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Research ArticleEffects of Multihollow Surface Dielectric Barrier DischargePlasma on Chemical and Antioxidant Properties of Peanut

Gebremedhin Gebremariam Gebremical 12 Shimelis Admassu Emire2

and Tarekegn Berhanu3

1Department of Food Process Engineering and Postharvest Technology Ambo University Ambo Ethiopia2School of Chemical and Bioengineering Addis Ababa Institute of Technology Addis Ababa Ethiopia3Addis Ababa Science and Technology University Addis Ababa Ethiopia

Correspondence should be addressed to Gebremedhin Gebremariam Gebremical gebremedhingebremariamaaiteduet

Received 22 November 2018 Accepted 6 January 2019 Published 29 January 2019

Guest Editor Vladimır Scholtz

Copyright copy 2019 Gebremedhin Gebremariam Gebremical et al is is an open access article distributed under the CreativeCommons Attribution License which permits unrestricted use distribution and reproduction in any medium provided theoriginal work is properly cited

An experiment was conducted to investigate the eects of atmospheric pressure plasma generated by multihollow surfacedielectric barrier discharge on chemical and antioxidant properties of peanut Multihollow surface dielectric barrier discharge is anovel plasma device applicable in food industry applications due to the capacity of the generated plasma to treat the surface of foodwithout changing the quality Peanut seeds were exposed to the multihollow plasma for dierent plasma power (10ndash40W) air owrate (05ndash20 lmin) and time (1ndash15min) e fatty acid prole peroxide value acid value moisture content total polyphenolsand antioxidant activity were evaluated during cold plasma treatmente result revealed that due to the variation plasma powertreatment time and air ow rate caused a decrease in unsaturated fatty acid and moisture content and increased saturated fattyacids peroxide value acid value and total polyphenols of the peanut

1 Introduction

Peanuts (Arachis hypogaea L) are a globally importantoilseed valued as a source of high-quality cooking oil crudeprotein crude fat crude ber water ash total sugar aminoacids fatty acids vitamins minerals phytosterol resvera-trol squalene and other antinutritional factors [1] andappreciated worldwide as an aordable avorful serving asa primary ingredient for peanut butter confections andnutritional bars among other nished products It is widelyused as an economic food enhancement to counter mal-nutrition owing to its high nutritional value [2] Howeverthe aforementioned characteristics led the peanut to becomesensitive tomolds contamination in the whole supply chains[3] and other biotic and abiotic stresses constrain pro-duction and use of peanut [4 5] Dierent microorganismsinfect peanuts and cause spoilage leading to the productionof toxic metabolites [6ndash8] Various methods have beenapplied to decontaminate the growth of molds in peanut

such as conventional and nonthermal treatments but noneof these methods oers a complete control of toxigenicmolds

A lot of nonthermal technologies have been investigatedand applied in food industries to assure and improve thequality of the food e use of nonthermal surface de-contamination processes and surface treatment is desirablefor a variety of food products in particular for those inwhich it is important to heat sensitive agricultural productsAmong those nonthermal technologies plasma is one of thelatest green technologies used now a days around the worldfor various applications [9 10]

According to Fridman et al [11] plasma is often referredto as the fourth state of matter comprised of several excitedatomic molecular ionic and radical species coexisting withnumerous reactive species including electrons positive andnegative ions free radicals gas atoms molecules in theground or excited state and quanta of electromagnetic ra-diation (UV photons and visible light) Plasma can be

HindawiJournal of Food QualityVolume 2019 Article ID 3702649 10 pageshttpsdoiorg10115520193702649

generated using any kind of energy which can ionize thegases such as electrical thermal optical and radioactive andX-ray electromagnetic radiation However electric orelectromagnetic fields are widely used for cold plasmageneration [12] Plasma can be generated at low or highpressure but plasma generated at atmospheric pressure is ofinterest to the food industry because it does not requireextreme process conditions [13] Cold Plasma is also knownas nonequilibrium plasma because of its low gas temper-ature of lt70degC because the applied energy leads to an elasticcollision of the gas particles atoms and electrons +e gasparticles are less energetic than the electrons in the dischargewhere the heavy particles have kinetic temperatures close toambient because the transfer of kinetic energy to otherparticles in such a way that the cooling of the unchargedparticles and neutral ions is more rapid than the energytransfer from the electrons [11 14 15]

Cold plasma is a better alternative to other existingsurface decontamination methods due to operation at at-mospheric pressure low-temperature long operative du-ration and economical and simple systems [16] and it is anovel and green food preservation technology and has onlybeen applied at very small scales [17] +is technology isgradually finding acceptance among food researchers for thesurface sterilization but the effect of cold plasma on thesensitive constituents of foods mainly lipids vitamins andbioactive compounds and the physical quality of theproduct being treated not addressed [13]

Atmospheric cold plasma surface treatment processoffers novel food preservation properties and has been testedwith different plasma setup and gas sources in differentcereal grains [8 18] peanuts [6 8 19 20] dairy [21] fruitsand vegetables [22] meat [23ndash25] and spices [26 27] butnone of them have investigated the synergetic effect of coldplasma operating conditions (plasma power air flow rateand treatment time) on the quality of the treated foodproduct

Numerous researches have been done to investigate theeffects of plasma on food constituents and various chemicalreactions are induced by plasma but there has been spec-ulation on the free radical formation when fatty foods andwith high antioxidant and polyphenol compounds are ex-posed to plasma energy Cold plasma can generate reactiveand free radical species and these species that have strongoxidation capacities Treating high lipid-containing mate-rials with cold plasma could lead to lipid and consequently todevelopment of off-flavor and off-odor and in loss of naturalantioxidants and caused the formation of many volatilesrelated to lipid oxidation [24] Peanut contains the highpercentage of mono- and polyunsaturated fatty acids and thelow percentage of saturated fatty acids [1]

Little information is available about the synergistic in-fluence of cold plasma operation conditions (plasma powerair flow rate and treatment time) peroxide value acid valuefatty acid profile antioxidant activity total polyphenols andmoisture contents of peanuts +erefore the current ob-jective was to study the influence of multihollow surfacedielectric barrier discharge plasma operating conditions onchemical and antioxidant properties of peanut

2 Experimental Details

21 Chemicals and Samples n-Hexane methanol 95ethanol potassium hydroxide sodium thiosulphate po-tassium iodide chloroform glacial acetic acid 22-diphenyl-1-picryhydrzyl radical (DPPH) FolinndashCiocalteu sodiumcarbonate starch and gallic acid A domestic commercialpeanut (Roba variety) was obtained from the Were ResearchCenter Oromia Ethiopia

22 Plasma Treatment of Peanuts Plasma surface modifi-cation of peanuts was carried out using a special reactor forplasma treatment of small peanut samples +e rector wasbased on commercial coplanar-type multihollow surfacedielectric barrier discharge unit for which the detail char-acteristics and properties were reported by [28] A schematicdraw of the experimental setup is shown in Figure 1Multihollow surface dielectric barrier discharge plasma(MSDBD) is composed of two planar metal electrodes atdistance 05mm both embedded in alumina ceramic +eentire surface is perforated by creating the18times189mm(sim34 cm2) Multihollow surface DBD plasma was generatedby a sinusoidal alternate current (sim27 kHz) high-voltage(10 kV) power source An MSDBD unit was embedded in afeed chamber enabling the plasma generation at a certainflow of plasma forming gas

