Department of Electrical Energy and Information Engineering "Guglielmo Marconi" (DEI), Alma Mater Studiorum-Università di Bologna, 40126 Bologna, Italy.
Department of Physics and Astronomy "Augusto Righi" (DIFA), Alma Mater Studiorum-Università di Bologna, 40126 Bologna, Italy.
Sensors (Basel). 2023 May 23;23(11):5002. doi: 10.3390/s23115002.
Useful information about the oxidative stability of a virgin olive oil in terms of oxidation products and antioxidant compounds can be obtained by analyzing the peroxide index (PI) and total phenolic content (TPC), respectively. These quality parameters are usually determined in a chemical laboratory using expensive equipment, toxic solvents, and well-trained personnel. This paper presents a novel portable sensor system for in the field and rapid determination of PI and TPC that is particularly suited in the case of small production environments that cannot afford an internal laboratory for quality control analysis. The system is small, can be powered by both USB ports and batteries, is easy to operate, and integrates a Bluetooth module for wireless data transmission. It estimates the PI and TPC in olive oil from the measurement of the optical attenuation of an emulsion between a reagent and the sample under test. The system has been tested on a set of 12 olive oil samples (eight for calibration and four for validation), and the results have shown how the considered parameters can be estimated with good accuracy. The maximum deviation from the results obtained with the reference analytical techniques is 4.7 meq O/kg in the case of PI and 45.3 ppm in the case of TPC for the calibration set, while it is 14.8 meq O/kg in the case of PI and 55 ppm in the case of TPC for the validation set.
可以通过分析过氧化物指数（PI）和总酚含量（TPC），分别获得有关特级初榨橄榄油氧化稳定性的有用信息，这些信息涉及氧化产物和抗氧化化合物。这些质量参数通常使用昂贵的设备、有毒溶剂和训练有素的人员在化学实验室中确定。本文提出了一种新颖的便携式传感器系统，用于现场和快速测定 PI 和 TPC，特别适用于无法承担内部实验室质量控制分析的小型生产环境。该系统体积小，既可以通过 USB 端口也可以通过电池供电，操作简单，并集成了蓝牙模块，可实现无线数据传输。它通过测量试剂和待测试样品之间的乳状液的光衰减来估计橄榄油中的 PI 和 TPC。该系统已在 12 个橄榄油样本（8 个用于校准，4 个用于验证）上进行了测试，结果表明可以很好地估计所考虑的参数。对于校准集，PI 的最大偏差为 4.7 meq O/kg，TPC 的最大偏差为 45.3 ppm；对于验证集，PI 的最大偏差为 14.8 meq O/kg，TPC 的最大偏差为 55 ppm。
