Nutritional, Phytochemical, and Rheological Profiles of Different Oat Varieties and Their Potential in the Flour Industry

Abstract

The purpose of this paper is to evaluate from a nutritional, phytochemical, and rheological point of view different varieties/lines of oats cultivated in Romania. In this sense, the proximate composition (proteins, lipids, mineral substances, starch, and carbohydrates), the total polyphenols content (TPC) of individual polyphenols and macro and microelements of 20 oat varieties/lines were determined. In order to evaluate the potential for use in the flour industry (pasta, bread, and biscuits)., a variety of oats with optimal nutritional properties and active principles was used to obtain oat/wheat composite flours in different proportions (10–30% oat flour) and subjected to rheological analysis using the Chopin Mixolab test (Chopin Technologies, Paris, France) The results showed a protein content between 14.36–17.08%, lipid content between 6.01–9.03%, starch between 44.13–52.95%, total mineral substances between 0.93–1.65%, carbohydrates between 65.16–69.32% and energy value between 389.81–409.86 kcal/100 g. The TPC content varied between 614.76–1244.58 µgGAE/g, and the average values of individual polyphenols were between 1.87 μg/g (rosmarinic acid) and 28.18 μg/g (gallic acid). Regarding the macroelements content, potassium (K) was the major element (203.19 μg/g), followed by calcium (Ca) (181.71 μg/g) and magnesium (Mg) (105.79 μg/g). The level of microelements varied between 3.02 μg/g for nickel (Ni) and 60.25 μg/g for iron (Fe). Multivariate data analysis PCA was used to correlate the obtained data. The rheological analysis using the MIXOLAB system proved that, from the point of view of technological properties, composite flours from a mixture of 10–30% oat and wheat flour are the best for obtaining biscuit dough, compared to pasta or pan bread. Following the study and based on nutritional, phytochemical and rheological results, line 2511 was selected as optimal for use in obtaining hypoglycemic flour foods for people with diabetes.