Plasma treatment of peanuts was done at varied treat-ment conditions Total input power monitored by a com-mercial wattmeter was 10ndash40W +e flow rate of ambientair with humidity 20ndash30 was controlled by the thermalmass flow controller RED-Y in the range (05ndash20 Lmin)+e treatment time was varied from 1ndash15min based onrotatable central composite design IR thermometer FLUKE62 MAX 3M DROP waterdust resistance IP54 with thetemperature range minus30 to 500degC was used to measure thetemperature of the ceramic during the experiment Sixpeanuts were treated by plasma in one batch +e peanutswere mechanically moved and turned around by inert plasticrod during the plasma treatment to provide a homogeneoussurface treatment of peanuts +e samples were taken fromthe plasma field after treatment and the treated peanutswere cooled to room temperature packed in polyethylenebags and kept at 4degC for further analysis

23 Sample Preparation for Extraction +e cold plasma-treated and the untreated peanut seeds were milled(High-Speed Universal Disintegrator (FW100) GrinderChina) with a speed of rotating knife (2400 rpm) and passedthrough a mesh size 16 sieve to obtain identically sizedparticles and then was retained in a sealed bag in a re-frigerator (1-2degC) until use Milled peanut seed particle size isimportant to facilitate analyses of mass transfer during theextraction of oil and antioxidant

24 Extraction Methods +e extraction was performed induplicate with solvent n-hexane (99 purity) An au-tomated Soxhlet set (+e Soxhlet extractor SXT-06

2 Journal of Food Quality

Shaanxi China) was used to extract peanut oil Toachieve this 5 g of sample was packed in a cartridgeplaced inside a 250 mL extractor device +e sample wasextracted for 8 h +en extra solvent form sample oil wasremoved by the rotary vacuum evaporator +e extractedsolvent was stored in a brown bottle in the refrigeratorfor further analysis

25 Extraction of Antioxidant Components +e plasma-treated peanut seeds were defatted first with n-hexane(10 wv) using a Soxhlet extraction unit for 8 h +edefatted samples were then air-dried and extracted withmethanol (100mL) using an incubator shaker (+ermoShaker Incubator Model THZ-103B China) All sus-pensions were then filtered through a Whatman No 1filter paper and the residues re-extracted twice each timewith an additional 100mL of the same solvent +e fil-trates were combined and the solvent evaporated underreduced pressure using a rotary evaporator (Eyela ModelN-1000) at 40degC +e methanolic extracts were used forthe determination of total polyphenol and antioxidantactivity

251 Extraction of Peanut for Analysis of the Antioxidantand Polyphenols Samples were extracted based on theprocedures used by Bishi et al [29] Briefly five grams ofdried groundnut powder was extracted by stirring with 50mlof methanol at 25degC at 150 rpm for 24 h using the tem-perature shaker incubator (ZHWY-103B) and then filteredthrough Whatman No 4 paper +e residue was thenextracted two wises with the addition of 50mL methanol asthe above procedure +e combined methanol extracts wereevaporated at 40degC to dryness using a rotary evaporator(Stuart R3300) +e crude extracts were weighed to calculatethe yield and redissolved in methanol at the concentration of30mgml and stored in a refrigerator (minus4degC) until used forfurther work

252 Measurement of Antioxidant Activities and TotalPolyphenol

(1) Total Polyphenols Contents (TPC) Determination Amodified FolinndashCiocalteu procedure as described by [30]was used for the determination of total polyphenol contentsSamples (01mL) were mixed with 10mL of the FolinndashCiocalteu reagent (previously diluted with distilled water 1 10 vv) and the reaction was terminated using 1mL of 75sodium carbonate +e mixture was vortexed for 15 sec forcolor development After 30min incubation at room tem-perature (28plusmn 1degC) the absorbance was measured at 765 nmusing a UV-Vis spectrophotometer (PerkinElmer Lamda950 UVVisNIR) +e standard curve was prepared usinggallic acid standard solutions of known concentrations alinear calibration graph (Figure 2) was constructed withgallic acid concentrations of 20 50 100 150 200 and250 microgmL and the results were expressed as mg gallic acidequivalent100 g sample

TPC C times VM

(1)

where TPC total polyphenol content(mggm) C con-centration of gallic acid (mgmL) V volume of extract inassay (mL) and Mmass of pure plant methanolic extract(gm)

253 Free Radical Scavenging Assay (DPPH) +e effect ofmethanol extracts on DPPH radical was estimated accordingto Win et al [31] A 0004 freshly prepared solution ofDPPH radical solution in methanol was prepared and then4mL of this solution was mixed with methanol extract(40 microL) of the sample Finally the samples were incubatedfor 30min in the dark at room temperature Scavengingcapacity was read by spectrophotometer (PerkinElmerLamda 950 UVVisNIR) by monitoring the decrease inabsorbance at 517 nm +is absorption maximum wasfirst verified by scanning freshly prepared DPPH from

Plasma

PeanutFence

HV

Ambientair flow

Holes

Electrodes

Figure 1 Multihollow surface DBD electrode setup

Journal of Food Quality 3

200ndash800 nm using the scan mode of the spectrophotometerFree radical scavenging activity DPPH in percent () wasthen calculated

radical scavenging activity() Ao minusA1( 1113857

Aolowast 100 (2)

where Ao is the absorbance of the control and A1 is theabsorbance of the sample

26 Moisture Content Before and after plasma treatmentwhole peanut from treatment (triplicate) was dried in aforced air oven at 130degC for 6 hours [32] +e weight dif-ferences before and after oven drying will be used to cal-culate moisture content (MC dry weight)

27 Acid and Peroxide Values Acid value in mgKOHgminus1 oiland peroxide value in mEqO2 kgminus1 oil were determinedaccording to standard methods (AOAC 2010)

28 Fatty Acid Determination +e lipid fraction of peanutseed oil samples was extracted and fatty acids methyl esterswere prepared [33] and the fatty acid profile was determinedby gas chromatography with a mass spectrophotometer(GC-MS)

29 Statistical Analysis Data were subjected to the analysisof variance test (one-way ANOVA) using the JMP 701 SASInstitute Inc 2007 software computer package A com-parison test on treatment means was conducted using thepost hoc Tukey test at (plt 005) differences with 95confidence level

3 Results and Discussion

31 Fatty Acid Profiles Surface oxidation and developmentof undesirable changes may occur in food from extremedoses of cold plasma and cold plasma generates free radicalsand reactive species that may modify the functions of fattyacids inducing lipid oxidation [15] However several au-thors have reported that atmospheric cold plasma treatmentdid not cause any negative effects on the chemical quality offood products

Table 1 shows fatty acid compositions of peanut oilsvariations depending on the cold plasma conditions +e

fatty acids identified from untreated (control) peanut oilwere 1334 palmitic acid (C16 0) 447 stearic acid(18 0) 4346 oleic acid (C18 1) 3256 linoleic acid (18 2) 135 arachidic acid (20 0) 139 gadoleic acid (C20 1) and 289 behenic acid(22 0) +is is in agreement withpreviously reported data [1 34] +e major fatty acids of theunsaturated fatty acids suggest that the peanuts oil is highlynutrient +e ratio of oleic-to-linoleic acid (OL) is a qualityindex employed to decide peanut shelf-life and oil stabilityranging from 1 to 15 15 to 90 and above 90 classified asnormal mid and high-oleic type respectively [35] +epresent study was carried out with normal oleic peanuts(OL 1335) +e total saturated fatty acids and unsatu-rated fatty acids in oil extracted from nonplasma-treated(control) samples of peanut seed oil was 2192 and 7741respectively

Palmitic acid contents of all treatments ranged from1334 (control) to 1523 (cold plasma treated)+is typeof fatty slightly increased in all cold plasma operatingconditions but there were no significant (pgt 05) differencesbetween all samples (Table 1) Stearic acid contents of un-treated and cold plasma treated peanut samples were foundincreased but utmost nonsignificant (pgt 005) in all ex-periments In addition while oleic acid contents of untreatedpeanut oil samples change between 4347 (control) and3574 (plasma treated) linoleic acid contents of peanut oilsranged between 3256 (control) and 2449 (plasmatreated)

