Influence of Ƴ-irradiation and genotype on the structural and techno-functional properties and microbial quality of Millet flour

Abstract

Barnyard(Echinochloautilis),Finger (Eleusinecoracana), Foxtail (Setaria italic), Kodo (Paspalumsetaceum) Little (Panicum sumatrense),Pearl (Pennisetumglaucum), and Proso(Penicummiliaceum) millets are staple foods for Indian and African diets.Post harvest handling primarily the storage conditions during rainy season leads to significant losses of millets in Asia and Africa.Poor storage conditions during rainy seasons lead to germination and fungal growth due to poor storage infrastructure facilities in Asia and Africa. To prevent food losses and to understand the irradiation influence on biopolymer functionality, the millets were irradiated at a dosage of 2.5 and 5 kGy at 12% and 14% moisture contents and milled to prepare the flour.The flour was analysed for microbial count and changes in structural and functional properties to understand the implications on end-use. Post irradiation, oil absorption, emulsion capacity, and water absorption decreased significantly (p≤0.05), while foaming capacity, emulsion stability, and foaming stability increased. Hunter color values L*, a*, and b* showed different trends with an increase in dosage of irradiation.FTIR studies revealed that there were shifts in the functional groups, primarily a decrease in the intensities of O-H, C-H, and O=C stretches and the bending mode of water.Scanning electron microscopy at 2500x magnification revealed different morphological shapes from spherical, polygonal, and a few spherical granules. In our studies we observed that gamma irradiation decreases the nicrobial count and at the same time deactivates the germinating enzymes.Therefore the irradiation treatment is an affordable and effective methodology to prevent post harvest losses of millets In general, irradiation influenced the millet flour functionality and a decrease in microbial with irradiation , therefore,irradiation can help prevent post-harvestmillet lossesin developing nations. Studies on controlled irradiation can help improve the flour properties for better end use