored at 6 and 15 °C for up to 4 and 10 days was examined. Longer storage of byproducts resulted in higher free fatty acid (FFA) and an increase in retinol levels in the extracted crude oils. Primary and secondary oxidation assays consisting of peroxide value and thiobarbituric acid-reactive substances increased initially with storage time on day 1 followed by an unexpected decrease with storage time. Higher storage temperature resulted in greater FFA and retinol levels, but lower oxidation products in the crude oils. The tocopherol levels decreased with storage time of the byproducts with no differences between the storage temperatures. Eicosapentaenoic acid, docosahexaenoic acid and polyunsaturated fatty acids percentage remained similar in the extracted oils with the respective storage time or temperature treatments. Keywords Crude oil - Fat soluble vitamin - Lipid oxidation - Freshness pollock byproduct