Oleic and linoleic acid content was decreased and sig-nificant (plt 005) difference was observed at differentplasma operating conditions (plasma power air flow rateand treatment time) +e same result was reported byAlbertos et al [36] the cause might be reaction produced bythe H and OH plasma species Gadoleic acid (C20 1) is oneof the unsaturated types of fatty acid and occurs in minorproportions During this experiment its amount was de-creased but there was no significant (pgt 005) differencethroughout the experiments as shown in Table 1 Significantincrease in behenic and arachidic acids at various plasmaparameters rates in peanut seed oils and significant differ-ence (plt 005) was observed between same treatmentsGenerally a slight increase in saturated fatty acids and adecrease in unsaturated fatty acids were observed during theexperiment (Table 1) +e results at 25W 10 Lmin and1min were similar to the control as shown in Table 1 +ismight be the reaction between the sample and the energeticparticles especially oxygen reacting species from plasma wasshort thus leading fatty acid profiles to remain unaffected

+e available studies on the effects of cold plasma onlipids in different food products are very limited Howeverbased on the reported studies treatment time and plasmagas could be considered as critical factors affecting lipidoxidation [37] According to Cammerer and Kroh [38]conventional roasting at 120ndash160degC for long time treatmentthe structure of lipid storage cells is damaged and oil ex-posure to oxidation rate increase but as indicated in Fig-ure 3 in this study the variation of temperature the ceramicof the cold plasma was below 80degC therefore atmosphericcold plasma would significantly decrease the risk of oil

002040608

112

0 50 100 150 200 250 300Concentration (microgmL)

Abso

rban

ce at

760

nm

y = 0004x + 00917R2 = 09984

Figure 2 Gallic acid standard curve for the calculation of totalpolyphenols content


exposure to thermal oxidation +e changes in fatty acidcompositions by application of cold plasma could be due tothe detrimental effect of the reactive species of cold plasma[21] Recently Sarangapani et al [39] have indicated thatcold plasma oxidation of lipids

Plasma treatment produces free radicals such ashydroperoxyl radicals superoxide radicals and singlet ox-ygen that attack unsaturated fatty acids which causes todecreases and increased total saturated fatty acids gradually[21] According to another study by Mexis and Kontominas[40] monounsaturated fatty acids as opposed to poly-unsaturated fatty acids were preferentially attacked byoxygen to produce primary and secondary oxidationproducts under gamma irradiation Irradiation caused asignificant gradual decrease in the unsaturated fatty acidcontent and a significant saturated fatty acid content in-crease as irradiation dose increased in sesame seeds [41]

Another study suggested that the decrease in unsaturatedfatty acids during the irradiation exposure of oil was mainlydue to a molecular structure change in fatty acids [42]

32 Acidity Value (AV) Acidity value is an indicator foredibility of oil and suitability for industrial use and anyextreme change could lead to an unwanted influence on thesensory acceptability and shelf-life of the treated foodproduct Peanut is a high oil content product (50ndash55) withhigh unsaturated fatty acids which are susceptible to oxi-dation [43 44] +e oil extracted from untreated (control)peanut seeds has an acid value of 082mg KOHgminus1 (Table 2)which is already in use for edible purpose and this fallswithin the recommended by Alimentarius codex [45] Re-sults obtained from this work indicated that the acid value ofthe peanut oil corresponds to low levels of free fatty acids

Table 1 Mean values comparison of fatty acid profiles of the cold plasma-treated peanut (plt 005)

Plasma treatment condition C16 0 18 0 C18 1 C18 2 20 0 20 1 22 01 34W 16 Lmin 12min 1432plusmn 184a 712plusmn 035a 3819plusmn 163c 2800plusmn 141bcd 409plusmn 014abc 108plusmn 025a 573plusmn 066ab2 34W 16 Lmin 4min 1422plusmn 035a 614plusmn 121ab 3842plusmn 071bc 2906plusmn 014abc 399plusmn 014abc 106plusmn 021a 5plusmn 001abc3 25W 10 Lmin 15min 1400plusmn 014a 624plusmn 035ab 3836plusmn 205bc 2576plusmn 092bcd 573plusmn 085a 029plusmn 028a 554plusmn 064ab4 25W 20 Lmin 8min 1508plusmn 021a 701plusmn 002a 3712plusmn 297c 2504plusmn 092bcd 489plusmn 028abc 054plusmn 064a 753plusmn 046a5 34W 4 lmin 4min 1523plusmn 042a 703plusmn 019a 3740plusmn 071c 2662plusmn 085bcd 403plusmn 007abc 097plusmn 007a 693plusmn 134a6 10W 10 Lmin 8min 1445plusmn 078a 607plusmn 014ab 3939plusmn 071abc 2993plusmn 132ab 356plusmn 049bc 106plusmn 014a 384plusmn 116bc7 25W 10 Lmin 8min 1432plusmn 046a 640plusmn 070ab 3938plusmn 071abc 2698plusmn 067bcd 342plusmn 062c 105plusmn 013a 566plusmn 049ab8 25W 05 Lmin 8min 1399plusmn 007a 710plusmn 028a 397plusmn 086abc 2659plusmn 078bcd 343plusmn 062c 098plusmn 007a 653plusmn 057a9 16W 4 Lmin 4min 1413plusmn 042a 542plusmn 050ab 3760plusmn 064c 2968plusmn 071ab 404plusmn 014abc 096plusmn 011a 348plusmn 057bc10 25W 10 Lmin 1min 1324plusmn 035a 451plusmn 035b 4327plusmn 099ab 3246plusmn 085a 160plusmn 026d 126plusmn 028a 287plusmn 019c11 16W 16 Lmin 4min 1411plusmn 021a 637plusmn 042ab 3689plusmn 028c 2941plusmn 064abc 443plusmn 071abc 114plusmn 021a 503plusmn 006abc12 16W 16 Lmin 12min 1429plusmn 035a 719plusmn 096a 3888plusmn 123abc 2626plusmn 12bcd 407plusmn 021abc 052plusmn 052a 668plusmn 054a13 40W 10 Lmin 8min 1506plusmn 009a 698plusmn 014a 3574plusmn 121c 2449plusmn 204d 534plusmn 071ab 032plusmn 085a 74plusmn 069a14 34W 4 Lmin 12min 1427plusmn 103a 741plusmn 049a 3685plusmn 047c 2558plusmn 20bcd 523plusmn 042ab 011plusmn 017a 745plusmn 071a15 16W 4 Lmin 12min 1500plusmn 002a 750plusmn 069a 3627plusmn 094c 2499plusmn 007cd 504plusmn 006abc 048plusmn 057a 692plusmn 049a16 Control 1334plusmn 085a 447plusmn 032b 4346plusmn 072a 3256plusmn 113a 135plusmn 01d 139plusmn 049a 289plusmn 027c

All values are meanplusmn SD andashdValues in the same column with different superscripts are significantly different

80

60

40

20

0

Tem

pera

ture

of t

he ce

ram

ic (deg

C)

P1 P2 P3 P4 P5 P7P6 P8 P9 P10

P11

P12

P13

P14

P15

Plasma operating conditions

Heating map1

3

5

7

9

11

13

15

Plas

ma o

pera

ting

cond

ition

s70

60

50

40

30

Cer

amic

tem

pera

ture

(degC)

303828306426347033292831476229

Figure 3 Temperature of ceramic at different plasma operating conditions


present in the oil in most experiment trials which suggestedlow levels of hydrolytic and lipolytic activities in the oil

