Calculation of full process freezing time in minced fish muscle

Abstract

The present manuscript is the expansion of the method Modelling of freezing time described in a previous paper. This modeling was used for simulating freezing times required for the inactivation of anisakids. The method described here can also be used for a number of other applications where the time or the temperature of the food needs to be modeled. In general, when a food is brought from room temperature to temperatures below −5∘C, the temperature kinetics follow three different parts which include cooling from initial temperature to the initial freezing point, freezing from the freezing point to −5∘C in the center of the food, and cooling from −5∘C to the final temperature in the center of the food. The present customized procedure is mainly based upon established estimation procedures. Following the description of the methods, an example of the calculation for freezing hake (Merluccius merluccius) mince muscle is provided for each of the phases. The method consists in the following: • Calculation of the pre freezing and sub freezing times with a similar procedure but separately since the sample has different thermo physical properties in each stage (cooling). • Calculation of the freezing time first for an infinite flat plate, and then a correction is applied for the actual geometry (finite cylinder). • The total freezing time is the sum of the three separate parts of the freezing process.

Keywords

• Calculation of full process freezing time in minced fish muscle