THE EFFECTS OF POSTHARVEST TREATMENTS OF SALICYLIC ACID AND POTASSIUM PERMANGANATE ON THE STORAGE OF KIWIFRUIT

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1 76 Bulgrin Journl of Agriculturl Science, 6 (No ), 76-8 Agriculturl Acdemy THE EFFECTS OF POSTHARVEST TREATMENTS OF SALICYLIC ACID AND POTASSIUM PERMANGANATE ON THE STORAGE OF KIWIFRUIT E. BAL * nd S. CELIK Deprtment of Horticulture, Agriculturl Fculty, Nmik Keml University, Tekirdg, Turkey Astrct BAL, E. nd S. CELIK,. The effects of posthrvest tretments of slicylic cid nd potssium permngnte on the storge of kiwifruit. Bulg. J. Agric. Sci., 6: 76-8 Kiwifruit (Actinidi delicios cv. Hywrd) ws used to investigte the effects of slicylic cid (. mm, mm) nd potssium permngnte tretments on fruit qulity nd storge life during storge for two yers. After tretments, kiwifruits were stored in MAP t C with 8-9% RH for dys. At certin intervls, smples were collected from ech tretment for physicl nd chemicl nlysis (e.g. flesh firmness, totl solule solids, titrtle cid, totl chlorophyll content, scoric cid content, reduction sugr content nd degusttion test). Slicylic cid tretment hs een found to dely the ripening of kiwifruits. In slicylic cid nd slicylic cid with potssium permngnte treted fruits, fruit softening, titrtle cids, totl chlorophyll concentrtion, scoric cid content decresed nd totl solule solid, reducing sugr content nd degusttion test score incresed slowly thn control fruits during storge. Control fruits decresed fster thn other tretments. At end of the dys in oth yers, in these tretments were lso found moderte (mrketle) in tste ssessment. Key words: Kiwifruit, slicylic cid, potssium permngnte, fruit qulity Introduction Kiwifruit, climcteric fruit, is commonly stored for long periods t low tempertures. During cold storge, the min fctor limiting storge is fruit softening nd wter loss (Beever nd Hopkirk, 99; Pekmezci et l., ). An extreme cse is kiwifruit in which even very low ethylene concentrtion induces flesh softening, limiting long-term cold storge (Crisosto et l., ). Fruit softenning nd ripenning cn e enhnced with different pplictions or my e locked. Removl of ethylene from storge rooms is very importnt for climcteric fruits. Modified tmosphere pckging plus use of ethylene sorent is useful E-mil: el@nku.edu.tr technique for mintining posthrvest qulity. In common commercil use to remove ethylene from the tmosphere is to sor nd oxidize it with potssium permngnte (KMnO ). Severl studies hve shown tht KMnO pplictions dely fruit softening nd increse posthrvest life (Illeperum nd Jysuriy, ; Cstro et l., ; Corre et l., ). Slicylic cid (SA) is plnt hormone inhiiting ethylene iosynthesis nd delying the senescence (Ozeker, ). SA hs een shown to inhiit the conversion of ACC into ethylene (Leslie nd Romni, 988) y suppressing ACC oxidse ctivity (Fn et l., 996). SA is lso involved in locl nd systemic resistnce to pthogens (Ylpni et l., 99; Kng

