Effect of freeze-thaw cycles on the quality of quick-frozen pork patty with different fat content by consumer assessment and instrument-based detection

The change in quality of quick-frozen patties containing different amounts of added fat (0%, 5%, 10%, 15%, and 20%) under different freeze-thaw (F-T) cycles (a F-T cycle was performed by freezing at -18 degrees C and thawing at 4 degrees C) was evaluated. The results showed that the a*-values of samples were significantly decreased, while L* values, b*-values, thawing loss, and cooking loss were notably increased after 3 F-T cycles. Low-field nuclear magnetic resonance (LF-NMR) results showed that the water mobility of patties was enhanced. Textural properties (hardness, springiness, cohesiveness, and chewiness) of patties were significantly decreased after 5 FT cycles (P < 0.05). Lipid and protein oxidation were aggravated with increasing fat content and number of FT cycles, as confirmed by the increase in lipid peroxides, TBARS, and carbonyl content. Therefore, the results from instrument-based detection and consumer scores indicated that repeated F-T cycles accelerated the quality deterioration of quick-frozen pork patties, and rendered them unacceptable after 3 F-T cycles.

Automated summary

The study evaluated the quality changes of quick-frozen patties with different fat contents and freeze-thaw cycles, showing that repeated freeze-thaw cycles accelerated the deterioration of patty quality and rendered them unacceptable after 3 cycles.