Abstract:
Repeated freezing-thawing cycles often occur during the storage, transportation, and sales of emulsified meat products. Ice crystals produced by repeated freezing-thawing cycles can destroy the structures of muscle fibers and meat proteins, resulting in water loss and quality deterioration of meat products. It is reported that dietary fiber with strong water absorption is conducive to water retention of frozen-thawed meat products. Therefore, the effect of pea fiber on the freezing-thawing stability of 3D printed meat mince cubes filled with Pickering emulsion was investigated by means of rheometer, color difference meter, texture meter and TBARS, taking 3D printed meat mince cubes only filled with high internal phase Pickering emulsion (P) and meat mince cubes without Pickering emulsion (N) as the control. The results showed that the apparent viscosity and viscoelasticity (G' and G") of minced meat filled with Pickering emulsion were proportional to the amount of pea fiber added. When the addition of pea fiber was increased to 2% (PPF2) or more, the G' and G" of minced meat were higher than those of P and N minced meat, indicating that the addition of pea fiber could significantly improve the viscosity and mechanical strength of emulsion mince, and was further conducive to the shape preservation of printed products. However, when the added amount of pea fiber was more than 2%, the printed meat mince cubes collapsed. It indicating that excessive addition of pea fiber might interfere with the formation of muscle gel network through steric hindrance, resulting in reduced network connectivity, which was not conducive to the printing accuracy of minced meat. When freezing-thawing cycles were carried out, the shape holding capacity of printed meat mince cubes decreased. Compared with P and N meat mince cubes, PPF2 meat mince cubes had the best shape holding capacity under the same freezing-thawing treatment. The thawing loss rate of PPF2 meat mince cubes was 21.7% and 23.04% lower than that of N and P meat mince cubes, and its shrinkage rate was 24.88% and 26.26% lower than that of N and P meat mince cubes, respectively, which is due to the strong water-binding capacity and water-absorbing expansion of pea fiber. The L* values, a* values and b* values of P and PPF2 meat mince cubes were not significantly different (P>0.05), indicating that the addition of pea fiber did not change the color stability of meat mince cubes filled with Pickering emulsion. In addition, the ice crystal void and TBARS values of P and PPF2 meat mince cubes were close to each other, and were significantly better than those of N meat mince cubes (P<0.05), indicating that the addition of Pickering emulsion and pea fiber had a positive effect on limiting the growth of ice crystals. It also suggested that the addition of pea fiber did not affect the protective effect of the interfacial protein film on the internal oil in Pickering emulsion. In general, pea fiber can effectively improve the freezing-thawing stability of 3D printed pre-emulsified meat, which provides a theoretical basis for the development and quality improvement of 3D printed frozen meat products.