+e acid value of the oil extracted from noncold plasma-treated peanut oils samples increased from 082plusmn 022 to316plusmn 012mg KOH gminus1 oil during the treatment+e increasein the acid value of oil during the treatment might be due toslight and random hydrolysis of triglycerol molecules to freefatty acids and diacylglycerols [46] Recently Kim et al [47]evaluated the physicochemical characteristics of milk that wastreated with cold plasma and reported an increase in acidityWhen peanut seeds were treated with optimum cold plasmacondition rates the fatty acid was oxidized rapidly and theAV would increase It is clear that no significant difference(pgt 005) was observed between treated and untreated groups(Table 2) except at extreme conditions +e results demon-strate that the peanuts treated under the optimal cold plasmaconditions were stable in the acid value

33 Peroxide Value (PV) Lipid oxidation is a complexprocess involving free radical chain mechanisms formingfatty peroxidation products [48] and peroxide (PV) im-portant parameters for elucidating the peanut oil quality andassessing the oxidation extent [49] Since cold plasma isoften considered as an advanced ionized new technology itis important to analyze its influence on the lipids present inthe fatty foods As Table 2 indicates the PV produced fromcontrol and cold plasma-treated peanut oil was almost below10 mEqO2 kgminus1 oil except for few experiment trials and it islow as the Codex Alimentarius Commission stipulatedpermitted maximum peroxide levels of 10 mEqO2 kgminus1 oil[45] As the plasma power and treatment time increased theair flow rate decreased the overall lipid oxidation increasedand significantly different (plt 005) from other plasmaoperating conditions

Different researchers have done different experimentsand have reported different results After cold plasmatreatment in fresh and frozen pork [50] beef jerky [25] andraw pork [51] have observed no significant effect on lipid

oxidation However in [52] an increase has been reported inlipid oxidation in fresh pork and beef after treating them foran extended time period Recently Albertos et al [36] havereported that cold plasma treatment led to a significant lipidoxidation in fresh mackerel fillets It has been reported in[47 52] that plasma treatment of meat products increasedlipid oxidation when subjected to higher treatments

A comparison of different voltages and treatment timeshowed both variables increased the rate of oxidation [36]Joshi et al [53] also suggested that lipid oxidation is pro-portional to the amount of plasma energy applied VanDurme et al [54] also revealed that cold plasma caused theformation of many volatiles related to lipid oxidationDuring this study the peroxide value of the oils testedsignificantly increased (plt 005) (an increase from 156 to1395 mEqO2 kgminus1 oil) which might be attributed the lack ofoptimum operating conditions of cold plasma Cold plasmacan generate reactive (free radicle) species that have strongoxidation capacities and that cause lipid oxidation [24]+irumdas et al [55] reported that the main problem en-countered was an increase in PV which is at higher powerand treatment time Similar results were observed in the caseof our results cold plasma-treated peanuts samples

34TotalPolyphenols Polyphenols are common constituentsin plant products and important antioxidants which arecontained in large amounts in peanut [56] and used asantifungal infections in peanuts Polyphenols play a role in theprevention of degenerative diseases mainly cardiovasculardiseases and cancers with their antioxidative properties [57]

In this study polyphenols were used as indicators toassess the degree of oxidation by cold plasma Total poly-phenol of untreated and cold-plasma treated peanut seeds isshown in Table 2 +e total polyphenol content of untreated(control) peanut seeds was 20023 mg Gallic acid 100minus1 +isamount is similar to that in the literature [58ndash60] In thisstudy there was a variation in total polyphenol contents andsignificant variations between untreated and cold plasma

Table 2 Mean values comparison of chemical and antioxidant properties of cold plasma-treated peanut (plt 005)

Plasma treatment condition DPPH () PV (mEq O2kgminus1) AV (mg KOHgminus1) TPC (mg gallic acid100 g) MC ()1 34W 16 Lmin 12min 9329plusmn 035c 230plusmn 011e 312plusmn 018a 21348plusmn 071ef 467plusmn 008cd2 34W 16 Lmin 4min 9432plusmn 021ab 253plusmn 009e 140plusmn 015bc 20073plusmn 141gh 488plusmn 003bc3 25W 10 Lmin 15min 9467plusmn 028a 233plusmn 005e 106plusmn 011c 20020plusmn 064gh 489plusmn 014bc4 25W 20 Lmin 8min 9432plusmn 007ab 240plusmn 009e 111plusmn 016c 19745plusmn 377h 520plusmn 003ab5 34W 4 lmin 4min 9441plusmn 021ab 833plusmn 051c 305plusmn 009a 22605plusmn 350de 45plusmn 0013d6 10W 10 Lmin 8min 9442plusmn 035a 233plusmn 005e 105plusmn 008c 20205plusmn 322fgh 517plusmn 008ab7 25W 10 Lmin 8min 949plusmn 007a 278plusmn 004e 110plusmn 016c 21270plusmn 417fg 519plusmn 008ab8 25W 05 Lmin 8min 9325plusmn 007c 1395plusmn 086a 316plusmn 012a 34115plusmn 212a 330plusmn 001f9 16W 4 Lmin 4min 9447plusmn 042ab 171plusmn 029e 112plusmn 017c 20224plusmn 317fgh 528plusmn 002a10 25W 10 Lmin 1min 9475plusmn 014a 159plusmn 013e 084plusmn 008c 2027plusmn 361fgh 533plusmn 004a11 16W 16 Lmin 4min 9473plusmn 021a 244plusmn 007e 105plusmn 022c 19923plusmn 141h 529plusmn 010a12 16W 16 Lmin 12min 9437plusmn 014ab 217plusmn 038e 115plusmn 005c 19411plusmn 547h 488plusmn 015bc13 40W 10 Lmin 8min 9469plusmn 007a 237plusmn 019e 153plusmn 049bc 24392plusmn 556c 440plusmn 012d14 34W 4 Lmin 12min 9359plusmn 028bc 681plusmn 069d 329plusmn 068a 30398plusmn 283b 342plusmn 011f15 16W 4 Lmin 12min 9413plusmn 007abc 1020plusmn 015b 241plusmn 060ab 23054plusmn 208d 391plusmn 001e16 Control 9472plusmn 035a 156plusmn 020e 082plusmn 022c 20023plusmn 141gh 538plusmn 010a

All values are meanplusmn SD andashhValues in the same column with different superscripts for each type of analysis are significantly different DPPH 11-diphenyl-2-picrylhydrazyl PV peroxide value AV acid value TPC total phenolic content MC moisture content


treated (plt 005) +e reported results on the effects of coldplasma treatment on the total phenolic contents of the foodproducts have a wide degree of variation A decrease in thetotal polyphenols was reported in orange juice [61] whitegrape juice [12] and lambrsquos lettuce [62] On the other handno significant effect in apples [63] but a significant increasein cashew apple juice [64] and blueberries [65] were alsoreported Recent studies using microwave plasma treatmentof mandarins increased the total phenolic content [66]

Garofulic et al [9] studied the effect of atmospheric-pressure plasma treatment on the phenolic acids of sourcherry Marasca juice the result reveal that enhanced theconcentration of phenolic acids Herceg et al [67] evaluatedthe effect of gas plasma on the phenolic content of pome-granate juice and an increase in total phenolic content wasobserved As Table 2 shows in some experiments phenoliccontent was increased UV radiations and reaction oxygenspecies formed may be responsible for the increasing phe-nolic compounds which are extracted from the upper cellsbecause phenols protect cells against the damaging effects ofexternal stress such as reactive oxygen species

+erefore the amounts of polyphenols may varydepending on the cold plasma operating conditions appliedand total polyphenols were not affected by cold plasmaunder the optimal conditions Most setups as shown inTable 2 except 34W 16 Lmin 12min 34W 4 Lmin 4min25W 05 Lmin 8min 34W 10 Lmin 8min 40W 4 Lmin 12min and 16W 4 Lmin 12min were optimumwhen compared to the control

