Starch Gelation Process Observed by FT-IR/ATR Spectrometry with Multivariate Data Analysis

For directly observing changes related to the gelation process of starch, IR spectra of starch in water while heating were obtained using FT-IR/ATR spectrometry. Relationships between gelation and spectral changes were examined using factor analysis, evolving factor analysis (EFA) and three-way principal component analysis (PCA). Absorption at 3300 and 1610 cm^-1 decreased with temperature but absorption at 1000 cm^-1 increased. The factor score plot patterns of amylose, amylopectin and rice starches were similar but those of potato and corn starches were unique. EFA indicated variances relating to changes caused in starch and water as different factors. Loadings of the starch component 2 in three-way PCA correlated with starch granule sizes.