The impact of quick-freezing methods on the quality, moisture distribution and microstructure of prepared ground pork during storage duration

• Published in: Ultrasonics sonochemistry Vol. 78; p. 105707
• Main Authors: Wu, Zeyu, Ma, Wanru, Xian, Zhaojun, Liu, Qingsong, Hui, Ailing, Zhang, Wencheng
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-10-2021; Elsevier
• Subjects: Animals; Cooking; Freezable water; Freezing; Freezing rate; Ice crystals; Myofibrillar protein; Original; Pork Meat; Quality deterioration; Swine; Ultrasound-assisted immersion freezing; Water; Freezing rate; Myofibrillar protein; Ice crystals; Ultrasound-assisted immersion freezing; Freezable water; Quality deterioration
• ISSN: 1350-4177; 1873-2828
• DOI: 10.1016/j.ultsonch.2021.105707

•Ultrasound-assisted immersion freezing (UIF) was used for preparedgroundpork(PGP).•UIF inhibited protein denaturation, protein oxidation and fat oxidation of PGP.•UIF promoted the water distribution of PGP by inhibited the ice crystals growth.•UIF reduced the damage of ice crystals to the protein network structure of PGP.•UIF is an effective way to reduce PGP deterioration during frozen storage.
The aim of present study was to investigate the influences of ultrasound-assisted immersion freezing (UIF), immersion freezing (IF) and air freezing (AF) on the quality, moisture distribution and microstructure properties of the prepared ground pork (PGP) during storage duration (0, 15, 30, 45, 60, 75 and 90 days). UIF treatment significantly reduced the freezing time by 60.32% and 39.02%, respectively, compared to IF and AF (P < 0.05). The experimental results of quality evaluation revealed that the L* and b* values, juice loss, cooking loss, TBARS values and carbonyl contents were decreased in the UIF treated samples, while the a* value, peak temperatures (Tm), enthalpy (ΔH) and sulfhydryl contents were significantly higher than those of IF and AF treated samples (P < 0.05). In addition, low-field nuclear magnetic resonance (LF-NMR) and differential scanning calorimetry (DSC) analysis demonstrated that UIF inhibited the mobility of immobilized water and reduced the loss of immobilized and free water, and then a high water holding capacity (WHC) was achieved. Compared to the IF and AF treatments, the UIF treated PGP samples possessed better microstructure. Therefore, UIF could induce the formation of ice crystals with smaller size and more even distribution during freezing process, which contributed to less damage to the muscle tissue and more satisfied product quality.