碩士 / 國立高雄海洋科技大學 / 水產食品科學研究所 / 102 / Atlantic halibut (Hippoglossus hippoglossus) is the main species selled as cod fish in Taiwan. More than 75% of the total cod fish selled in Taiwan are Atlantic halibut and and its main product is fillet. The fins are the major by-priduct during the filleting process and 10% of the total fish weight. The major componsitions of the fins were water, fat, protein and ash. Their ratios in the fins were 23-33%, 54-64%, 8-10% and 3-4%, respectively. The high proportion of the total fat was unsaturated fatty acids. Thus, the fins possessed high economic value. Therefore, the aims of this study are to compare different lipid extraction methods, oil quality, fatty acid composition of the extracted halibut fins oil as well as the utilization of the extraction residue.
Several extraction methods such as boiling water, autoclave, hexane, and hexane-isopropanol (HIP) were used. The highest yield was obtained by HIP extraction (40.78%), then hexane (38.91%), autoclave (26.62%). Boiling water was just 20.62%. Oil quality characteristics of the fish oil by different processes sush as acid value (AV), peroxide value (POV), ρ-Anisidine values (ρ-AV), thiobarbituric acid (TBA) and color were different. The boiling water extraction gernerated the highest AV (1.56 mg/g), and the highest peroxide, ρ-AV, and TBA vaules was obtained from HIP (18.37 meq/kg), autoclave (3.44), and the hexane (10.71 mg/kg) extraction, respectively. The fatty acid compositions between the different extraction techniques were not significantly different (p>0.05) and the average percentage of saturated and unsaturated fatty acids was 20.23% and 76.30%, respectively. The percentage of EPA and DHA was 5.95% and 6.09%, respectively.
The oil refining procedures included degumming, neutralization and bleaching. After refinement, AV, POV, ρ-AV and TBA values were 0.01 mg/g, 7.89 meq/kg, 2.07 and 4.65 mg/kg, respectively, and lower than the non-refined oil. The percentages of saturated and unsaturated fatty acids in refined oils were 19.48% and 80.52%, respcetivley, and the EPA and DHA increased 10 to 30%. Thus, the refined Atlantic halibut oils not only improved the oils quality, but also decreased the saturated fatty acids content and increased unsaturated content.
Vitamin E was added into the refined fish oil at 0%, 0.1%, 0.5%, or 1%. After 60 day storage at at room temperature (25°C), the AV values of fish oil did not show any significant difference between different vitamin E concentrations but the POV, ρ-AV or TBA values were found to be significantly lower (p<0.05) in the fish oil samples containg 0.5% or 1% vitamin E. However, no significant difference (p>0.05) was shown between the fish oil samples containg 0.5% or 1% vitamin E.
The highest calcium content (24.70%) of extraction residues was obtained from the boiling water or autoclave methods, while calcium contents in the residues obtained from the hexane or HIP were only 4.97% and 8.18%, respectively. Thus, the residues of the boiling water and autocalve were used as an ingredient of a sanck food to increase the nutrition value.
| Identifer | oai:union.ndltd.org:TW/102NKIM0084006 |
| Date | January 2014 |
| Creators | YU, CAI YOU, 余采柔 |
| Contributors | 林家民副教授 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 112 |
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