Research Projects

Millet, also known as "Shreeanna," is still commercially underdeveloped, and modest millet microgreen growth can be pursued to provide a healthy lifestyle and culinary delight. Microgreens are created by the grain germination process, which begins with the quiescent, dry seed absorbing water and then elongating the embryonic axis. However, millet grain has a thick seed coat that stops the seed from absorbing water, necessitating a long soaking time, resulting in undesired microbial contamination and low germination potential. Recently, different methods, such as priming techniques (hydropriming, osmopriming, and halopriming), have been studied to reduce soaking time and improve the germination rate but possess the risk of residues of these components after treatment. Therefore, in this study, pre-treatment of millet with emerging technologies, such as ultrasound in combination with plasma-activated water (PAW), will be employed to modulate the seed surface and enhance the germination rate. The acoustic cavitation produced by ultrasound can aid in creating micropores in the seed surface that can improve the mass transfer rate and enhance the germination potential. Moreover, the reactive species present in PAW (reactive oxygen and nitrogen species) can potentially cause surface etching of the seed coat and induce metabolic activity of enzymes, augmenting the accumulation of soluble sugars and proteins due to starch and protein degradation. The post-harvest quality of microgreens is of significant concern for commercialization. PAW is known to have broad antimicrobial activity due to the action of reactive species (O₃, H₂O₂, NO, NO₂) on microbes by inducing oxidative stress through lipid peroxidation. Therefore, pre-treatment of sprouts and microgreens with PAW can significantly reduce microbial load. and enhance safety during storage. Microgreens are grown under different environmental conditions, but growing media is mainly used for commercial purposes. However, the current project seeks to cultivate microgreens sustainably without soil or medium, as cold plasma technology is known to enhance sprout growth significantly. Microgreens are harvested after the appearance of true leaves, and their shelf life is concise when kept in ambient conditions due to their delicate nature. Therefore, microgreens are considered highly perishable products. The demand for minimally processed food has increased, and scientific information on the effect of PAW on shelf life during different storage conditions is limited. Thus, the present project shall provide a deeper understanding of the effect of PAW technology on both pre-harvest and post-harvest quality of millet microgreens. Non-destructive methodologies, such as NIR spectroscopy, will be employed to detect early changes in the composition of the microgreens indicative of microbial activity and aging. This data can be integrated into predictive microbiology models to determine the shelf-life of microgreens.