A multivariate study of the physicochemical and functional characteristics of native and pregelatinized gluten-free flours and chia expeller

Abstract

The high demand for gluten-free foods and consumers’ preference for healthier diets drivethe search for raw materials with suitable properties for preparing these foods. This studyutilized a multivariate statistical approach to analyze the physicochemical and functionalproperties of rice, buckwheat, green pea, and yellow pea flours in both their native andpregelatinized forms and chia expeller. Principal component analysis (PCA) was appliedto the flours and chia expeller data set. The score plot depicted the variations among thesamples, revealing the correlation patterns between the variables. PC1, 2, and 3 explain44.0, 23.2, and 17.2% of the variability, respectively, describing a total of 84.4% of thevariance. PC1 allowed separating the chia expeller from the other flours, whereas PC2distinguished pea flour from rice flour. By considering PC1, chia expeller was associatedmainly with a high content of fatty acids, crude fiber, and water absorption capacity,water holding capacity, and swelling capacity. These characteristics can be attributed tothe oil and mucilage present in chia expeller. Regarding the other flours, they exhibitedmoderate to high luminosity, moisture content, and carbohydrate levels. ConcerningPC2, pregelatinized rice flour displayed a high absorption capacity of organic moleculeswhereas the pea flours were related to the least gelation concentration, high acidity,bulk, and tapped density, yellow color, oil-holding capacity, emulsifying activity, emulsionstability, and protein content. Thus, this multivariate analysis visualized the associationbetween variables to characterize the analyzed flours and chia expeller, with potentialapplication in gluten-free foods.