Multi‐Parametric Fluorescence Spectroscopy for the Detection and Characterization of Plant‐Derived Protein Residues on 316L Stainless Steel

Adsorption of proteins and other biomolecules on stainless steel and other functional metallic surfaces is a key interfacial phenomenon in food processing environments, leading to progressive surface accumulation of organic residues. Their presence can impair the material performance, promote microbial adhesion, complicate cleaning procedures, and ultimately create significant hygiene challenges. In this study, UV–vis fluorescence spectroscopy was evaluated for its suitability in monitoring the adsorption of plant‐derived biomolecules on AISI 316L stainless steel surfaces, using rice protein concentrate in artificial tap water, both in the presence and absence of stearic acid and NaCl. Instrumental parameters were optimized based on multi‐Gaussian peak deconvolution using Bayesian Information Criterion evaluation. This approach enabled robust resolution of overlapping spectral features and improved sensitivity in complex matrices. Fluorescence peak shifts and intensity variations were analyzed to probe protein–alloy surface interactions, providing diagnostic indicators of protein‐induced spectral changes and proposed conformational transitions resulting from protein adsorption. The results demonstrate that fluorescence spectroscopy is a valuable technique for monitoring interfacial protein adsorption and residue accumulation on stainless steel under food‐processing conditions. Overall, the findings provide insights relevant to hygiene control strategies and the optimization of material performance in food‐processing systems.