冻藏温度对海鲈鱼鱼糜蛋白生化指标及其凝胶特性的影响

Effect of Storage Temperature on Biochemical Indicators and Gel Properties of Sea Bass Surimi

为了研究不同冻藏温度下鱼糜品质的变化,以无添加剂的海鲈鱼鱼糜为原料,研究3种不同冻藏温度在6周时间内对鱼糜的理化特性和流变特性的影响。结果表明:随着冻藏时间延长,鱼糜的盐溶蛋白含量、Ca2+-ATPase活性、总巯基含量、保水性、白度值和凝胶强度均呈下降趋势,而挥发性盐基氮(TVB-N)含量呈上升趋势,各指标数值在4周以后进入稳定期,变化减少。在不同冻藏温度下的鲈鱼蛋白变性速率差异显著(p<0.01),冻藏温度越低,蛋白变性速率越慢,并对鱼糜的微观结构进行观察,阐释其机理。鱼糜在-24℃以下冻藏效果较好,冻藏6周后鱼糜还处于一般鲜度以上。鱼糜的机械模量(G’和G’’)随冻藏时间延长而下降,且随冻藏温度的升高其变化也越明显。无添加剂的海鲈鱼鱼糜在-24℃以下储藏6周之内可有效延缓其品质的劣变。

Additive-free sea bass surimi was used as a raw material to study the effects of three different low temperatures on the physicochemical and rheological properties of fish surimi during six weeks of storage. The results showed that the salt-soluble protein content, Ca2＋-ATPase activity, total sulfhydryl content, water-binding ability, whiteness, and gel strength were decreased with increasing storage time, but the value of total volatile basic nitrogen（TVB-N） showed an upward trend. All quality indicator indices were stable after four weeks of storage. Different storage temperatures caused significant differences in the protein denaturation rate（p〈 0.01）; the lower the temperature of chilled storage, the slower the rate of denaturation of proteins. The microstructure of surimi was observed and the underlying mechanism of slowed denaturation was explained. Storage of surimi below-24 ℃ was optimal, yielding above-average freshness after six weeks of storage. The mechanical modulus（G＇ and G＇） of surimi decreased with increasing storage time, and showed significant changes with increased storage temperature. The results showed that within six weeks, storage of sea bass surimi below-24 ℃ can effectively delay deteriorations in its quality.