Quality changes of pork during frozen storage: comparison of immersion solution freezing and air blast freezing

This study evaluated the effects of freezing method and storage time on the quality changes of pork longissimus thoracis (LT). The results showed that, compared to air blast freezing (AF), better microstructure was observed in pork under immersion solution freezing (ISF) mainly due to higher freezing rate. ISF group had significantly lower thawing loss at 1, 31 and 91 days and higher shear force at 1 day than AF (P < 0.05). A significant reduction in TBARS value at 61 and 91 days was observed in ISF samples (P < 0.05). No significant differences were observed between the two treatments in the colour, cooking loss and sulfhydryl groups (P > 0.05). All quality indicators were significantly affected by storage time (P < 0.05). It is concluded that ISF could maintain better microstructure, improve water-holding capacity and inhibit lipid oxidation during pork LT frozen storage.