Changes in physicochemical properties and fatty acid composition of pork following long-term frozen storage

The objective of this study was to investigate the effect of long-term frozen storage (2 years) of pork on colour stability, lipid and protein oxidation, drip/thawing losses and intramuscular fatty acid composition, as well as to examine the relationships among them. Pork quality parameters were significantly altered by frozen storage during 2 years, causing an increase in pH values, drip and thawing losses and metmyoglobin percentage, and a decrease in colour indices (a* and b* values) and oxymyoglobin percentage. The percentage of intramuscular fat and total saturated and monounsaturated fatty acids were significantly higher in pork after 2 years of storage at −20 °C, whereas it had the lowest values of polyunsaturated fatty acids, especially n-3 long chain fatty acids. Furthermore, the relationships among colour stability, lipid and protein oxidation, thawing losses and fatty acid profile revealed the complex interrelations generated during frozen storage.