2 The Effects of Posthrvest Tretments of Slicylic Acid nd Potssium Permngnte on the Storge of Kiwifruit 77 et l., ). Exogenous supplied SA hs een reported to dely the ripening of pple (Yn et l., 998), pech (Hn et l., ), persimmon (Li nd Hn, ), nn (Srivstv nd Dwivedi, ). Both SA nd its derivtive cetylslicylic cid (ASA) hve een shown to inhiit ethylene production in cultured per cells (Leslie nd Romni, 988) nd crrot cell suspension cultures (Roustn et l., 99). Zinuri et l. () ttriuted the effects of SA to inhiition of mngo skin ripening. This work ws conducted to exmine the effect of SA nd KMnO tretments on cold storge period nd physico-chemicl chnges in kiwifruits. Mteril nd Methods Plnt mteril Hywrd kiwifruit the first yer (7..6) on verge 6.% totl solule solids nd fruit firmness verge 7. kg, the second yer (..7) on verge 6.% totl solule solids nd fruit firmness ws reched verge 7.8 kg were hrvested in Tekirdg, Turkey. Kiwifruits uniform in shpe nd size nd free of fungl infection were selected. Tretments nd storge Kiwifruits were sujected to the following tretments: Group. Control Group. Potssium permngnte schet (KMnO ) Group.. mm slicylic cid Group. mm slicylic cid Group.. mm slicylic cid + KMnO schet Group 6. mm slicylic cid + KMnO schet Appliction of slicylic cid SA ws pplied y immersing fruit for min in solution of. mm nd mm SA. After immersion, the fruit were dried. Appliction of potssium permngnte This ppliction nd the nturl cly were otined from mixture of potssium permngnte grnules used BI-ON is trdemrk. High gs permeility gs (schets) emedded nd pckged with 9 grms of KMnO (verge 9 g/kg) of grnules were plced into one of the pckges. After tretments, 8 kiwifruits were put in polyethylene continer nd pcked with polyethylene gs (LDPE-low density polyethylene, μ thicknesses) nd stored t C nd 8-9% reltive humidity for dys. Qulity evlution Physicl nd chemicl qulity fctors were mesured periodiclly fter tretment nd every dy. Kiwifruit firmness ws determined y penetrometer with tip rdius of 8 mm nd expressed s kg unit. Percentge of totl solule solid (TSS) content ws determined with hnd refrctometer. Titrtle cids (TA) ws determined y titrtion with. N NOH nd expressed s mg/ ml citric cid. Totl chlorophyll content ws nlyzed ccording to Arnon (99). Ascoric cid mesurement ws mde following the indophenol dye titrtion method (Cemeroglu, 7). Reducing sugr content ws determined ccording to Rose (99). Degusttion test ws evluted y pnelist using point scle (: very d, : d, : moderte, mrketle, : good, : very good). Sttisticl nlysis The dt for the experiment ws nlyzed s completely rndomized locks design with three replictes nd ech replicte consisted of pckges. An nlysis of vrince ws used to nlyze difference etween mens nd the LSD test ws pplied for men seprtion t P.. All nlyses were done y mens of MSTAT-C sttisticl softwre. Results Fruit firmness The fruit firmness of the kiwifruits continuously decresed during storge. Fruits of ll tretments hd gret decrese in firmness especilly in th dy nd slower therefter (Figure ). Control fruits firmness decresed fster thn other tretments nd softened

3 78 E. Bl nd S. Celik th dy 8 th dy th dy 6 th dy th dy,, Fruit firmness (kg),,,, Fruit firmness (kg),,,, Fig.. Fruit firmness of kiwifruit treted KMnO nd SA during storge in the first yer ()(initil: 7.6 kg) nd second yer ()(initil :7. kg) of the experiment. Verticl rs represent ± SE excessively t the end of storge period. In first nd second yer of the experiment KMnO treted kiwifruit mintined firmness thn non-kmno treted. At the end of th dy, SA +K nd SA.+K tretments were firmer in oth yers. Totl solule solids In ll tretments, totl solule solids incresed during storge. The increse of solule solids ws more pronounced until 6 th dy nd fter tht period it ws lmost stle in oth yers (Figure ). First yer, t the end of th dy, while the highest TSS content of kiwifruits ws detected in SA. tretments, the lowest TSS content ws determined in KMnO nd in SA.+ K tretments. At the end of th dy of second yer, TSS content of kiwifruits in control showed highest vlues nd the lowest TSS content ws detected for SA +K tretment. Titrtle cids Titrtle cidity of kiwifruit t hrvest ws determined.6 mg/ ml for the first yer nd.6 mg/ ml for the second yer. Then TA in kiwifruits decresed with storge durtion s presented in Figure. After th dy of storge, TA content ws lower in controls thn other treted fruits in oth yers. First yer, the highest vlues of TA detected in fruit treted with SA +K nd SA.+K in th dy, the second th dy 8 th dy th dy 6 th dy th dy Totl solule solids (%) Totl solule solids (%) Fig.. Totl solule solids of kiwifruit treted KMnO nd SA during storge in the first yer () (initil: %6.) nd second yer () (initil: %6.7) of the experiment. Verticl rs represent ± SE

4 The Effects of Posthrvest Tretments of Slicylic Acid nd Potssium Permngnte on the Storge of Kiwifruit 79 th dy 8 th dy th dy 6 th dy th dy Titrtle cids (mg/ ml),7,6,,,,, Titrtle cids (mg/ ml ),7,6,,,,, yer the highest vlues of TA determined in fruit treted with SA +K. Fig.. Titrtle cids content of kiwifruit treted KMnO nd SA during storge in the first yer () (initil:.6 mg/ ml) nd second yer ( )(initil:.6 mg/ ml) of the experiment. Verticl rs represent ± SE th dy 8 th dy th dy 6 th dy th dy Totl Chlorophyll The totl chlorophyll concentrtions vried etween tretments in oth yers nd ccording to the hrvest vlues generlly decresed with storge durtion (Figure ). However, in oth yers irregulr chnges were detected etween pplictions. First yer, fter th dy storge period the highest vlues of totl chlorophyll detected in fruit treted with SA +K nd lowest vlue detected in SA tretment followed y control. Second yer, fter th dy storge period the highest vlues of totl chlorophyll determined in SA tretment nd lowest vlue determined in control fruits. Ascoric Acid The scoric cid content in kiwifruit incresed initilly with the dvncement of storge period nd declined therefter s presented in Figure. During the storge period in first yer, the highest scoric cid content of kiwifruits ws detected in SA in 8 th dy nd control tretment hd the lowest scoric cid content in th dy. In the second yer of study, Totl chlorophyll (mg/g),8,7,6,,,,, Totl chlorophyll (mg/g),8,7,6,,,,, Fig.. Totl chlorophyll content of kiwifruit treted KMnO nd SA during storge in the first yer () (initil:.8 mg/g) nd second yer () (initil:.6 mg/g) of the experiment. Verticl rs represent ± SE

