Key Laboratory of Meat Processing and Quality Control, Ministry of Education, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
Key Laboratory of Meat Processing and Quality Control, Ministry of Education, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
Food Res Int. 2022 Jun;156:111365. doi: 10.1016/j.foodres.2022.111365. Epub 2022 May 14.
Leuconostoc mesenteroides are generally recognized as a group of specific spoilage organisms in meat and poultry products, which cause acidification and blown pack spoilage of meat. In this study, a total of 6 representative strains selected from 55 L. mesenteroides isolated from spoiled meat were tested to evaluate the spoilage ability by metabonomics and in-situ analysis. The intra-species spoilage heterogeneity was observed. The results showed that the acidifying and gas production capacity of L. mesenteroides was distinct between in broth and on meat. The pH of inoculated MRS broth was 1.38 to 1.49 units lower than that of the sterile broth and the height of gas column in Durham tube ranged from 8 mm to 11 mm at 72 h, all significantly different from the sterile group. Metabonomic analysis revealed that the main produced organic acids were myristic acid, butyric acid, lactic acid, valeric acid and enoic acid. It also illustrated that the UHPLC-MS/MS profiles of L4 and L5 was distinct from the other strains. In terms of meat inoculated with L. mesenteroides, most pH values did not show significant difference from that of the meat without inoculation, and vacuum packaging distension was not observed. Increase of TVB-N was very limited as well. The growth rate of L2, L4 and L5, as well as the pH changes of L3 and L6, varied wildly between different growth matrix. The differences between L5 and the other strains were the most obvious. The growth rate of L5 was the highest in vitro but the lowest in situ, and its acid- and gas-producing rate was relatively lower than that of the other groups. The results exhibited that it is limited to judge the bacteria-derived meat spoilage only by in-vitro growth. What should be focused on is the spoilage strengths in situ rather than the pure standard culture. In conclusion, the present study analyses profiles related to growth, acidification and gas production of L. mesenteroides in vitro and in situ, and provides references for emphasis on future research to reduce the loss of meat in consequence of spoilage.
肠膜明串珠菌通常被认为是肉类和家禽产品中一组特定的腐败菌，它们会导致肉类酸化和胀包腐败。在本研究中，从腐败肉中分离出的 55 株肠膜明串珠菌中选择了 6 株代表性菌株，通过代谢组学和原位分析来评估其腐败能力。观察到种内腐败的异质性。结果表明，肠膜明串珠菌在肉汤中和在肉上的酸化和产气能力明显不同。接种 MRS 肉汤的 pH 值比无菌肉汤低 1.38 至 1.49 个单位，72 小时时杜伦管中的气柱高度在 8 至 11 毫米之间，所有这些都与无菌组有显著差异。代谢组学分析表明，主要产生的有机酸是肉豆蔻酸、丁酸、乳酸、戊酸和烯酸。它还表明，L4 和 L5 的 UHPLC-MS/MS 图谱与其他菌株明显不同。就接种肠膜明串珠菌的肉而言，大多数 pH 值与未接种肉的 pH 值没有显著差异，也没有观察到真空包装膨胀。TVB-N 的增加也非常有限。L2、L4 和 L5 的生长速度以及 L3 和 L6 的 pH 值变化在不同的生长基质中变化很大。L5 与其他菌株之间的差异最为明显。L5 在体外的生长速度最高，但在体内的生长速度最低，其产酸和产气速度相对低于其他组。结果表明，仅通过体外生长来判断细菌引起的肉腐败是有限的。应该关注的是现场的腐败强度，而不是纯标准培养。总之，本研究分析了肠膜明串珠菌在体外和体内生长、酸化和产气的相关谱，并为未来减少因腐败而导致的肉类损失的研究提供了参考。
