Microstructural Changes in Instant Noodles During Production via Triple Staining and Confocal Laser Scanning Microscopy and Scanning Electron Microscopy

Abstract

Confocal Laser Scanning Microscopy (CLSM) was used to study changes in microstructure throughout the process of instant noodle production. Multiple staining of acridine orange, fluorolink Cy-3 and sulforhodamine was applied in order to differentiate protein, starch and lipid, respectively, in the same image. Scanning Electron Microscopy (SEM) was also applied, complementarily, to contribute stereoscopic images. The microscopic data obtained from triple-labeled samples examined by CLSM were found to correspond to the stereoscopic SEM micrographs. Morphological changes and microstructural arrangement of starch granules and protein matrix, and the presence of lipids were found to respond to different regimes of process: addition of water, inputs of mechanical force and heat and introduction of frying. Thus, triple staining, via CLSM, could be regarded as a potential tool for monitoring microstructural differences resulting from varied processing conditions.