The aim of the master’s thesis was to examine the effect of added salt and brine on the thermal properties of pork meat and to evaluate the potential use of freezing temperature curves as a simple method for detecting adulteration with added salt. The addition of salt influences water activity, freezing temperature, and the proportion of freezable water, which is reflected in changes in cooling behaviour and phase transitions. The study included pork loin in whole-muscle form and homogenized meat, to which brines of different concentrations or NaCl were added. In addition to laboratory-prepared samples, commercially available meat products were also analysed. During freezing, temperature curves were monitored and key parameters were determined, including the minimum temperature before the onset of crystallization (T1), the plateau temperature (T2), the duration of freezing, and the cooling rate. The results were compared with differential scanning calorimetry (DSC), which provided the onset temperature of the phase transition, the peak temperature of the thermogram, and the melting enthalpy. The addition of salt and brine lowered the phase transition temperatures in all measurement series, consistent with reduced water activity. The effect was more pronounced in homogenized meat, where the disrupted muscle structure allowed more homogeneous salt distribution. Meat ageing further influenced crystallization behaviour. The results showed good agreement between freezing temperature curves and DSC analysis, confirming that temperature curves reliably reflect thermodynamic changes in meat samples. The method proved to be a promising screening technique for detecting brine addition in meat, particularly when used in combination with other analytical approaches.
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