35 Antioxidant Activity Although antioxidant activity isnot a direct quality attribute used in the food industries it isa close indicator of various polyphenols present in the foodproducts +e antioxidant effects of phenolic compoundscould be due to their redox properties which includepossible mechanisms such as free-radical scavenging ac-tivity transition metal-chelating activity and singlet-oxygenquenching capacity [68]

+ere was no significant difference (pgt 005) in anti-oxidant activity between utmost cold plasma operatingconditions as indicated in Table 2 during this research studyIn previous research no significant changes in the antiox-idant capacity after cold treatment were reported in radishsprouts kiwifruits red chicory and onion powder [69ndash72]However some studies have shown a reduction in antiox-idant activity after cold treatments in apples white grapejuice and cashew apple juice on an extended exposure[12 63 64] Almeida et al [61] reported a reduction in theantioxidant capacity of prebiotic orange juice after a directmode of plasma treatment whereas insignificant effects werereported when treated under indirect mode

36 Moisture Content Attree et al [58] reported themoisture content of raw peanut seed ranged from 5 to 6and our result was 538 as indicated in Table 2 +emoisture loss was found to be a function of the linear effectof power air flow rate and treatment time and a significant(plt 005) difference was observed (Table 2) +e causes of

loss in the moisture of the peanut are the interaction of ionselectrons and energetic species of neutral atoms and UV-Vis radiations cause a rapid removal of low molecularcontaminants such as additives processing aids andadsorbed species+emoisture content of peanut is a criticalfactor to be measured and controlled in its marketingprocessing and storage [73] Additionally it has a profoundeffect on its characteristics texture palatability consumerpreferably and preservation time and related studies in-dicated that moisture content accelerated the process ofoxidative rancidity reactions and further affected theproduct taste when the moisture is too high or too low butduring this study the moisture of the peanut was not se-verely reduced and it is near to the optimum moisturecontent of peanut for storage (515) according to [74]

According to +irumdas et al [18] plasma treatmentloss of moisture from the surface was due to etching+erefore it was observed that the moisture loss increaseswith an increase in plasma power treatment time anddecreases in air plasma rate Moisture loss depends mainlyon water loss and it is important because it affects the visualappearance and texture of the peanut and causes a reductionin saleable weight

4 Conclusion

+e applications of plasma in the food industry is still anemerging field with promising results for fast effective safeand green modification of food It was shown that the PVAV total polyphenols antioxidant activity moisture con-tent and fatty acid values were analyzed using cold plasmawhere slight changes were observed on some physical pa-rameters +e most important finding of this research wasthe observation of the strong relationship between powerplasma air flow rate and treatment time toward the effect onpeanut quality From this study it is possible to build a betterunderstanding of how the quality parameters of peanuts aresubjected to atmospheric plasma treatment conditions andcould help to obtain the optimum condition of plasmapower air flow rate and treatment time

Data Availability

+e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

+e authors declare that they have no conflicts of interest

Acknowledgments

+e authors would like to acknowledge financial supportfrom the project LO1411 (NPU I) funded by the Ministry ofEducation Youth and Sports of the Czech Republic

References

[1] Q Wang Peanut Processing Characteristics and QualityEvaluation Springer Berlin Germany 2017


[2] C Sarvamangala M V C Gowda and R K VarshneyldquoIdentification of quantitative trait loci for protein content oilcontent and oil quality for groundnut (Arachis hypogaea L)rdquoField crops research vol 122 no 1 pp 49ndash59 2011

[3] O Canavar and M A Kaynak ldquoDetermination of yield andyield components and seed quality of peanuts (Arachishypogaea L) at different harvest timesrdquo International Journalof Agronomy and Plant Production vol 4 pp 3791ndash38032013

[4] R Sandosskumar M Karthikeyan S MathiyazhaganM Mohankumar G Chandrasekar and R VelazhahanldquoInhibition of Aspergillus flavus growth and detoxification ofaflatoxin B1 by the medicinal plant zimmu (Allium sativum Ltimes Allium cepa L)rdquo World Journal of Microbiology and Bio-technology vol 23 no 7 pp 1007ndash1014 2006

[5] A Chala A Mohammed A Ayalew and H SkinnesldquoNatural occurrence of aflatoxins in groundnut (Arachishypogaea L) from eastern Ethiopiardquo Food Control vol 30no 2 pp 602ndash605 2013

[6] P Basaran N Basaran-Akgul and L Oksuz ldquoElimination ofAspergillus parasiticus from nut surface with low pressurecold plasma (LPCP) treatmentrdquo Food Microbiology vol 25no 4 pp 626ndash632 2008

[7] W A Khan M Z Khan A Khan and I Hussain ldquoPatho-logical effects of aflatoxin and their amelioration by vitamin EinWhite Leghorn layersrdquo Pakistan Veterinary Journal vol 30pp 155ndash162 2010

[8] B G Dasan MMutlu and I H Boyaci ldquoDecontamination ofAspergillus flavus and Aspergillus parasiticus spores onhazelnuts via atmospheric pressure fluidized bed plasma re-actorrdquo International Journal of Food Microbiology vol 216pp 50ndash59 2016

[9] I E Garofulic A R Jambrak S Milosevic V Dragovic-Uzelac Z Zoric and Z Herceg ldquo+e effect of gas phaseplasma treatment on the anthocyanin and phenolic acidcontent of sour cherry Marasca (Prunus cerasus var Marasca)juicerdquo LWT-Food Science and Technology vol 62 no 1pp 894ndash900 2015

[10] N N Misra S Kaur B K Tiwari A Kaur N Singh andP J Cullen ldquoAtmospheric pressure cold plasma (ACP)treatment of wheat flourrdquo Food Hydrocolloids vol 44pp 115ndash121 2015

[11] G Fridman G Friedman A Gutsol A B ShekhterV N Vasilets and A Fridman ldquoApplied plasma medicinerdquoPlasma Processes and Polymers vol 5 no 6 pp 503ndash5332008

[12] S K Pankaj Z Wan W Colonna and K M Keener ldquoEffectof high voltage atmospheric cold plasma on white grape juicequalityrdquo Journal of the Science of Food and Agriculture vol 97no 12 pp 4016ndash4021 2017

[13] N N Misra B K Tiwari K S M S Raghavarao andP J Cullen ldquoNonthermal plasma inactivation of food-bornepathogensrdquo Food Engineering Reviews vol 3 no 3-4pp 159ndash170 2011

[14] O Schluter J Ehlbeck C Hertel et al ldquoOpinion on the use ofplasma processes for treatment of foodslowastrdquo Molecular Nu-trition and Food Research vol 57 no 5 pp 920ndash927 2013

[15] N Misra O Schluter and P J Cullen Cold Plasma in Foodand Agriculture Fundamentals and Applications AcademicPress Cambridge MA USA 2016

[16] H Miao and G Yun ldquo+e sterilization of Escherichia coli bydielectric-barrier discharge plasma at atmospheric pressurerdquoApplied Surface Science vol 257 no 16 pp 7065ndash7070 2011

[17] J Pinela and I C F R Ferreira ldquoNonthermal physicaltechnologies to decontaminate and extend the shelf-life offruits and vegetables trends aiming at quality and safetyrdquoCritical Reviews in Food Science and Nutrition vol 57 no 10pp 2095ndash2111 2015

[18] R+irumdas R R Deshmukh and U S Annapure ldquoEffect oflow temperature plasma processing on physicochemicalproperties and cooking quality of basmati ricerdquo InnovativeFood Science and Emerging Technologies vol 31 pp 83ndash902015

