This work aims to develop an efficient sensing device to detect milk freshness when stored at typical home conditions. The synthesis of the pH-sensitive optode array, the experimental setup for milk freshness monitoring, and the optode array images acquisition procedure are presented. The employment of various chemometric tools on optode array RGB triplets to visualize, compare, and predict the spoilage of commercial types of milk is discussed. The conclusions drawn from multivariate analyses on optode colors were confirmed using different independent methods. Despite the apparent simplicity, the here proposed sensing device fulfills the requirements for both consumer-friendly naked-eye analysis and chemometrics-assisted prediction of milk freshness. Furthermore, the application of the sensing device on real milk samples during spoilage at home conditions represents a major step forward in the panorama of freshness indicators for dairy products.

中文翻译：

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基于 EVOH 的 pH 敏感光极阵列和化学计量学：从裸眼分析到预测建模以检测牛奶新鲜度

这项工作旨在开发一种有效的传感设备，以检测在典型家庭条件下储存的牛奶新鲜度。介绍了 pH 敏感光极阵列的合成、牛奶新鲜度监测的实验装置和光极阵列图像采集程序。讨论了在光极阵列 RGB 三元组上使用各种化学计量工具来可视化、比较和预测商业类型牛奶的变质。使用不同的独立方法证实了从对光极颜色的多变量分析得出的结论。尽管表面上很简单，但这里提出的传感装置满足了对消费者友好的裸眼分析和化学计量学辅助的牛奶新鲜度预测的要求。此外，