5 8 E. Bl nd S. Celik th dy 8 th dy th dy 6 th dy th dy Vitmin C (mg/g) the highest vlues of scoric cid determined in fruit treted with KMnO in 8 th nd scoric cid content of kiwifruits in control showed lowest vlues in th dy. At the end of the storge period, SA+K tretment for first yer nd SA tretment for second yer hd the highest scoric cid content. Vitmin C (mg/g) 6 6 Fig.. Vitmin C content of kiwifruit treted KMnO nd SA during storge in the first yer () (initil:.8 mg/g) nd second yer () (initil:. mg/g) of the experiment. Verticl rs represent ± SE Reducing sugrs In the study, t the eginning of storge, reducing sugr of kiwifruits ws round %.-%.. With kiwifruit mturity, incresing reducing sugr chnged depending on storge period nd tretments. First yer, while the highest reducing sugr content of kiwifruits ws detected in SA tretments in th dy, second yer the highest reducing sugr content of kiwifruits ws detected in SA. tretments in 6 th dy (Figure 6). In oth yers, fter dys of storge period, the lowest reducing sugr ws otined t control fruits. Degusttion test In the present study, with mturity in tste ssessment ws determined to increse the test points. Towrds the end of the storge period, excessive mturity of fruit ws determined to reduce the tste scores. First yer; while SA+K tretment in 6 th dy hd Reducing sugrs (mg/g th dy 8 th dy th dy 6 th dy th dy Reducing sgrs (mg/g Fig. 6. Reducing sugrs content of kiwifruit treted KMnO nd SA during storge in the first yer () (initil:.8 mg/g) nd second yer ()(initil:. mg/g) of the experiment. Verticl rs represent ± SE

6 The Effects of Posthrvest Tretments of Slicylic Acid nd Potssium Permngnte on the Storge of Kiwifruit 8 th dy 8 th dy th dy 6 th dy th dy Degusttion test (- point),,,,, Degusttion test (- point),,,,, Fig. 7. Degusttion test of kiwifruit treted KMnO nd SA during storge in the first () (initil: ) nd second yer () (initil: ) of the experiment. Verticl rs represent ± SE the highest degusttion test point, second yer the highest degusttion test point ws determined t SA. tretments in 6 th dy (Figure 7). First yer in th dy, control fruits were found less thn point which ws represented moderte (mrketle), in cse second yer, control nd KMnO tretments were found less thn point. Other tretments were plced ove three points in th dy. Discussion The results showed tht during storge, in treted SA nd SA with KMnO fruits, fruit firmness, TA, totl chlorophyll concentrtion, scoric cid content decresed nd TSS, reducing sugr concentrtion nd degusttion test score incresed slowly thn control fruits. In the present study, control kiwifruit rpidly softened when stored t low temperture, s evidenced y rpid decrese in fruit firmness within the first dys. This result ws in greement with the previous reports (Arpi et l., 987; Beever nd Hopkirk, 99; Kyns et l., 999; Oz, 6).Pckges of fruit with ethylene sorent schet retined the more firmness thn other tretments. In previous studies, Cstro et l. () in mngo, Kim (997) in pples, Corre et l. () in ppy fruit reported tht KMnO tretment hs slowed fruit to soften. In treted SA with KMnO fruits firmer in oth yers. Hn et l. () nd Li nd Hn () found tht immersions of persimmon in low concentrtions of SA, compred to control fruits, delyed the decline of firmness of stored fruits. In oth yers treted nd non-treted kiwifruits showed similr ehvior. The results indicted tht effect of tretments on TSS ws not regulr. The TSS incresed mostly in 6 dy storge, nd remined lmost constnt therefter for ll tretments in oth yers. In reserch, flvor cceptility of kiwifruit ws found to increse with incresing TSS. Mitchell et l. (99) identified consumers preferring sweeter (TSS > %) fruit rther thn less sweet fruit (TSS < %). At the end of the storge, lthough TSS vlue of unmrketle fruits were found round -6%, hd elow point (mrketle) on degusttion test. These findings re corroorted y Rossiter et l. (). According to these results, it my e misleding to determine simply TSS vlue for consumption eligiility. In generl, it is known tht there is reduction in citric cid content of kiwifruit during the storge period (Mrsh et l., ). In study, TA content of kiwifruits exhiited reduction dependence on ripening nd tretments towrds the end of storge period. These results re similr to those of Kyns et l. (999) nd Nmdr nd Ozcn (6). Especilly, SA with KMnO tretments ws more effective to mintin TA thn control. Similr oservtions were reported with SA treted grpes (Bl nd Kok, 7) nd with KMnO treted mngos (Illeperum nd