[19] P Basaran and U Akhan ldquoMicrowave irradiation of hazel-nuts for the control of aflatoxin producing Aspergillus par-asiticusrdquo Innovative Food Science and Emerging Technologiesvol 11 pp 113ndash117 2010

[20] C Hertwig A Leslie N Meneses K Reineke C Rauh andO Schluter ldquoInactivation of Salmonella Enteritidis PT30 onthe surface of unpeeled almonds by cold plasmardquo InnovativeFood Science and Emerging Technologies vol 44 pp 242ndash2482017

[21] M Korachi F Ozen N Aslan et al ldquoBiochemical changesto milk following treatment by a novel cold atmosphericplasma systemrdquo International Dairy Journal vol 42pp 64ndash69 2015

[22] U Schnabel R Niquet O Schluter H Gniffke andJ Ehlbeck ldquoDecontamination and sensory properties ofmicrobiologically contaminated fresh fruits and vegetables bymicrowave plasma processed air (PPA)rdquo Journal of FoodProcessing and Preservation vol 39 no 6 pp 653ndash662 2014

[23] B Kim H Yun S Jung et al ldquoEffect of atmospheric pressureplasma on inactivation of pathogens inoculated onto baconusing two different gas compositionsrdquo Food Microbiologyvol 28 no 1 pp 9ndash13 2011

[24] H-J Kim H I Yong S Park W Choe and C Jo ldquoEffects ofdielectric barrier discharge plasma on pathogen inactivationand the physicochemical and sensory characteristics of porkloinrdquo Current Applied Physics vol 13 no 7 pp 1420ndash14252013

[25] J-S Kim E-J Lee E H Choi and Y-J Kim ldquoInactivation ofStaphylococcus aureus on the beef jerky by radio-frequencyatmospheric pressure plasma discharge treatmentrdquo In-novative Food Science and Emerging Technologies vol 22pp 124ndash130 2014

[26] C Hertwig K Reineke J Ehlbeck B Erdogdu C Rauh andO Schluter ldquoImpact of remote plasma treatment on naturalmicrobial load and quality parameters of selected herbs andspicesrdquo Journal of Food Engineering vol 167 pp 12ndash17 2015

[27] C Hertwig K Reineke J Ehlbeck D Knorr and O SchluterldquoDecontamination of whole black pepper using different coldatmospheric pressure plasma applicationsrdquo Food Controlvol 55 pp 221ndash229 2015

[28] T Homola R Krumpolec M Zemanek et al ldquoAn array ofmicro-hollow surface dielectric barrier discharges for large-area atmospheric-pressure surface treatmentsrdquo PlasmaChemistry and Plasma Processing vol 37 no 4 pp 1149ndash1163 2017

[29] S K Bishi K Lokesh M K Mahatma N KhatediyaS M Chauhan and J B Misra ldquoQuality traits of Indianpeanut cultivars and their utility as nutritional and functionalfoodrdquo Food Chemistry vol 167 pp 107ndash114 2015

[30] V L Singleton and J A Rossi ldquoColorimetry of total phenolicswith phosphomolybdic-phosphotungstic acid reagentsrdquoAmerican journal of Enology and Viticulture vol 16 no 3pp 144ndash158 1965


[31] M M Win A Abdul-Hamid B S Baharin F AnwarM C Sabu and M S Pak-Dek ldquoPhenolic compounds andantioxidant activity of peanutrsquos skin hull raw kernel androasted kernel flourrdquo Pakistan Journal of Botany vol 43pp 1635ndash1642 2011

[32] J Young T Whitaker P Blankenship et al ldquoEffect of ovendrying time on peanut moisture determinationrdquo Transactionsof the ASAE vol 25 pp 491ndash495 1982

[33] S-S Li R-Y Yuan L-G Chen et al ldquoSystematic qualitativeand quantitative assessment of fatty acids in the seeds of 60tree peony (Paeonia section Moutan DC) cultivars by GC-MSrdquo Food Chemistry vol 173 pp 133ndash140 2015

[34] F Jubeen I A Bhatti U Maqbool and S Mehboob ldquoFungalincidence aflatoxin B 1 tocopherols and fatty acids dynamicsin ground and tree nuts during storage at twomoisture levelsrdquoInternational Journal of Agriculture and Biology vol 14 2012

[35] E-C Shin B D Craft R B Pegg R D Phillips andR R Eitenmiller ldquoChemometric approach to fatty acidprofiles in Runner-type peanut cultivars by principal com-ponent analysis (PCA)rdquo Food Chemistry vol 119 no 3pp 1262ndash1270 2010

[36] I Albertos A B Martın-Diana P J Cullen et al ldquoEffects ofdielectric barrier discharge (DBD) generated plasma on mi-crobial reduction and quality parameters of fresh mackerel(Scomber scombrus) filletsrdquo Innovative Food Science andEmerging Technologies vol 44 pp 117ndash122 2017

[37] X V Yepez and K M Keener ldquoHigh-voltage atmosphericcold plasma (HVACP) hydrogenation of soybean oil withouttrans-fatty acidsrdquo Innovative Food Science and EmergingTechnologies vol 38 pp 169ndash174 2016

[38] B Cammerer and L W Kroh ldquoShelf life of linseeds andpeanuts in relation to roastingrdquo LWT-Food Science andTechnology vol 42 no 2 pp 545ndash549 2009

[39] C Sarangapani D Ryan Keogh J Dunne P Bourke andP J Cullen ldquoCharacterisation of cold plasma treated beef anddairy lipids using spectroscopic and chromatographicmethodsrdquo Food Chemistry vol 235 pp 324ndash333 2017

[40] S F Mexis and M G Kontominas ldquoEffect of c-irradiation onthe physicochemical and sensory properties of cashew nuts(Anacardium occidentale L)rdquo LWT-Food Science and Tech-nology vol 42 no 9 pp 1501ndash1507 2009

[41] P Zoumpoulakis V J Sinanoglou A Batrinou I F StratiS Miniadis-Meimaroglou and K Sflomos ldquoA combinedmethodology to detect c-irradiated white sesame seeds andevaluate the effects on fat content physicochemical propertiesand protein allergenicityrdquo Food Chemistry vol 131 no 2pp 713ndash721 2012

[42] M Arici F A Colak and U Gecgel ldquoEffect of gamma ra-diation on microbiological and oil properties of black cumin(Nigella sativa L)rdquo Grasas y Aceites vol 58 no 4 pp 339ndash343 2007

[43] V Nepote M G Mestrallet and N R Grosso ldquoOxidativestability in fried-salted peanuts elaborated with high-oleic andregular peanuts from Argentinardquo International Journal ofFood Science and Technology vol 41 no 8 pp 900ndash909 2006

[44] R Olmedo V Nepote M G Mestrallet and N R GrossoldquoEffect of the essential oil addition on the oxidative stability offried-salted peanutsrdquo International Journal of Food Scienceand Technology vol 43 no 11 pp 1935ndash1944 2008

[45] C Alimentarius Codex Alimentarius Standards for Fats andOils from Vegetable Sources Section 2 Codex AlimentariusRome Italy 1999

[46] M Al-Bachir ldquoEffect of gamma irradiation on fungal loadchemical and sensory characteristics of walnuts (Juglans regia

L)rdquo Journal of Stored Products Research vol 40 no 4pp 355ndash362 2004

[47] H-J Kim H I Yong S Park K Kim W Choe and C JoldquoMicrobial safety and quality attributes of milk followingtreatment with atmospheric pressure encapsulated dielectricbarrier discharge plasmardquo Food Control vol 47 pp 451ndash4562015

[48] D Ladikos and V Lougovois ldquoLipid oxidation in musclefoods a reviewrdquo Food Chemistry vol 35 no 4 pp 295ndash3141990

