Use of Plasma in Food Processing
Growing demand of safe and minimally processed food poses challenges to the food processing and supply system. Non-thermal technologies include application of high pressures, pulsed electric field, pulsed light, irradiation, oscillating magnetic field, ultrasonics, ozonation, and plasma processing. Most of these technologies require high initial investments, whereas some are associated with adverse perceptions and/or other constraints, limiting the uses of these commercially viable methods. The highly reactive gas species produced by the electrical discharge is called plasma that possesses electron, photon, ions, free radicals, atoms, and metastables but have overall net neutral charges in its fundamental or excited state. An American physicist, Irving Langmuir, first coined the term plasma in 1928 to narrate the fourth state of matter which abundantly exists in the universe other than solid, liquid, and gas. Plasma is categorized into two different classes on the basis of their generation as high-temperature or fusion plasma and low-temperature plasma.