Active Infrared Thermography for Seal Contamination Detection in Heat-Sealed Food Packaging
Active Infrared Thermography for Seal Contamination Detection in Heat-Sealed Food Packaging
复制标题
DOI：
10.3390/jimaging2040033
复制
发表时间：
2016-12-01
影响因子：
3.2
通讯作者：
De Ketelaere, Bart
中科院分区：
文献类型：
--
作者：
D'huys, Karlien;Saeys, Wouter;De Ketelaere, Bart
包装可以保护食品免受环境影响，如果包装得当，可以确保整个保质期内的质量和安全。包装质量取决于包装材料和封口或密封的质量。可能危及密封质量的一个常见问题是密封污染的存在，这可能导致密封强度降低，包装失效风险增加和泄漏形成。因此，从生产链中及早发现和清除密封污染的包装至关重要。在这项工作中，脉冲型主动热成像方法使用加热的密封条作为激励源的密封污染检测进行了研究。密封后不久，记录了受污染密封的热图像序列。比较了基于单帧、冷却曲线拟合、热信号重构、脉冲相位热成像、主成分热成像和匹配滤波等6种热图像处理方法的检测性能。高分辨率数字图像用作量化密封污染的参考，并将处理后的热图像映射到这些参考。最低检测限（等效直径0.60 mm）的基础上得到的冷却曲线拟合的方法。此外，该方法的检测性能并不强烈依赖于密封后开始记录热图像的时间，使其成为一种稳健且普遍适用的方法。
Packaging protects food products from environmental influences, assuring quality and safety throughout shelf life if properly performed. Packaging quality depends on the quality of the packaging material and of the closure or seal. A common problem possibly jeopardizing seal quality is the presence of seal contamination, which can cause a decreased seal strength, an increased packaging failure risk and leak formation. Therefore, early detection and removal of seal contaminated packages from the production chain is crucial. In this work, a pulsed-type active thermography method using the heated seal bars as an excitation source was studied for detecting seal contamination. Thermal image sequences of contaminated seals were recorded shortly after sealing. The detection performances of six thermal image processing methods, based on a single frame, a fit of the cooling profiles, thermal signal reconstruction, pulsed phase thermography, principal component thermography and a matched filter, were compared. High resolution digital images served as a reference to quantify seal contamination, and processed thermal images were mapped to these references. The lowest detection limit (equivalent diameter 0.60 mm) was obtained for the method based on a fit of the cooling profiles. Moreover, the detection performance of this method did not depend strongly on the time after sealing at which recording of the thermal images was started, making it a robust and generally applicable method.