Mascheroni R H, Calvelo A
Centro de Investigación y Desarrollo en Criotecnologia de Alimentos (CIDCA) UNLP-CONICET-CIC. Facultad de Ciencias Exactas UNLP-47 y 115 (1900), La Plata, Argentina.
Meat Sci. 1980 Aug;4(4):267-85. doi: 10.1016/0309-1740(80)90027-3.
One of the most suitable parameters for relating the freezing rate to the volume of drip produced during the thawing of meat is the characteristic time, defined as the time necessary to reduce the temperature of the sample from -1·1°C (initial freezing point in beef) to -7°C (80% of the water frozen). However, as the freezing of beef in factories takes place with important temperature gradients, distributions of these characteristic times must be expected along the pieces of frozen meat. In order to relate these characteristic time distributions to heat transfer parameters under industrial freezing conditions, a mathematical model which simulates the freezing of beef is developed in this paper. The model establishes the heat transfer equations with simultaneous change of phase, taking into account the dependence of the thermal properties with the ice content and considering the anisotropy of the thermal conductivity according to the direction of the fibres. Boundary conditions include the possibility of thermal resistances in the refrigerated interphase. The model developed was compared with laboratory experiments performed under factory freezing conditions and showed a satisfactory agreement between theory and experiment.
将冷冻速率与肉解冻过程中产生的滴液量相关联的最合适参数之一是特征时间，其定义为将样品温度从-1.1°C（牛肉的初始冰点）降至-7°C（80%的水冻结）所需的时间。然而，由于工厂中牛肉的冷冻是在重要的温度梯度下进行的，因此沿冷冻肉块预计会有这些特征时间的分布。为了将这些特征时间分布与工业冷冻条件下的传热参数相关联，本文开发了一个模拟牛肉冷冻的数学模型。该模型建立了伴有相变的传热方程，考虑了热性能与冰含量的依赖性，并根据纤维方向考虑了热导率的各向异性。边界条件包括冷藏相间存在热阻的可能性。将开发的模型与在工厂冷冻条件下进行的实验室实验进行了比较，结果表明理论与实验之间具有令人满意的一致性。
