Toward the understanding of the interfacial dairy fouling deposition and growth mechanisms at a stainless steel surface: A multiscale approach

• Published in: Journal of colloid and interface science Vol. 404; pp. 192 - 200
• Main Authors: Jimenez, M., Delaplace, G., Nuns, N., Bellayer, S., Deresmes, D., Ronse, G., Alogaili, G., Collinet-Fressancourt, M., Traisnel, M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 15.08.2013; Elsevier
• Subjects: AFM; Amorphous calcium carbonate; atomic force microscopy; Calcium; calcium carbonate; Calcium Carbonate - chemistry; Chemical and Process Engineering; Chemistry; Deposition; Engineering Sciences; EPMA; Exact sciences and technology; Food engineering; Fouling; General and physical chemistry; Growth mechanism; heat exchangers; Interface; Life Sciences; mass spectrometry; Microstructure; Milk Proteins - chemistry; Pilots; Protein Folding; roughness; SIMS; Stainless steel; Stainless Steel - chemistry; Stainless steels; Surface physical chemistry; Surface Properties; ToF; Whey; Whey protein; X-radiation; X-rays; β-Lactoglobulin; Fouling; Calcium; β-Lactoglobulin; Stainless steel; Growth mechanism; AFM; ToF; SIMS; Whey protein; Interface; Amorphous calcium carbonate; EPMA; Atomic force microscopy; Chemical analysis; Microanalysis; Lactoglobulins; Calcium carbonate; Deposition; AMORPHOUS CALCIUM-CARBONATE; WHEY-PROTEIN; beta-Lactoglobulin; HEAT-EXCHANGE APPARATUS; TEMPERATURE; KINETICS; INDUCED STRUCTURAL-CHANGES; AGGREGATION; MILK
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2013.04.021

[Display omitted] •Multiscale approach of dairy fouling on stainless steel surface.•Nano-thick fouling layers investigation.•Influence of interface microstructure on fouling deposition.•Proposition of dynamic growth fouling mechanisms.•Competition between protein and calcium deposition. The microstructures of two dairy fouling deposits obtained at a stainless steel surface after different processing times in a pilot plate heat exchanger were investigated at different scales. Electron-Probe Micro Analysis, Time-of-Flight Secondary Ion Mass Spectrometry, Atomic Force Microscopy, and X-Ray Photo-electron Spectroscopy techniques were used for this purpose. The two model fouling solutions were made by rehydrating whey protein in water containing calcium or not. Results on samples collected after 2h processing show that the microstructure of the fouling layers is completely different depending on calcium content: the layer is thin, smooth, and homogeneous in absence of calcium and on the contrary very thick and rough in presence of calcium. Analyses on substrates submitted to 1min fouling reveal that fouling mechanisms are initiated by the deposit of unfolded proteins on the substrate and start immediately till the first seconds of exposure with no lag time. In presence of calcium, amorphous calcium carbonate nuclei are detected in addition to unfolded proteins at the interface, and it is shown that the protein precedes the deposit of calcium on the substrate. Moreover, it is evidenced that amorphous calcium carbonate particles are stabilized by the unfolded protein. They are thus more easily trapped in the steel roughnesses and contribute to accelerate the deposit buildup, offering due to their larger characteristic dimension more roughness and favorable conditions for the subsequent unfolded protein to depose.