農業部-水產試驗所全球資訊網農業部-水產試驗所全球資訊網

冷凍秋刀魚經解凍、鹽漬、煙燻處理加工成燻秋刀魚。鹽漬時，秋刀魚分為三種前處理型態，一為全魚 (去鰓)，二為半處理魚 (去鰓及內臟)，三為背開魚片。不論何種型態，也不論浸泡於5 %，10 % 或 15 % 食鹽溶液中，魚肉的食鹽含量均於第一天急速上升，隨後則趨緩。鹽漬時，魚肉的pH無顯著變化，揮發性鹽基態氮 (volatile basic nitrogen, VBN) 下降，硫巴比妥酸價 (2-thiobarbituric acid value, TBA value) 上升；好氣性生菌數，嗜冷菌菌數，大腸桿菌群及大腸桿菌均無增加。鹽漬條件係採用半處理魚型態原料浸泡於10%食鹽溶液中，於5 °C靜置1天，後續煙燻處理使用兩組方式，一組於65 °C蒸燻 (100 % RH) 15 min，再於72 °C，40 % RH煙燻15 ~ 45 min (HHS)；另一組於65 °C，40 % RH煙燻15 min，後續於72 °C，40 % RH繼續煙燻15 ~ 45 min (LHS)。煙燻期間，兩組魚肉的水分含量均顯著下降，pH和VBN無顯著變化，TBA價則顯著增加。煙燻後秋刀魚腹部表皮L* 值下降，a* 值和 b* 值增加，呈現黃褐色；肉質的硬度和凝集性顯著增加，微生物無檢出；成品的官能品評結果，除了外觀外，風味、質地和接受性均無顯著差異 (p > 0.05)。綜合各項結果顯示，燻秋刀魚的適宜煙燻條件為在65 °C，40 % RH煙燻15 min，再於72 °C，40 % RH煙燻30 min。

Frozen Pacific saury (Cololabis saira) were thawed, brined, and smoked. Raw fish were pretreated with three treatments including round (gilled), semi-dressed, and semi-dressed and split from the back. The samples were soaked in 5%, 10%, or 15% brine for 2 d at 5 °C. The NaCl content of the flesh significantly increased on the first day, and thereafter continued to slowly increase. During the brining process, the pH value of the flesh remained unchanged; however volatile basic nitrogen (VBN) decreased, and the 2-thiobarbituric acid (TBA) value increased. This shows that there was little change in the aerobic plate counts (APCs), psychrophilic plate counts (PPCs), coliforms, and Escherichia coli during brining.The semi-dressed fish were immersed in 10% brine at 5 °C for 1 d, and then smoked. The smoking process included two methods: steam smoking (100% RH) at 65 °C for 15 min followed by smoking at 72 °C and 40% RH for 15~45 min (HHS); and smoking at 65 °C and 40% RH for 15 min followed by smoking at 72 °C and 40% RH for 15~45 min (LHS). During the smoking process, the moisture contents of both samples decreased, while the pH and VBN remained almost constant, and the TBA value increased. The L* value of the ventral skin of smoked Pacific saury decreased, while the a* and b* values increased. The appearance turned yellowish-brown after smoking. The toughness and cohesiveness of the flesh of smoked Pacific saury increased. Neither APC, PPC, coliforms, nor E. coli were detected. With the exception of the appearance, the flavor, texture, and acceptability of both products did not significantly differ (p > 0.05) according to the results of a sensory evaluation. These results show that the suitable smoking conditions for smoked Pacific saury are smoking at 65 °C and 40% RH for 15 min followed by smoking at 72 °C and 40% RH for 30 min.