Proximate Analysis of Low Glycemic Index Fortified Rice Flours Developed from Different Rice Varieties

Abstract

Rice is a major staple food, but conventional milling and polishing reduce its dietary fibre, micronutrient, and bioactive compound content while leaving starch as the predominant component. The increasing prevalence of impaired glucose regulation and micronutrient deficiencies highlights the need for nutritionally improved staple foods. Incorporating foxtail millet and vitamin–mineral fortification into selected rice varieties may improve their nutritional profile; however, limited information is available on the proximate composition of such fortified rice flour formulations. The present study assessed the proximate composition of fortified rice flours developed from five rice varieties: RNR-15048 (T1), Chempa (T2), Chengalpattu (T3), Matta (T4), and Doppi (T5). Each formulation comprised 80% rice flour, 18% foxtail millet flour, and 2% premix. Proximate analysis was conducted using standard AOAC protocols for moisture, ash, protein, fat, crude fibre, starch, carbohydrate, and energy. The data were statistically analysed using a Completely Randomised Design (CRD). Significant treatment differences (P < 0.01) were observed for all evaluated parameters. Among the formulations, RNR-15048 (T1) showed the most favourable proximate profile, with the highest ash (2.00%), crude protein (7.53%), and crude fibre (10.00%) contents and the lowest starch (61.19%), carbohydrate (79.26%), and energy (350.82 kcal/100 g) values. Matta (T4) had the highest starch (69.97%), carbohydrate (82.49%), and energy (366.40 kcal/100 g) values and the lowest moisture content (8.00%). Crude fat remained low across treatments (0.40–0.80%) but differed significantly among the formulations. The combined effects of varietal composition and fortification with foxtail millet flour and a vitamin–mineral premix may account for the favourable proximate profile of RNR-15048. Because glycemic index and starch digestibility were not directly measured, the findings indicate potential rather than confirmed glycemic benefits.