Title: Quality analysis of dried cod (Gadus morhua) heads along the value chain from Iceland and Nigeria

Type:
Final project
Year of publication:
2013
Publisher:
UNU-FTP
Place of publication:
Reykjavík
Number of pages:
32
Supervisors: Sigurjon Arason
Keywords:
quality analysis; cod; Iceland; Nigeria; value chain; bleeding;

Abstract

The effect of bleeding and storage conditions on the quality of dried cod heads were determined by changes in physicochemical and nutritional properties. Dried cod heads from cods that were bled alive (BA) and bled dead (BD) were produced using the Icelandic method of geothermal energy in a drying chamber. The dried cod heads were packed in jute bags and stored in simulated storage conditions similar to that of Nigeria, 65% relative humidity at 30ºC during the day and 85% relative humidity at 20ºC at night for six weeks, storage conditions were altered at 24hours intervals. Samples of dried cod heads were taken at predefined intervals for quality analyses. The bleeding method has significant (P> 0.05) effect on the colour has the bled alive dried cod heads were whiter than the bled dead cod heads. Bleeding has no significant effect on other parameters tested but they fluctuated due to fluctuation in the storage conditions. The rehydration properties of the dried cod heads decreased as the storage period increased. The water activity, pH, moisture and protein of the dried cod heads during storage were 0.4-0.6, 6.6-7.1, 12.0%-16.5% and 54.1%-60.5% respectively. Dried cod head is a good source of protein, mineral and marine lipids rich in polyunsaturated fatty acids especially omega-3 fatty acids. Drying has no significant effect on the fatty acids profile and composition of the dried cod heads. The saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids of the dried cod heads were 28.3%, 27.7% and 37.8% of the total fatty acids respectively. The storage conditions have significant effect on the freshness and spoilage indices tested. The free fatty acids (FFA), peroxide value (PV) and total volatile basic nitrogen (TVB-N) were (30.1-36.8) g FFA/100g of lipids, (13.3-74.7) meq. /kg and 74.7-185.7mgN/100g respectively during the storage.

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