Micro-computed tomographic and proton NMR characterization of cooked noodles and their correlation with conventional methods

Abstract

Microcomputed tomography (micro-CT) and proton NMR were applied to quantitatively characterize the structural changes of noodles depending on cooking times, and then compared with conventional methods. In the micro-CT analysis, the cooked and uncooked portions of the noodles were distinctly visualized depending on their density difference, and their 3-dimensional images were successfully utilized to calculate the degree of cooking. In terms of water mobility, three distinct water populations were observed in the cooked noodles. All the T2 relaxation times had a tendency to increase with increasing cooking times, while the proportions of weakly bound water and tightly bound water varied. The noodles cooked for longer times exhibited a softer texture and higher cold initial/lower final viscosities. Pearson correlation and principal component analysis demonstrated that the parameters obtained by micro-CT and proton NMR were well-correlated with water absorption, firmness, and pasting properties (cold initial and final viscosity) from the conventional methods.