Xie Menghui, Wang Meng, Liu Siyuan, Liu Yingying, Wang Ziquan, Zhou Guoping, Sui Zhiwei
Center for Advanced Measurement Science, National Institute of Metrology, Beijing 100029, China.
School of Life Science and Technology, Wuhan Polytechnic University, Wuhan 430023, China.
Foods. 2024 Sep 12;13(18):2890. doi: 10.3390/foods13182890.
The somatic cell count (SCC) refers to the number of somatic cells present in each milliliter of raw milk and serves as a crucial indicator of dairy cow udder health and raw milk quality. Traditional SCC detection methods are often time-consuming, expensive, and susceptible to bacterial interference, rendering them unsuitable for the rapid and unbiased assessment of raw milk quality. Consequently, there is an urgent need for a low-cost, accurate, and user-friendly SCC quantification method. Here, a method based on an OPD-Cu system for SCC quantification was developed. It was found that OPD oxidation signals exhibited a linear correlation with SCC. Following optimization, the detection system was established with a Cu concentration of 25 μM, an OPD concentration of 2 mM, and an incubation time of 15 min. Furthermore, the method demonstrated significant resistance to bacterial interference, though it produced weaker signals in response to bacteria. The somatic cell recovery rate in milk after pretreatment was 88.9%, and SCC was quantified accurately within 45 min, with a linear range of 10-10 cells/mL. In summary, the method developed is cost-effective, straightforward, and facilitates precise somatic cell quantification, offering significant practical value and a new approach for SCC detection in raw milk.
体细胞计数（SCC）是指每毫升原料乳中存在的体细胞数量，是奶牛乳房健康和原料乳质量的关键指标。传统的SCC检测方法通常耗时、昂贵且易受细菌干扰，不适用于对原料乳质量进行快速、无偏差的评估。因此，迫切需要一种低成本、准确且用户友好的SCC定量方法。在此，开发了一种基于OPD-Cu系统的SCC定量方法。发现OPD氧化信号与SCC呈线性相关。经过优化，建立了检测系统，铜浓度为25 μM，OPD浓度为2 mM，孵育时间为15分钟。此外，该方法对细菌干扰具有显著抗性，尽管它对细菌产生的信号较弱。预处理后牛奶中的体细胞回收率为88.9%，45分钟内可准确量化SCC，线性范围为10 - 10⁶ 个细胞/毫升。总之，所开发的方法具有成本效益、操作简单，便于精确的体细胞定量，为原料乳中SCC检测提供了重要的实用价值和新方法。
