Physicochemical parameters and freshness indicators of alimentary poultry fat during refrigeration (2 ... 4oC) and freezing (-15 ...- 18oC) storage were studied. In assessing the various stages of oxidative changes, peroxide value (PV), iodine value (IV), thiobarbituric acid reactive substances (TBARS) and the presence of epyhidrinic aldehyde (Kreis reaction) were determined to identify and measure the primary and secondary oxidation compounds, fatty acid profile and acidity index determination for measuring the degree of lipolysis. Appreciation of oxidation process installation was performed also by microscopic examination. PV registered an increased durin storage at -15...-18oC, a very significant increase was observed at 90 days when riched the value of 7.9±0.14 meq O2/kg due to the formation of a large amount of peroxides, at 120 days the value increased relatively slow and after 150 days it was registered a decrease of PV to 7.7±0.09 meq O2/kg, which corresponds to the interruption stage and the split in secondary compounds. Based on the obtained results it can be concluded that poultry fat stored under freezing was fresh up to 2 months, up to 4 months the freshness was relatively due to the slightly acidic taste and smell and the high value of PV, and in the 5th month the oxidative spoilage was installed also highlighted by the color, taste and smell deffects. Storage temperature had a very significant effect (P≤0.001) and storage time a significant effect (P≤0.05) on the installation of advanced processes of hydrolysis and oxidation, the acceptability tolerance of fat stored under freezing was almost twice for that of fat stored under refrigeration.
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