Contributions of Fat Content and Oxidation to the Changes in Physicochemical and Sensory Attributes of Pork Dumpling Filler during Frozen Storage

This study was conducted to evaluate the contributions of fat addition levels and storage duration at -18 °C to the oxidation and physicochemical changes of frozen pork dumpling filler. With an increase in the fat addition, thiobarbituric acid-reactive substances and carbonyl production increased (P < 0.05), the transition temperatures (Tmax) shifted to lower temperatures, and the total enthalpy (ΔH) of protein denaturation reduced (P < 0.05). Dynamic rheological measurements revealed a compromised viscoelastic network in filler protein gels with increased fat levels and storage time. Increasing the fat level also increased cooking loss and decreased breaking strength (P < 0.05). The sensory results showed that the dumplings with a high fat level had significantly higher texture, juiciness, and overall acceptability scores (P < 0.05). The results suggest that the dumplings with a high fat level stored for long periods enhanced oxidation and cooking loss and decreased breaking strength; however, it is important to add proper fat considering the palatability.