Properties of skipjack tuna loins subjected to high-pressure processing (HPP) at 150 to 600 MPa for 1 to 5 min were compared with those of loin that underwent steam cooking for 10 min. Protein denaturation in HPP-treated loins increased with increasing pressure level, but these loins retained between 1.1% and 2.4% more water than steam-cooked loin. Water holding capacity decreased from 57% to 44% when the loins were treated at 600 MPa. ΔE value of HPP loins was between 5.8 and 26.3 when treated at 150 to 600 MPa, whereas it was 34.1 for steam-cooked sample. Hardness of HPP loins increased from 648 to 1,019, 1,918, 5,249, and 4,092 g and springiness changed from 85.2% to 79.7%, 78.2%, 91.7%, and 90.7%, respectively, when treated at 150, 300, 450, and 600 MPa. Protein fibers of HPP loins had a more irregular shape than those of steam-treated loin. Histamine levels of HPP-treated loins were in the range of 3.08 to 3.35 μg/g, identical to that of steam-treated loin. Thiobarbituric acid assay demonstrated that the level of lipid oxidation increment in HPP-treated loins was twice as high as that in steam-cooked one. Undesirable volatile compound contents in tuna loins decreased with increasing degree of protein denaturation. Steam cooking and HPP at 150, 300, 450, and 600 MPa decreased the total aerobic counts by 4.75, 0.12, 1.20, 4.69, and 6.08 log CFU/g, respectively. These results suggest that HPP at 450 MPa and above has the potential to be used as an alternative to the tuna precooking process. PRACTICAL APPLICATION Information presented here can serve as a guideline for the selection of appropriate conditions for HPP of tuna loins. Our results show that HPP has a potential to replace the highly energy-intensive steam precooking step, which is traditionally required in a canned tuna production process.

中文翻译：

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高压处理后鲣鱼 (Katsuwonus pelamis) 的物理化学、微观结构和微生物特性

将在 150 至 600 MPa 高压处理 (HPP) 1 至 5 分钟的鲣鱼腰部与蒸煮 10 分钟的腰部进行比较。HPP 处理的腰部的蛋白质变性随着压力水平的增加而增加，但这些腰部比蒸汽烹制的腰部保留的水分多 1.1% 至 2.4%。当腰部在 600 MPa 下处理时，持水能力从 57% 下降到 44%。在 150 至 600 MPa 处理时，HPP 腰部的 ΔE 值在 5.8 至 26.3 之间，而蒸汽烹制样品的ΔE 值为 34.1。在 150、300、450 和 600 处理时，HPP 腰部的硬度从 648 增加到 1,019、1,918、5,249 和 4,092 g，弹性分别从 85.2% 变为 79.7%、78.2%、91.7% 和 90.7%兆帕。HPP 腰部的蛋白质纤维比蒸汽处理的腰部具有更不规则的形状。HPP 处理的腰部的组胺水平在 3.08 至 3.35 μg/g 的范围内，与蒸汽处理的腰部相同。硫代巴比妥酸测定表明，HPP 处理的腰部中脂质氧化增加的水平是蒸煮腰部的两倍。金枪鱼腰部中有害的挥发性化合物含量随着蛋白质变性程度的增加而减少。150、300、450 和 600 MPa 的蒸汽烹饪和 HPP 分别使总需氧菌计数降低 4.75、0.12、1.20、4.69 和 6.08 log CFU/g。这些结果表明，450 MPa 及以上的 HPP 有可能用作金枪鱼预煮过程的替代品。实际应用 这里提供的信息可以作为选择金枪鱼腰部 HPP 合适条件的指南。