The effect of thermal processing and different concentrations of resistant starch on X-ray pattern, crystallization kinetics and morphological properties of noodles supplemented with wheat and corn resistant starch

The impact of the substitution of wheat flour with 20, 40 and 60% of wheat resistant starch (WRS type III) and corn resistant starch (CRS type III) on noodle properties was investigated by means of X-ray diffraction, textural profile analysis, physico-chemical properties and microstructure evaluation. The kinetic data of amylose at different concentration of WRC and CRS during baking were investigated in terms of zero order model (ZOM), first-order model (FOM), and parabolic diffusion model (PDM). Furthermore, the kinetic data of crystallinity were fitted to the pseudo-first-order (PFOM), pseudo-second-order model (PSOM), and intra-particle diffusion models (IDM). A ZOM satisfactorily described the experimental data of amylose at different concentration of resistant starch, whereas crystallinity data was ideally fitted to PFOM. According to X-ray pattern, crystallinity of noodle containing CRS and WRS had increasing trend with wheat flour substitution. The hardness, cohesiveness and adhesiveness of the dough diminished remarkably as the resistant starch content increases. With the augment in resistant starch level, the finest noodle cooking time was reduced and furthermore, the noodle cooking loss was significantly increased, while the water uptake and the time needs for cooking the samples, decreased.