7 8 E. Bl nd S. Celik Jysuriy, ). The totl chlorophyll content is n importnt qulity prmeter of kiwifruit nd decrese in ripening period (Fuke et l., 98; Krcli, ). In the first period of storge, rpid increse in chlorophyll destruction decresed towrds the end of the storge. These findings re corroorted y Thompson (). The lower rte of decrese in chlorophyll content of SA nd KMnO treted fruits could e ttriuted to e slower ripening. Ozer et l. (997) pointed out tht storge of MA nd CA conditions, chlorophyll content of kiwifruit significntly decresed with storge time. The dt concerning scoric cid content of kiwifruits incresed initilly nd then decresed with the increses in storge period. These results confirmed those of other workers (Mnolopoulou nd Ppdopoulou, 998; Ozer et l., 997). SA +K tretment in first yer nd SA tretment in second yer hd the highest scoric cid contents t the end of the storge. In these tretments decresed slower scoric cid content my e relted to e lowered the ctivity of the enzymes nd prevented oxidtion of scoric cid. Tsy et l. (98) showed tht continuing of respirtion in kiwifruits led increse in ethylene content nd decrese in scoric cid content. During the storge, strch is converted to solule sugrs in kiwifruits. After hrvest nd during storge nd ripening of the fruits the content in reducing sugrs ws incresed in prllel with the TSS content. Results re consistent with those reported y Mnolopoulou nd Ppdopoulou (998). There ws slower increse in reducing sugr in SA nd KMnO tretments which cused slowdown of ripening. Similr oservtion ws reported with SA treted nn (Srivstv nd Dwivedi, ). Preferred tsting kiwifruit hve n idel comintion of sugrs, orgnic cids nd rom voltiles in the ripe fruit (Lncster, ). In study, SA nd KMnO tretments inhiited ethylene iosynthesis nd delyed the senescence. SA. +K nd SA +K tretments hd the highest points in degusttion tests in oth yers. This work supports studies tht showed SA tretments cn retrd ripening in storge of nn nd pech (Srivstv nd Dwivedi, ; Hn et l., ). KMnO sored ethylene gs in MAP nd incresed posthrvest life of kiwifruits. These results confirmed those of other workers (Illeperum nd Jysuriy, ; Kucuk, 6). Conclusions In conclusion, the reserch indictes tht SA nd KMnO tretments, lone or in comintion, is effective methods of extending the shelf life of kiwifruits in storge. The most effective tretment in reducing losses of fruit qulity ws found to e SA +K nd SA +K tretments during the long storge period of kiwifruit. It ws determined tht under these conditions Hywrd kiwifruit cn e stored for dys without losing much of its qulity. References Arnon, D. I., 99. Copper enzymes in isolted chloroplst, polyphenoloxidse in Bet vulgris. Plnt Physiology, : -. Arpi, M. L., J. M. Lvitch, C. Greve nd A. A. Kder, 987. Chnges in cell wll components of kiwifruit during storge in ir or controlled tmosphere. J. Am. Soc. Hort. Sci., : 7-8. Bl, E. nd D. Kok, 7. Effects of uv-c nd slicylic cid on qulity of muskule tle grpes during cold storge. J Applied Hort., 9 (): 7- (Tr). Beever, D. J. nd G. Hopkirk, 99. Fruit development nd fruit physiology in kiwifruit science nd mngement. I. J. Wrrington G. C. Weston, eds., Ry Richrds, Aucklnd, pp Cstro, J. V., L. B. Pfffench, C. R. L. Crvlho nd C. J. Rossetto,. Effects of film pckging nd cold storge on posthrvest qulity of tommy tkýns mngoes. In: F. Mencrelli, P. Tonutti (Editor), V. Interntionl Posthrvest Symposium, Itly, June,. ISHS Act Hort., 68: 6. Cemeroglu, B., 7. Food nlysis. Society of Food Technology Pulictions, Ankr, Turkey, pp.

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