GenPhySE, Université de Toulouse, INRA, ENVT, Toulouse INP, 31326 Castanet Tolosan, France.
ASSELDOR, Station d'expérimentation appliquée et de démonstration sur l'oie et le canard, La Tour de Glane, 24420 Coulaures, France.
Poult Sci. 2019 Nov 1;98(11):5724-5733. doi: 10.3382/ps/pez359.
In foie gras production the technological yield after the cooking process is one of the main issues of processors as it is closely linked to the cooking melting rate. This rate is subjected to strict laws and regulations since it directly affects the organoleptic and technological qualities of this gourmet product. The objective of the study was to better understand the liver fattening and the technological yield decrease during the overfeeding kinetics. A flock of 210 mule ducks was reared and then overfed during 12 D with 2 overfeeding programs; in the test group the amounts of corn in the first meals were higher than in the control group (+430 g during the whole period). Ducks were slaughtered at the end of the rearing period (D0, n = 15) and every other day (D2 to D12, n = 15 by group). Duck performances, anatomical dissections and physical and biochemical liver characteristics were registered. The performances were equivalent in the groups (P > 0.1). The evolution of the liver weight was then analyzed in detail in relation with the evolution of its biochemical composition. A two-step evolution occurred in the liver metabolism, first a main glycogen storage and then a strong lipid storage. A model to predict the liver weight was established with only BWs and feed intakes (R² = 0.83). The technological yield was determined on foie gras weighing more than 300 g (D6 to D12). The melting process was high during the last 2 D. The technological yield reached 72% at D12, for 758 g foie gras, and a strong negative correlation was observed with liver weight (-0.83; P < 0.001). A model to predict the technological yield was established with the liver weight and the liver color parameters (R² = 0.71). This study highlights the compromise between foie gras weight and its quality.
鹅肝生产过程中，烹饪后的技术产率是加工者关注的主要问题之一，因为它与烹饪熔化率密切相关。该速率受到严格的法律法规的限制，因为它直接影响到这种美食产品的感官和技术质量。本研究的目的是更好地了解肝脏育肥和过度喂养期间技术产率下降的原因。饲养了 210 只骡鸭，然后在 12 天内进行过度喂养，分为两组；实验组的第一餐玉米量比对照组高（整个时期高 430 克）。在育肥期结束时（D0，n = 15）和每隔一天（D2 至 D12，每组 n = 15）进行屠宰。记录鸭的表现、解剖和物理化学肝脏特性。两组的表现相当（P > 0.1）。然后详细分析肝脏重量的变化与生化组成的变化之间的关系。肝脏代谢经历了两个阶段的演变，首先是主要的糖原储存，然后是强烈的脂质储存。建立了一个仅用 BW 和饲料摄入量预测肝脏重量的模型（R² = 0.83）。在 D6 至 D12 期间，对重量超过 300 克的鹅肝进行了技术产率测定。最后 2 天的熔化过程很高。在 D12 时，技术产率达到 72%，产 758 克鹅肝，与肝脏重量呈强负相关（-0.83；P < 0.001）。建立了一个用肝脏重量和肝脏颜色参数预测技术产率的模型（R² = 0.71）。本研究强调了鹅肝重量与其质量之间的平衡。
