Key Laboratory of Meat Processing and Quality Control, MOE, Key Laboratory of Meat Processing, MOA, Jiangsu Synergetic Innovation Center of Meat Processing and Quality Control, Nanjing Agricultural University, Nanjing 210095, PR China; State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo 315211, PR China.
Key Laboratory of Meat Processing and Quality Control, MOE, Key Laboratory of Meat Processing, MOA, Jiangsu Synergetic Innovation Center of Meat Processing and Quality Control, Nanjing Agricultural University, Nanjing 210095, PR China.
Food Chem. 2020 Jun 15;315:126318. doi: 10.1016/j.foodchem.2020.126318. Epub 2020 Jan 30.
To better understand the contribution of myosin light chain (MLC) isoforms to sensory defects in Jinhua ham, dipeptidyl peptidase (DPP) activities, peptide fragments, cleavage sites and the potential of DPP to develop sensory defects of dry-cured ham were evaluated and discussed in normal and defective hams. Higher residual activities of DPP I were found in defective ham compared with normal ham; approximate 3-fold peptide fragments were identified in defective ham than in normal ham. These regions of positions 11-35 and 116-141 in MLC 1, 13-53 and 139-156 in MLC 2, and 18-50 in MLC 3 contributed to the intense generation of peptide fragments in defective ham. PLS-DA further revealed DPP I showing intense response to degrade peptides. Cleavage sites including Glu-128, Tyr-132 and Glu-133 were responsible for the intense release of dipeptides in defective ham. These cleavages could play key role in discriminating taste attributes between defective and normal hams.
为了更好地理解肌球蛋白轻链（MLC）同工型对金华火腿感官缺陷的贡献，研究了正常和缺陷火腿中二肽基肽酶（DPP）的活性、肽片段、切割位点以及 DPP 发展干腌火腿感官缺陷的潜力。与正常火腿相比，缺陷火腿中 DPP I 的残留活性更高；与正常火腿相比，缺陷火腿中鉴定出约 3 倍的肽片段。MLC1 的位置 11-35 和 116-141 区域、MLC2 的位置 13-53 和 139-156 区域以及 MLC3 的位置 18-50 区域有助于缺陷火腿中肽片段的大量产生。PLS-DA 进一步表明，DPP I 强烈响应降解肽。包括Glu-128、Tyr-132 和 Glu-133 的切割位点负责缺陷火腿中二肽的强烈释放。这些切割可能在区分缺陷和正常火腿的味道属性方面发挥关键作用。
