Post Harvest Applications of Cold Plasma Technology: A Review

Abstract

Plasma is the fourth state of matters which have a wide application in food processing and post harvest technology. Plasma when applied over crops has tremendous effects in improvement in the quality and other post harvest attributes. Application of cold plasma technology could effectively induce desirable changes in its overall quality and diverse physiology. The following review would discuss the application of non-thermal plasma technology to disinfect and decontaminate processed food product and fresh horticultural crops. Horticultural crops which are treated with plasma technology do not show any loss in nutrients. The packaging materials can also be sterilized by using plasma technology. Similarly, the food packed inside a package can also be sterilized without harming the package integrity. Beside that it can also be used to reduce the enzymatic activity of fresh fruits and vegetables and help to modify the food properties. Cold plasma technology can penetrate fungal biofilm and destroy resting fungal spores. This technology can also be harnessed to remove residual toxic pesticide from food products and fresh fruits and vegetables. However, the technology might sound a bit expensive but have a long future in terms of utility.

Green Technology for Reducing Postharvest Losses and Improving the Nutritional Quality of Fresh Horticultural Produce

“…These physiological changes may be desirable or undesirable depending on the type of produce as these changes directly affect eating quality. UV-C treatment has been shown to enhance antioxidant systems for both antioxidant compounds and oxidative enzyme activities in various fresh produce pear [75], mangosteen [76], mangoes [78], broccoli [83,84], leaf vegetables [85], garlic [86], pepino fruit [87], and tomato [88,89]. While many studies have shown that UV-C radiation treatment can induce many bioactive compounds, but some studies have shown that UV-C treatment did not enhance polyphenols, β-carotene, ascorbic acid, chlorophyll contents in persimmon and cucumber [90], and total phenolic content, anthocyanin compounds, and antioxidant activity in grape [81].…”

“…Plasma is commonly known as the fourth state of matter, after gases, liquids, and solids. Plasma is quite like a gas than a solid or liquid, but its property differs from solid, liquid, and gas [86]. Two major types of plasma are differentiated based on thermodynamics: thermal plasma and non-thermal plasma (referred to cold plasma, temperature < 60°C) [86][87][88].…”

“…Plasma is quite like a gas than a solid or liquid, but its property differs from solid, liquid, and gas [86]. Two major types of plasma are differentiated based on thermodynamics: thermal plasma and non-thermal plasma (referred to cold plasma, temperature < 60°C) [86][87][88]. Thus, cold plasma (CP) is selected to apply to various foods including fruit and vegetables to avoid the loss of nutrition and sensory contributions.…”

“…Thus, cold plasma (CP) is selected to apply to various foods including fruit and vegetables to avoid the loss of nutrition and sensory contributions. CP can be generated by many techniques including corona discharge (CD), dielectric barrier discharge (DBD), gliding arc discharge (GAD), microplasma, radio frequency (RF) discharge, plasma spray, plasma needle, and atmospheric pressure plasma jet [86,88]. In all plasma techniques, the feed gas is required to energize into plasma [88].…”

“…When the initial gas is treated with sufficiently high energy, the structure of molecules and intra-atomics is broken resulting in the formation of free electrons, neutrals, and other reactive ion species. The initial feed-in gas for plasma generation can be either a single gas or a mixture of various gases, i.e., carbon dioxide, oxygen, nitrogen, argon, neon, helium, or even air [86,87]. In addition, moisture can be mixed with the feed-in gases [88].…”