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Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce
Published on: October 18, 2010
A smart colorimetric film coupling deep eutectic solvents and deep learning for real-time Salmon freshness monitoring
Jialing Li1, Haibo Xu2, Jingru Chang2
1State Key Laboratory of Marine Food Processing and Safety Control, National Engineering Research Center of Seafood, Academy of Food Interdisciplinary Science, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China; Dalian Key Laboratory for Precision Nutrition, Collaborative Innovation Center of Seafood Deep Processing, Dalian Xinghaiwan Laboratory, School of Information Science and Engineering, Dalian Polytechnic University, Dalian 116034, Liaoning, China.
Abstract:
Effective freshness monitoring is essential for aquatic products to ensure food safety and reduce waste. To overcome the limitations of stability and sensitivity in colorimetric films, we developed a novel composite film by integrating a tannic acid-Fe2+ (TF) chelate with deep eutectic solvents (DESs) in a polyvinyl alcohol matrix. The TF chelate served as multifunctional indicator, providing distinct color responses to NH₃, DMA, and TMA while enhancing hydrophobicity, UV-blocking, and thermal stability. DESs incorporation significantly improved mechanical properties (elongation at break up to 600%) and drastically enhanced sensitivity, enabling visible color changes within 1 min due to increased surface roughness (1.78 to 3.97 nm), hygroscopicity (1.8% to 5.6% at 33% RH), and water vapor permeability (0.4 to 0.8 g·mm/(m2·h·kPa)). In salmon monitoring, the film showed clear color transitions. Deep learning-assisted analysis achieved over 97% accuracy in freshness classification. Overall, the films show strong potential for freshness monitoring of aquatic products.
