7th Asia-Pacific Conference on Plasma Physics, 12-17 Nov, 2023 at Port Messe Nagoya

Surface Analysis of White Grapes treated using Argon Cold AtmosphericPressure Plasma JetAbhijit Mishra1, Ritesh Mishra2, Sushma Jangra1, Shikha Pandey1, and Ram Prakash1,2
1
Department of Physics, Indian Institute of Technology, Jodhpur, India
2
Division of IDRP – Smart Health Care, Indian Institute of Technology Jodhpur, Rajasthan, Indiae-mail (speaker): abhijit.1@iitj.ac.inGrapes, being a significant fruit crop owing to their higheconomic value, with a global production ofapproximately 79.2 million tonnes (FAO, 2018), areperishable and undergo changes in flavour, colour,nutrients, and texture during storage, which can impact
consumer purchasing decisions [1]. Softening is the mostcommon phenomenon in fruit texture changes, and it
occurs during the ripening process and is often associatedwith a decrease in cell wall hardness, causing a reductionin cell wall adhesion, making it easier for microbial toinvade the cell, resulting in rotting and spoilage [2].
Several technologies have been developed to improve thequality and shelf-life of perishable products that includes
Modified Atmosphere Packaging (MAP), Cold-Chain
Storage and Transportation, Ozone treatment andchemical preservatives, etc. [3]. Cold atmospheric plasma(CAP) is a novel quality preservation technology that has
gained attention in the food industry recently due to its
distinctive characteristics and versatile applications [4].
However, in-depth understanding is needed to understandthe induced changes in quality attributes of the treatedGrapes.
The present study focuses on the effect of Argon CAP jet
on the surface properties of white grapes at differenttreatment intervals. The developed cross-field configured
CAP jet is a double dielectric barrier discharge (DBD)
system which generates plasma through a dielectricmaterial tube having dielectric constant 3.7 in which a
copper wire mounted by similar tube acts as the central
power electrode and a thin copper material as the outerring electrode. The central electrode is connected througha bipolar pulsed high-voltage power source, and the outerelectrode is grounded. Argon is used as the working gas at
atmospheric pressure. The plasma discharge is optimized
at different combinations of input parameters like its
applied voltage, frequency, average power consumption
and gas flow rate. The CAP jet generated species areanalysed using Optical Emission Spectroscopy (OES).
Grapes are treated for different time intervals like 1 min,
2 min and 3 min at optimized parameters. The effect ofCAP jet treatment on different physicochemical properties
like change in surface microstructure, hydrophilicity,firmness, chemical structure assessment, change in colour,
Total Soluble Solid (TSS) level, water activity, etc. arecompared between untreated and treated grapes. CAP jet
treatment is found to be effective only on the physicalcharacteristics of the grapes surface and not altering any

chemical compositions. The detailed results obtained will
be presented.
References[1] S. H. Miraei Ashtiani et al., Innovative Food Science& Emerging Technologies, vol. 63, p. 102381, (2020).
[2] Y. W. Pan, J. H. Cheng, and D. W. Sun, Critical
Reviews in Food Science and Nutrition, vol. 61, no. 12,
pp. 1935–1946 (2020)[3] A. Sridhar, M. Ponnuchamy, P. S. Kumar, and A.
Kapoor, Environmental Chemistry Letters 2020 19:2, vol.
19, no. 2, pp. 1715–1735 (2020)[4] F. A. N. Fernandes and S. Rodrigues, Processes, vol. 9,no. 12 (2021)