[49] Y Rao B Xiang X Zhou Z Wang S Xie and J XuldquoQuantitative and qualitative determination of acid value ofpeanut oil using near-infrared spectrometryrdquo Journal of FoodEngineering vol 93 no 2 pp 249ndash252 2009

[50] S Choi P Puligundla and C Mok ldquoCorona discharge plasmajet for inactivation of Escherichia coli O157H7 and Listeriamonocytogenes on inoculated pork and its impact on meatquality attributesrdquo Annals of Microbiology vol 66 no 2pp 685ndash694 2015

[51] N Ulbin-Figlewicz and A Jarmoluk ldquoEffect of low-pressureplasma treatment on the color and oxidative stability of rawpork during refrigerated storagerdquo Food Science and Tech-nology International vol 22 no 4 pp 313ndash324 2015

[52] D D Jayasena H J Kim H I Yong et al ldquoFlexible thin-layerdielectric barrier discharge plasma treatment of pork butt andbeef loin effects on pathogen inactivation and meat-qualityattributesrdquo Food Microbiology vol 46 pp 51ndash57 2015

[53] S G Joshi M Cooper A Yost et al ldquoNonthermal dielectric-barrier discharge plasma-induced inactivation involves oxi-dative DNA damage and membrane lipid peroxidation inE-scherichia colirdquo Antimicrobial Agents and Chemotherapyvol 55 no 3 pp 1053ndash1062 2011

[54] J Van Durme A Nikiforov J Vandamme C Leys andA DeWinne ldquoAccelerated lipid oxidation using non-thermalplasma technology evaluation of volatile compoundsrdquo FoodResearch International vol 62 pp 868ndash876 2014

[55] R +irumdas C Sarangapani and U S Annapure ldquoColdplasma a novel non-thermal technology for food processingrdquoFood Biophysics vol 10 no 1 pp 1ndash11 2014

[56] Y Shem-Tov H Badani A Segev I Hedvat S Galili andR Hovav ldquoDetermination of total polyphenol flavonoid andanthocyanin contents and antioxidant capacities of skins frompeanut (Arachis hypogaea) lines with different skin colorsrdquoJournal of Food Biochemistry vol 36 no 3 pp 301ndash308 2012

[57] Y Chukwumah L Walker and M Verghese ldquoPeanut skincolor a biomarker for total polyphenolic content andantioxidative capacities of peanut cultivarsrdquo InternationalJournal of Molecular Sciences vol 10 no 11 pp 4941ndash49522009

[58] R Attree B Du and B Xu ldquoDistribution of phenoliccompounds in seed coat and cotyledon and their contribu-tion to antioxidant capacities of red and black seed coatpeanuts (Arachis hypogaea L)rdquo Industrial Crops and Prod-ucts vol 67 pp 448ndash456 2015

[59] M Kornsteiner K-H Wagner and I Elmadfa ldquoTocopherolsand total phenolics in 10 different nut typesrdquo Food Chemistryvol 98 no 2 pp 381ndash387 2006

[60] J Yang R H Liu and L Halim ldquoAntioxidant and anti-proliferative activities of common edible nut seedsrdquo LWT-Food Science and Technology vol 42 no 1 pp 1ndash8 2009

[61] F D L Almeida R S Cavalcante P J Cullen et al ldquoEffects ofatmospheric cold plasma and ozone on prebiotic orangejuicerdquo Innovative Food Science and Emerging Technologiesvol 32 pp 127ndash135 2015


[62] F Grzegorzewski J Ehlbeck O Schluter L W Kroh andS Rohn ldquoTreating lambrsquos lettuce with a cold plasma-Influenceof atmospheric pressure Ar plasma immanent species on thephenolic profile of Valerianella locustardquo LWT-Food Scienceand Technology vol 44 no 10 pp 2285ndash2289 2011

[63] I Ramazzina S Tappi P Rocculi et al ldquoEffect of cold plasmatreatment on the functional properties of fresh-cut applesrdquoJournal of Agricultural and Food Chemistry vol 64 no 42pp 8010ndash8018 2016

[64] O Rodrıguez W F Gomes S Rodrigues andF A N Fernandes ldquoEffect of indirect cold plasma treatmenton cashew apple juice (Anacardium occidentale L)rdquo LWTvol 84 pp 457ndash463 2017

[65] C Sarangapani G OrsquoToole P J Cullen and P BourkeldquoAtmospheric cold plasma dissipation efficiency of agro-chemicals on blueberriesrdquo Innovative Food Science andEmerging Technologies vol 44 pp 235ndash241 2017

[66] M Y Won S J Lee and S C Min ldquoMandarin preservationby microwave-powered cold plasma treatmentrdquo InnovativeFood Science amp Emerging Technologies vol 39 pp 25ndash322017

[67] Z Herceg D B Kovacevic J G Kljusuric A R JambrakZ Zoric and V Dragovic-Uzelac ldquoGas phase plasma impacton phenolic compounds in pomegranate juicerdquo FoodChemistry vol 190 pp 665ndash672 2016

[68] B Shan Y Z Cai M Sun and H Corke ldquoAntioxidant ca-pacity of 26 spice extracts and characterization of theirphenolic constituentsrdquo Journal of Agricultural and FoodChemistry vol 53 no 20 pp 7749ndash7759 2005

[69] Y J Oh A Y Song and S C Min ldquoInhibition of Salmonellatyphimurium on radish sprouts using nitrogen-cold plasmardquoInternational Journal of foodMicrobiology vol 249 pp 66ndash712017

[70] I Ramazzina A Berardinelli F Rizzi et al ldquoEffect of coldplasma treatment on physico-chemical parameters and an-tioxidant activity of minimally processed kiwifruitrdquo Post-harvest Biology and Technology vol 107 pp 55ndash65 2015

[71] F Pasquali A C Stratakos A Koidis et al ldquoAtmosphericcold plasma process for vegetable leaf decontamination afeasibility study on radicchio (red chicory Cichorium intybusL)rdquo Food Control vol 60 pp 552ndash559 2016

[72] J E Kim Y J Oh M Y Won K-S Lee and S C MinldquoMicrobial decontamination of onion powder usingmicrowave-powered cold plasma treatmentsrdquo Food Micro-biology vol 62 pp 112ndash123 2017

[73] C V Kandala and J Sundaram ldquoNondestructive moisturecontent determination of three different market type in-shellpeanuts using near infrared reflectance spectroscopyrdquo Journalof Food Measurement and Characterization vol 8 no 2pp 132ndash141 2014

[74] X-x Shen B-s Li Z Ruan P-r Zhuang and C-r ChenldquoEffects of water content on the quality of peanuts duringstoragerdquo Modern Food Science and Technology vol 5 2011


Hindawiwwwhindawicom

International Journal of

Volume 2018

Zoology

Hindawiwwwhindawicom Volume 2018

Anatomy Research International

PeptidesInternational Journal of



Journal of Parasitology Research

GenomicsInternational Journal of


Hindawi Publishing Corporation httpwwwhindawicom Volume 2013Hindawiwwwhindawicom

The Scientific World Journal

Volume 2018


BioinformaticsAdvances in

Marine BiologyJournal of



Neuroscience Journal


BioMed Research International

Cell BiologyInternational Journal of



Biochemistry Research International

ArchaeaHindawiwwwhindawicom Volume 2018


Genetics Research International


Advances in

Virolog y Stem Cells International



Enzyme Research



MicrobiologyHindawiwwwhindawicom

Nucleic AcidsJournal of

Volume 2018

Submit your manuscripts atwwwhindawicom

generated using any kind of energy which can ionize thegases such as electrical thermal optical and radioactive andX-ray electromagnetic radiation However electric orelectromagnetic fields are widely used for cold plasmageneration [12] Plasma can be generated at low or highpressure but plasma generated at atmospheric pressure is ofinterest to the food industry because it does not requireextreme process conditions [13] Cold Plasma is also knownas nonequilibrium plasma because of its low gas temper-ature of lt70degC because the applied energy leads to an elasticcollision of the gas particles atoms and electrons +e gasparticles are less energetic than the electrons in the dischargewhere the heavy particles have kinetic temperatures close toambient because the transfer of kinetic energy to otherparticles in such a way that the cooling of the unchargedparticles and neutral ions is more rapid than the energytransfer from the electrons [11 14 15]

