真烏賊的僵直度及其魚漿成膠性之熱分析研究

Study on Rigor Mortis Progress and Gel Formation of Sepia esculenta Hoyle by Differential Scanning Calorimetry

陳莉臻(Li-Chen Chen) ； 龔鳴盛(Ming-Sheng Kong)

《宜蘭技術學報》 9期生物資源專輯 (2002/12) Pp. 1-13

https://doi.org/10.6179/nit.job.2002.09.11

摘要

本研究藉由示差掃描熱量分析技術直接觀察水產頭足類的肌肉蛋白質受熱變化情形，以了解生鮮和冷凍原料的肌肉蛋白質差異，以及製作煉製品的成膠特性。動物體死亡初期的肌肉在DSC圖譜上會出現一明顯放熱峰，可作為完全僵直的判斷指標，真烏賊（Sepia esculenta Hoyle）之圖譜放熱峰於捕獲後靜置9小時完全消失，顯示真烏賊已發生僵直。利用單離蛋白的純化技術證實真烏賊肌肉切片熱分析圖譜上，50°C及76°C的二個吸熱波峰分別為肌凝蛋白和肌動蛋白的熱變性溫度，而63°C的吸熱峰則為副肌凝蛋白的熱變性溫度。自SDS-PAGE電泳顯示單離純化的副肌凝蛋白分子量大約97kD，熱變性溫度在63°C附近。製作水產煉製品的研究方面，無鹽擂潰的機械力不會破壞真烏賊的肌肉蛋白質安定性；但加入2.5%氯化鈉擂潰後，DSC圖譜上各蛋白成分的波峰溫度降低，顯示加鹽操作會促使鹽溶性蛋白質溶出，降低熱安定性。短期凍藏方式（12週以內）不影響真烏賊肌肉蛋白質的熱穩定性，唯凍藏12週後，可能會發生蛋白質凝聚的現象。將製成的魚糕測定其穿破力、變形度、膠強度顯示製品無法表現出煉製品的質感，可能為肌肉蛋白質中存在高比例的副肌凝蛋白所致。

關鍵字

真烏賊 ； 熱分析 ； 肌肉蛋白質 ； 僵直 ； 煉製品

並列摘要

In order to understand the difference between fresh and frozen marine cephalopod muscle proteins, and the gelation property of surimi-based products, the muscle protein was analyzed by using the differential scanning calorimetry (DSC). The exothermic peak was found in animal muscle at early stage of death could be used as an indicator showing its entering rigor mortis stage. The exothermic peak of freshly harvested cuttle fish (Sepia esculenta Hoyle) disappeared after 9-hourstoring exhibited the muscle had entered the full rigor stage. Protein purification technique was used to illustrate the two exothermic peaks occurring at 50°C and 76°C represented the thermal denaturation temperature of cutlle fish myosin and actin, respectively, and the endothermic peak at 63°C was the thermal unfolding temperature of paramyosin. SDS-PAGE patterns showed the paramyosin was around 97 kD, and its thermal denaturation was around 63°C. In making surimi-based products, the stability of cuttle fish muscle protein was not affected by mechanical force in the salt free-minced process. However, endothermic peak shifted to the lower temperature in DSC profiles when 2.5% salt was added during chopping, which demonstrate that the addition of salt enforced the salt-out effect in salt-soluble-protein and reduce its thermal stability. Short period (within 12wk) storage did not affect the thermal stability of proteins, but protein aggregation was observed at 12wk frozen clusters. The gel strength, breaking force and deformation of fish cakes made from cuttle fish revealed the quality were not comparable to surimi-based products, which could be due to the high paramyosin content.

並列關鍵字

Sepia esculenta Hoyle ； thermal analysis ； muscle proteins ； rigor mortis ； surimi-based product