School of Tourism and Cuisine, Yangzhou University, Yangzhou 225127, China; Key Laboratory of Chinese Cuisine Intangible Cultural Heritage Technology Inheritance, Ministry of Culture and Tourism, Yangzhou, China.
School of Tourism and Cuisine, Yangzhou University, Yangzhou 225127, China.
Food Res Int. 2024 Dec;197(Pt 1):115148. doi: 10.1016/j.foodres.2024.115148. Epub 2024 Sep 27.
This study aimed to investigate the effect of L-lysine (Lys) on the color of pork and reveal the possible mechanism. The results showed that the L* and a* values increased from 53.69 to 56.32, 56.39, and 56.47, and from 12.93 to 13.21, 13.24, and 13.52 with the addition of 0.1 %, 0.15 % and 0.2 % Lys, respectively. Meanwhile, the oxymyoglobin (Fe) levels increased from 21.14 % to 22.63 %, 23.83 %, and 23.53 %, while the metmyoglobin (Fe) levels decreased from 44.69 % to 40.28 %, 41.21 %, and 41.63 % with the addition of 0.1 %, 0.15 % and 0.2 % Lys, respectively. Additionally, the addition of Lys increased total sulfhydryl and active sulfhydryl contents, and decreased the levels of reactive oxygen species (ROS) (P<0.05). The particle size and the absolute value of the ζ-potential increased with the addition of Lys, reaching maximum values of 534.39 nm and -13.73 mV, respectively. The molecular dynamics results suggested that Lys can bind to myoglobin (Mb) through hydrophobic interactions and hydrogen bonds, forming a stable Lys-Mb complex, acting as a protective shield to prevent the entry of ROS and other oxidizing agents. Finally, the addition of 0.15 % Lys resulted in the highest surface hydrophobicity, which was 5.79 μg. The multispectral results indicated that Lys primarily induces changes in the secondary and tertiary structures of Mb through interactions with tyrosine residues. These changes stabilized the free-moving rings within the amino acid residues of Mb, thereby improving the structural stability of Mb and ultimately enhancing the color stability of pork. In summary, Lys improved meat color stability through a dual mechanism of antioxidation and interaction with Mb to alter its conformational stability.
本研究旨在探讨 L-赖氨酸(Lys)对猪肉颜色的影响,并揭示其可能的机制。结果表明,随着 0.1%、0.15%和 0.2%Lys 的添加,L值和 a值分别从 53.69 增加到 56.32、56.39 和 56.47,从 12.93 增加到 13.21、13.24 和 13.52。同时,氧合肌红蛋白(Fe)水平从 21.14%增加到 22.63%、23.83%和 23.53%,而高铁肌红蛋白(Fe)水平从 44.69%下降到 40.28%、41.21%和 41.63%。此外,随着 Lys 的添加,总巯基和活性巯基含量增加,活性氧(ROS)水平降低(P<0.05)。Lys 的添加增加了颗粒大小和ζ-电位的绝对值,达到 534.39nm 和-13.73mV 的最大值。分子动力学结果表明,Lys 可以通过疏水相互作用和氢键与肌红蛋白(Mb)结合,形成稳定的 Lys-Mb 复合物,作为防止 ROS 和其他氧化剂进入的保护屏障。最后,添加 0.15%Lys 可使表面疏水性达到最高,为 5.79μg。多光谱结果表明,Lys 主要通过与酪氨酸残基相互作用,诱导 Mb 的二级和三级结构发生变化。这些变化稳定了 Mb 氨基酸残基中自由运动的环,从而提高了 Mb 的结构稳定性,最终增强了猪肉的颜色稳定性。总之,Lys 通过抗氧化和与 Mb 相互作用的双重机制改善了肉色稳定性,从而改变了 Mb 的构象稳定性。