New technique for determining the critical freezing temperatures of chicken breast based on radiofrequency photospectrometry

Abstract

[EN] Food freezing operations require an extreme knowledge of the thermal properties of the food to be frozen, in order to achieve a product that at the thawing time preserves the best sensory and food quality properties, and also preserves food safety. Within these properties it is necessary to know the initial freezing temperature (Tm0), the freezing temperature of the maximally freeze concentrated liquid phase (Tm'), the glass-transition temperature of the maximally freeze concentrated liquid phase (Tg') and others. However, the techniques to determine these properties are long, tedious, and sometimes with high variability, one of the most important technique is Differential Scanning Calorimetry (DSC). In this work, the use of photospectrometry in the radiofrequency range (PFR) is proposed, as a fast and reliable method for determining the thermal properties of chicken breast in the freezing process, comparing it with the DSC technique. The results showed a Tg' of -17.50 +/- 1.05, obtained by the PFR technique, using the beta dispersion, similar as the result obtained by DSC technique (-16.73 degrees C +/- 0.13). Therefore, the PFR is a fast, reliable, and easy technique to determine the critical temperatures of the food freezing process.