- 學位論文
保存魚類標本之自然體色:以金魚為例
Preserving natural color of fish specimens : Taking goldfish (Carassius auratus) as an example
摘要
有關於魚體標本的保存，過去以來主要以福馬林或70%乙醇來做保存， 此方法雖然可保存魚體的型態，但無法維持魚體的自然體色，本研究以橘色金魚(Carassius auratus)作為實驗對象，並成功的保存金魚之體色。金魚呈色的主要色素為類胡蘿蔔素，此色素含有長鏈的共軛雙鍵，因此容易受到環境等因素的影響，像是，光照、溫度、酸鹼、氧化，因此要維持金魚的色澤，必須使類胡蘿蔔素處於穩定的狀態。本實驗以抗氧化劑(ascorbic acid, AA、erythorbic acid, EA、sodium sulfite, SS、sodium pyrosulfite, SP、sodium bisulfate, SB)作為穩定類胡蘿蔔素的主要配方，並以CIE L*a*b色彩空間作魚體顏色變化的判斷。色度分析結果顯示每種抗氧化劑對金魚都有一定能力的保色效果，其中又以AA效果最佳，此外將AA混合加入SP以後，發現保色效果更佳。由結果驗證添加抗氧化劑作可以有效的保存金魚的體色，並可進一步發展為保存其它魚類標本的潛力。
並列摘要
Formalin and 70% ethanol are used to preserve fish specimens for long time, since they are effective in preserving morphology; however, this method is not able to preserve the natural color. In this research, we provide a new approach to preserve the natural color of goldfish (Carassius auratus). Goldfish has bright orange color, which are mainly composed of carotenoid. This particle has long chain of conjugated double bonds thus is very unstable and susceptible to environmental factors such as light, temperature, pH and oxidation. Therefore, to stabilize carotenoid in fish body is the key step of preserving its nature color. We attempt to stabilize carotenoid by various antioxidants (ascorbic acid, erythorbic acid, sodium sulfite, sodium pyrosulfite, sodium bisulfite) and compare their abilities of preserving color. The results show that each antioxidant has different abilities to preserve color of goldfish, and the ascorbic acid is the best in our experiments. Additionally, we observe that the color preserved by mixing ascorbic acid and sodium pyrosulfite is more closely to the original one. These results suggest that antioxidants can effectively preserve the color of goldfish and also have the potential application to other fish specimens.