Cold plasma is a better alternative to other existingsurface decontamination methods due to operation at at-mospheric pressure low-temperature long operative du-ration and economical and simple systems [16] and it is anovel and green food preservation technology and has onlybeen applied at very small scales [17] +is technology isgradually finding acceptance among food researchers for thesurface sterilization but the effect of cold plasma on thesensitive constituents of foods mainly lipids vitamins andbioactive compounds and the physical quality of theproduct being treated not addressed [13]

Atmospheric cold plasma surface treatment processoffers novel food preservation properties and has been testedwith different plasma setup and gas sources in differentcereal grains [8 18] peanuts [6 8 19 20] dairy [21] fruitsand vegetables [22] meat [23ndash25] and spices [26 27] butnone of them have investigated the synergetic effect of coldplasma operating conditions (plasma power air flow rateand treatment time) on the quality of the treated foodproduct

Numerous researches have been done to investigate theeffects of plasma on food constituents and various chemicalreactions are induced by plasma but there has been spec-ulation on the free radical formation when fatty foods andwith high antioxidant and polyphenol compounds are ex-posed to plasma energy Cold plasma can generate reactiveand free radical species and these species that have strongoxidation capacities Treating high lipid-containing mate-rials with cold plasma could lead to lipid and consequently todevelopment of off-flavor and off-odor and in loss of naturalantioxidants and caused the formation of many volatilesrelated to lipid oxidation [24] Peanut contains the highpercentage of mono- and polyunsaturated fatty acids and thelow percentage of saturated fatty acids [1]

Little information is available about the synergistic in-fluence of cold plasma operation conditions (plasma powerair flow rate and treatment time) peroxide value acid valuefatty acid profile antioxidant activity total polyphenols andmoisture contents of peanuts +erefore the current ob-jective was to study the influence of multihollow surfacedielectric barrier discharge plasma operating conditions onchemical and antioxidant properties of peanut

2 Experimental Details

21 Chemicals and Samples n-Hexane methanol 95ethanol potassium hydroxide sodium thiosulphate po-tassium iodide chloroform glacial acetic acid 22-diphenyl-1-picryhydrzyl radical (DPPH) FolinndashCiocalteu sodiumcarbonate starch and gallic acid A domestic commercialpeanut (Roba variety) was obtained from the Were ResearchCenter Oromia Ethiopia

22 Plasma Treatment of Peanuts Plasma surface modifi-cation of peanuts was carried out using a special reactor forplasma treatment of small peanut samples +e rector wasbased on commercial coplanar-type multihollow surfacedielectric barrier discharge unit for which the detail char-acteristics and properties were reported by [28] A schematicdraw of the experimental setup is shown in Figure 1Multihollow surface dielectric barrier discharge plasma(MSDBD) is composed of two planar metal electrodes atdistance 05mm both embedded in alumina ceramic +eentire surface is perforated by creating the18times189mm(sim34 cm2) Multihollow surface DBD plasma was generatedby a sinusoidal alternate current (sim27 kHz) high-voltage(10 kV) power source An MSDBD unit was embedded in afeed chamber enabling the plasma generation at a certainflow of plasma forming gas

Plasma treatment of peanuts was done at varied treat-ment conditions Total input power monitored by a com-mercial wattmeter was 10ndash40W +e flow rate of ambientair with humidity 20ndash30 was controlled by the thermalmass flow controller RED-Y in the range (05ndash20 Lmin)+e treatment time was varied from 1ndash15min based onrotatable central composite design IR thermometer FLUKE62 MAX 3M DROP waterdust resistance IP54 with thetemperature range minus30 to 500degC was used to measure thetemperature of the ceramic during the experiment Sixpeanuts were treated by plasma in one batch +e peanutswere mechanically moved and turned around by inert plasticrod during the plasma treatment to provide a homogeneoussurface treatment of peanuts +e samples were taken fromthe plasma field after treatment and the treated peanutswere cooled to room temperature packed in polyethylenebags and kept at 4degC for further analysis

23 Sample Preparation for Extraction +e cold plasma-treated and the untreated peanut seeds were milled(High-Speed Universal Disintegrator (FW100) GrinderChina) with a speed of rotating knife (2400 rpm) and passedthrough a mesh size 16 sieve to obtain identically sizedparticles and then was retained in a sealed bag in a re-frigerator (1-2degC) until use Milled peanut seed particle size isimportant to facilitate analyses of mass transfer during theextraction of oil and antioxidant

24 Extraction Methods +e extraction was performed induplicate with solvent n-hexane (99 purity) An au-tomated Soxhlet set (+e Soxhlet extractor SXT-06







TPC C times VM

(1)



Plasma

PeanutFence

HV

Ambientair flow

Holes

Electrodes





Aolowast 100 (2)













002040608

112


Abso

rban

ce at

760

nm

y = 0004x + 00917R2 = 09984










80

60

40

20

0

Tem

pera

ture

of t

he ce

ram

ic (deg

C)

P1 P2 P3 P4 P5 P7P6 P8 P9 P10

P11

P12

P13

P14

P15


Heating map1

3

5

7

9

11

13

15

Plas

ma o

pera

ting

cond

ition

s70

60

50

40

30

Cer

amic

tem

pera

ture

(degC)

303828306426347033292831476229























4 Conclusion


Data Availability




Acknowledgments


References


















































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018







TPC C times VM

(1)



Plasma

PeanutFence

HV

Ambientair flow

Holes

Electrodes





Aolowast 100 (2)













002040608

112


Abso

rban

ce at

760

nm

y = 0004x + 00917R2 = 09984










80

60

40

20

0

Tem

pera

ture

of t

he ce

ram

ic (deg

C)

P1 P2 P3 P4 P5 P7P6 P8 P9 P10

P11

P12

P13

P14

P15


Heating map1

3

5

7

9

11

13

15

Plas

ma o

pera

ting

cond

ition

s70

60

50

40

30

Cer

amic

tem

pera

ture

(degC)

303828306426347033292831476229























4 Conclusion


Data Availability




Acknowledgments


References


















































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018




Aolowast 100 (2)













002040608

112


Abso

rban

ce at

760

nm

y = 0004x + 00917R2 = 09984










80

60

40

20

0

Tem

pera

ture

of t

he ce

ram

ic (deg

C)

P1 P2 P3 P4 P5 P7P6 P8 P9 P10

P11

P12

P13

P14

P15


Heating map1

3

5

7

9

11

13

15

Plas

ma o

pera

ting

cond

ition

s70

60

50

40

30

Cer

amic

tem

pera

ture

(degC)

303828306426347033292831476229























4 Conclusion


Data Availability




Acknowledgments


References


















































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018









80

60

40

20

0

Tem

pera

ture

of t

he ce

ram

ic (deg

C)

P1 P2 P3 P4 P5 P7P6 P8 P9 P10

P11

P12

P13

P14

P15


Heating map1

3

5

7

9

11

13

15

Plas

ma o

pera

ting

cond

ition

s70

60

50

40

30

Cer

amic

tem

pera

ture

(degC)

303828306426347033292831476229























4 Conclusion


Data Availability




Acknowledgments


References


















































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018






















4 Conclusion


Data Availability




Acknowledgments


References


















































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018

















































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018


research article - hindawi publishing...

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