Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV 26506-6108, USA.
J Food Sci. 2012 Jan;77(1):S77-83. doi: 10.1111/j.1750-3841.2011.02512.x.
The nutrient and energy demand of sexual maturation in many fish cultivars causes structural change to key contractile proteins and thereby, affects fillet firmness. Thermal denaturation and viscoelastic properties of white muscle from diploid (2N; fertile) and triploid (3N; sterile) female rainbow trout were investigated at 6 age endpoints from July 2008 through spawning in March 2009. Differential scanning calorimetry showed, in March, that the actin denaturation temperature (T(max,actin)) of 2N females was higher than that observed in 3N females (78.17 versus 77.27 °C). From 35 to 45 °C, viscoelastic measurement revealed that muscle from 2N females and younger fish (July, 16 mo) had greater elasticity (lower tan δ) than muscle from 3N females and older fish (November to March; 20 to 24 mo), respectively. The highest elastic response and the firmest fillets were observed in July. Raw fillets were softer (Allo-Kramer shear; P < 0.05) from September to January (288.77 g/g on average) than those collected in July (475.15 g/g) and March (366.79 g/g). Soft fillets became firmer after cooking except for January samples. Greater cook yield and softer fillets were observed in January compared to December. Lipid accumulation in 3N females may lubricate muscle fibers and protect them from losing functionality during the spawning season for animals on a high plane of nutrition.
The relationship between fish maturation, measured as egg development, and chemical characteristics of fillets from fertile and sterile fish was evaluated. Thermal denaturation and viscoelastic characterization revealed changes in stability and gelling properties of muscle proteins that were related to changes in fillet texture.
许多鱼类品种的性成熟需要营养和能量，这会导致关键收缩蛋白的结构发生变化，从而影响鱼片的坚实度。本研究调查了 2008 年 7 月至 2009 年 3 月产卵期间，6 个年龄阶段的二倍体（2N；可育）和三倍体（3N；不育）雌虹鳟鱼白色肌肉的热变性和黏弹性特性。差示扫描量热法显示，3 月时，2N 雌鱼肌动蛋白的变性温度（T(max,actin)）高于 3N 雌鱼（78.17 对 77.27°C）。在 35 至 45°C 的范围内，通过黏弹性测量发现，与 3N 雌鱼和年龄较大的鱼（11 月至 3 月；20 至 24 月龄）相比，2N 雌鱼和较年轻的鱼（7 月，16 月龄）的肌肉具有更大的弹性（较低的 tan δ）。7 月时观察到最高的弹性响应和最坚实的鱼片。7 月采集的生鱼片比 9 月至 1 月（平均 288.77 g/g）的生鱼片更硬（Allo-Kramer 剪切；P < 0.05），9 月至 1 月采集的生鱼片比 3 月（366.79 g/g）采集的生鱼片更软。除 1 月样本外，经烹煮后鱼片会变得更硬。与 12 月相比，1 月的样本具有更高的烹煮产率和更软的鱼片。3N 雌鱼的脂质积累可能会润滑肌肉纤维，并在高营养水平的动物产卵期保护它们的功能不丧失。
评估了鱼类成熟度（以卵子发育为衡量标准）与可育和不育鱼的鱼片化学特性之间的关系。热变性和黏弹性特性揭示了肌肉蛋白稳定性和胶凝特性的变化，这些变化与鱼片质地的变化有关。
