Investigation of fatty acid thermal transitions and stability in poultry pates enriched with vegetable components

The aim of the study was to describe the thermal characteristics of poultry pates enriched with vegetable components in relation to their chemical composition and technological process. Two poultry pates from chicken liver, chicken or turkey meat with vegetables were developed. The thermal characteristics of the raw materials and the ready pates were examined by differential scanning calorimetry; fatty acid profiles were detected by gas chromatography analysis. The study investigated the effect of such factors as heating/cooling rate and matrix effect of other components (e.g., proteins) in the raw materials and in the pates. It was observed that the cooling rate has a considerable effect on melting/crystallization temperature, enthalpy, and height of peaks in the process of pates fat crystallization, as well as peak height and enthalpy in the melting process. The first peaks formed during the crystallization were characterized by high instability, demonstrated by various peak shapes. The rapid cooling led to lowering of the melting point, assigned to the presence of unstable α crystals. The slow cooling led to mainly stable β′ crystals. The fraction of unsaturated fatty acids present in the fat was important for both crystallization rate and melting points in the raw materials and in the products as well. This effect was stronger in the pate products because of the presence of diverse components such as proteins. The results obtained could be used for the evaluation of thermal stability of pate fatty acids and further optimization of the pate thermal treatment.