Wee Sheena, Chua Sew Lay, Yu Dingyi, Koh Shoo Peng, Lee Kah Meng, Wu Yuansheng, Chan Sheot Harn
National Centre for Food Science, Singapore Food Agency, Singapore 609919.
Department of Food Science & Technology, National University of Singapore, Singapore 117543.
JDS Commun. 2023 Oct 3;5(1):7-12. doi: 10.3168/jdsc.2023-0392. eCollection 2024 Jan.
Nisin, a bacteriocin produced through fermentation using bacterium , has several commercial variants such as nisin A and nisin Z. Nisin serves as a natural preservative with antimicrobial properties in various food products, including dairy and beverages, for extending product shelf life. The efficacy and safety of nisin A as a bacteriocin has been well characterized. However, there is limited evidence regarding the efficacy, stability, and safety of nisin Z as a food preservative, as it has not undergone comprehensive regulatory reviews. In this work, we studied the stability of nisin A and Z in a selection of yogurt drinks and found nisin to be unstable, particularly in fruit-flavored yogurt drinks. Both nisin A and Z could experience significant degradation leading to the nisin parent ion peaks dropping below detectable level before the product's expiry date. Compared with nisin A, the formation of oxidized metabolite nisin Z+O appeared to be the predominant reaction for nisin Z. These findings highlight the need for further scientific research to understand the behavior of nisin Z under different application conditions, which is crucial for assessing the efficacy and safety of nisin Z under these conditions. One potential application of this knowledge is to optimize the formulation of yogurt-based drinks to stabilize nisin Z and sustain its biopreservative function throughout the product's shelf life. Additionally, the current study shows that for the testing of the presence of nisin A or nisin Z, it is imperative to cover both the parent and the main degradant(s) of nisin. This is especially true for nisin Z, for which the regulatory approval status may vary in different markets. As such, the confirmative identification of nisin Z and its key metabolites in commercial products would be essential.
乳酸链球菌素是一种通过细菌发酵产生的细菌素，有几种商业变体，如乳酸链球菌素A和乳酸链球菌素Z。乳酸链球菌素在包括乳制品和饮料在内的各种食品中作为具有抗菌特性的天然防腐剂，用于延长产品保质期。乳酸链球菌素A作为一种细菌素的功效和安全性已得到充分表征。然而，关于乳酸链球菌素Z作为食品防腐剂的功效、稳定性和安全性的证据有限，因为它尚未经过全面的监管审查。在这项工作中，我们研究了乳酸链球菌素A和Z在一系列酸奶饮料中的稳定性，发现乳酸链球菌素不稳定，尤其是在水果味酸奶饮料中。乳酸链球菌素A和Z都可能发生显著降解，导致在产品保质期之前乳酸链球菌素母离子峰降至可检测水平以下。与乳酸链球菌素A相比，氧化代谢产物乳酸链球菌素Z+O的形成似乎是乳酸链球菌素Z的主要反应。这些发现凸显了进一步开展科学研究以了解乳酸链球菌素Z在不同应用条件下行为的必要性，这对于评估乳酸链球菌素Z在这些条件下的功效和安全性至关重要。这一知识的一个潜在应用是优化基于酸奶的饮料配方，以稳定乳酸链球菌素Z并在产品整个保质期内维持其生物防腐功能。此外，当前研究表明，对于检测乳酸链球菌素A或乳酸链球菌素Z的存在，必须同时检测乳酸链球菌素的母体和主要降解产物。对于乳酸链球菌素Z尤其如此，其监管批准状态在不同市场可能有所不同。因此，在商业产品中对乳酸链球菌素Z及其关键代谢产物进行确证鉴定至关重要。
