Effect of Nixtamalization on the Physical Functional and Nutritional Properties of Foxtail Millet Flour

Aims: To investigate the physico-functional and nutritional properties of nixtamalized foxtail millet and compare them with non-nixtamalized millet. Nixtamalization is an ancient processing technique involving the soaking and cooking of grains in an alkaline solution, typically lime water. This process enhances the nutritional profile, flavor, and functional properties of grains, making them more suitable for various culinary applications. Minor millets possess immense nutritional value, comparable to that of wheat, rice, and maize.

Study Design: Experimental design.

Place and Duration of Study: Foxtail millet grain and maize grain were procured from Millet Processing and Incubation Centre (MPIC) PJTSAU, Rajendranagar, Hyderabad and food grade calcium hydroxide chemical was purchased from local market in Hyderabad. This study was concluded during 2023.

Methodology: Maize grain and foxtail millet were nixtamalized and analyzed for physical parameters viz. thousand kernel weight, thousand kernel volume and bulk density. Functional properties of nixtamalized grains such as swelling power, swelling capacity water solubility index, water holding capacity, oil absorption capacity; water absorption capacity and oil retention capacity and nutritional properties like moisture, fat, ash, crude fibre, carbohydrates, protein, energy.

Results: It was found that physical parameters viz. thousand kernel weight, thousand kernel volume and bulk density decreased in nixtamalized maize and foxtail grains. Functional properties of nixtamalized maize and foxtail flours such as swelling power, water solubility index, water holding capacity oil absorption capacity; water absorption capacity and oil retention capacity also increased significantly (p≤0.05) and swelling capacity significantly decreased in nixtamalized maize and foxtail flours. Significant increase (p≤0.05) in moisture NM (34.31%) NF3 (27.51%), ash content NM (49.61%) NF3 (2.37%), carbohydrate content (2.35%) NF3 (2.10%) and fat content NM (35.85%) NF3 (26.30%), crude fibre NM (26. 35%) NF3 (29.22%), energy NM, (3.2%), NF3 (3.56%) in nixtamalized grains was observed while protein value of nixtamalized grains were significantly lower NM (11.76%) NF3 (6.50%) compared to untreated grains.