The influence of long-term storage, temperature and type of packaging materials on the lipid oxidation and flesh color of frozen Atlantic herring fillets (Clupea harengus)

•The oxidation of herring fillets was studied at −25/−45 °C during 1 year of storage.•The packaging material with oxygen barrier inhibited the oxidation significantly.•The liquid fraction of fats was measured.•The oxygen penetration inside the package was discussed.

The oxidation and color characteristics of Atlantic herring fillets were examined during the long-term frozen storage at −25 and −45 °C. The effects of packing materials with low and medium oxygen barriers were studied as well. At the temperature of −45 °C, the peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) formation were significantly inhibited. The same desirable effect was detected for packaging material with a medium oxygen barrier at −25 °C. A regression model of the herring fillets' oxidation was verified. The storage time, temperature and packaging materials affected the color alteration. The differential scanning calorimetry (DSC) analyses of herring oil revealed a melting between −60.67 °C and 21.40 °C. The liquid fraction in the fish oil was determined. It was high for all the storage temperatures, thus the oxygen concentration in the package was considered to be the dominating factor for the herring's oxidation during frozen storing.