College of Mechanical and Electronic Engineering, Shandong Agricultural University, Tai'an, China.
Faculty of Agriculture, Iwate University, Morioka, Japan.
J Food Sci. 2024 Jul;89(7):4079-4092. doi: 10.1111/1750-3841.17165. Epub 2024 Jun 7.
Ohmic heating (OH) at different conditions (voltage: 15, 20, 25 V; frequency: 1, 5, 10 kHz) and one-step water bath (WB) were used to heat wash and unwash surimi prepared from fresh pre-rigor common carp. The optimal heating conditions were established through assessments of gel strength, Texture Profile Analysis (TPA), water-holding capacity (WHC), whiteness, and sensory evaluation. Then, the impact of heating modes on gelation properties of unwashed surimi based on the optimal heating conditions was investigated. The study findings indicated a significant enhancement in gel properties compared to WB. Unwashed surimi gel properties showed improvement when derived from freshly caught raw fish and subjected to OH treatment. Moreover, variations in frequencies and voltages were observed to influence the heating rate. Optimal gel quality was achieved at 10 kHz 20 V (10 V/cm), facilitating swift progression through the gel deterioration stage, inhibition of protein hydrolyzing enzymes activity, and establishment of a stable gel network. Continuing to increase the heating rate would disrupt its network structure, resulting in diminished gel strength and WHC. The best quality of unwashed surimi gel was achieved by heating to 40°C for 30 min, followed by heating to 90°C for another 30 min (40°C 30 min + 90°C 30 min) under 10 kHz 20 V. The gel strength increased when held for 1 h at 40°C. For optimal heating efficiency, the heating mode of 40°C 30 min + 90°C 30 min is recommended to prepare unwashed surimi gel. PRACTICAL APPLICATION: Ohmic heating, as a rapid food heat treatment method, can both increase the heating rate and improve the gelation properties of freshwater surimi. There is a wide range of potential applications for the heat treatment of the surimi.
欧姆加热（OH）在不同条件（电压：15、20、25V；频率：1、5、10kHz）和一步水浴（WB）下加热新鲜僵直期鲤鱼制备的洗和未洗鱼糜。通过凝胶强度、质地分析（TPA）、持水能力（WHC）、白度和感官评价评估来确定最佳加热条件。然后，研究了在最佳加热条件下加热方式对未洗鱼糜凝胶性质的影响。研究结果表明，与 WB 相比，凝胶性质有显著提高。未洗鱼糜凝胶性质从新鲜捕获的生鱼中获得，并进行 OH 处理时会得到改善。此外，频率和电压的变化被观察到会影响加热速率。在 10kHz 20V（10V/cm）下，可获得最佳凝胶质量，这有利于快速通过凝胶劣化阶段，抑制蛋白水解酶的活性，并建立稳定的凝胶网络。继续提高加热速率会破坏其网络结构，导致凝胶强度和 WHC 降低。通过在 10kHz 20V 下加热 40°C 30min，然后再加热 90°C 30min（40°C 30min+90°C 30min）来制备未洗鱼糜凝胶，可获得最佳的未洗鱼糜凝胶质量。在 40°C 下保持 1 小时可提高凝胶强度。为了获得最佳的加热效率，建议采用 40°C 30min+90°C 30min 的加热方式来制备未洗鱼糜凝胶。实际应用：欧姆加热作为一种快速的食品热处理方法，既可以提高加热速率，又可以改善淡水鱼糜的凝胶性质。该热处理方法在鱼糜处理方面有广泛的应用前景。
