Effect of Long-term Controlled Atmosphere Storage on Fruit Quality in Heidi Mango

Transcription

1 Effect of Long-term Controlled Atmosphere Storge on Fruit Qulity in Heidi Mngo S.A. Oosthuyse HortReserch SA, P.O. Box 3849, Tzneen 0850 ABSTRACT Heidi mngoes were hrvested t the conventionl stge of mturtion, nd lter when t n dvnced stge of mturtion. Following the commercil pckline tretment, the fruit were either plced under controlled tmosphere storge nd refrigertion, or under norml refrigertion. 12.SoC ws dopted s the storge temperture. After 21 dys, the mngoes were llowed to ripen t 20 C under norml tmosphere. In ech fruit, qulity ws ssessed on ripening. The mngoes hrvested t n dvnced stge of mturtion did not pper to benefit from tmosphere storge. Pulp browning in these fruit ws elevted. In the fruit hrvested t the conventionl stge of mturtion, tmosphere storge reduced surfce scld, pulp browning nd internl brekdown, nd enhnced shelf-life nd tste. In view of these results, the semi-commercil doption of controlled tmosphere storge in Heidi mngo is recommended for the coming seson. Heidi mngoes develop skin nd pulp injury when plced in cool-storge for prolonged periods. The pulp becomes brown nd the skin develops drkened indenttions which re referred to s surfce scld (Fig. 1). Scld severity ws previously found to negtively correlte with storge temperture (do, unpublished). Skin nd pulp discolourtion hve been scribed to chilling injury in mngo (Medlicott et l., 1986; Medlicott nd Jger, 1987; Chplin, 1987; Lizd, 1991). It hs been found tht sensitivity to chilling injury in mngo decreses with stge of mturtion t hrvest (Thompson 1971; Medlicott et l., 1990; Medlicott et i., 1990b). Pckline hot-wter tretment (50 C for 5 minutes) ws previously shown to reduce, but not to prevent, scld development during cool-storge (Oosthuyse, 1996). Controlled tmosphere storge of mngoes hs been found to be beneficil. A dely in ripening hs been shown by number of reserchers (Feng et l., 1991; Yhi nd Vzquez-Moreno, 1993; Gonzlez-Aguilr et l., 1995; Noomhorm nd Tisuwn, 1995, 1988). It hs been shown to reduce chilling injury (O'Hre nd Prsd, 1993) nd posthrvest disese mnifesttion (Feng et l., 1991 ) in mngo. "Extreme" tmosphere exposure for short period my be effective s n insect disinfesttion tretment for mngo fruits (Yhi nd Tizndo-Hernndez, 1993; Yhi nd Vzquez-Moreno, 1993; Yhi et l., 1995). The min im of the present study ws to determine the effect of controlled tmosphere storge (CA) on surfce scld nd internl nd peripherl browning in Heidi mngo. The effect of tmosphere storge on shelf-life nd vrious other qulity ttributes of relevnce ws lso determined, nd differences in reltion to stge of mturtion t hrvest were considered. Two similr experiments were performed (referred to s Expt. I nd Expt. II). Fruit were hrvested from n orchrd block t Hmwsh (close to Tzneen) on Mrch 5 (Expt. I) nd on Mrch 19, 1997 (Expt. II). Sixty fruit were hrvested, given the commercilly dopted pckline tretment [fruit respectively wshed in 1% sop solution (By-Prox), dipped in hot-wter t 50 C for 5 minutes, dipped in prochlorz (180 ml Omeg/lOOl H20) for 20 seconds, nd hnd wxed with TAG], nd plced in cool-storge t 12.5 C for three dys [storge under norml tmosphere for three dys prior to storge under tmosphere ws done to effect commercil representtion, Le., pre-storge t pckhouse, followed by refrigerted trucking to Cpe Town hrbour, followed by cool-storge until ship loding when controlled tmosphere storge would commence]. After this period of cool-storge, 20 rndomly selected fruits were plced in ir contining C02 t low concentrtion (Atmos. 1), nd 20 rndomly selected fruits were plced in ir contining C02 t high concentrtion (Atmos. 2). The remining fruits were stored in norml ir (controls). All of the fruits were plced in cool-storge [in cool-storge room, the fruit under tmosphere being in especilly designed Trnsfresh bins] for further 18 dys, fter which they were plced, under norml tmosphere, in well ventilted lbortory mintined t 20 C (±I C) to continue ripening. During the ltter period, the stge of ripening of ech fruit ws ssessed dily with densimeter (Heinrich Breiss, Oberdischingen, Germny). Ech fruit ws evluted when it ws firm-ripe (densimeter reding of less thn 60 nd greter thn 40). The dte on which ech fruit ws evluted ws recorded to ssess shelf-life.

2 A completely rndomized design, (comprising 20 single fruit replictes of three tretments), ws employed. for such n nlysis. Dt trnsformtion ws performed when deemed necessry. Experiment II Expt. II ws identicl to Expt. I, except tht 108 fruit were hrvested, nd the tmosphere high in C02 differed with respect to C02 concentrtion (new tmosphere referred to s Atmos. 3). There were 36 single fruit replictes of three tretments. Fruit qulity evlution Fruit evlution on ripening comprised the following: Skin colour in ech fruit ws rted. A rting of "0" ws given when signs of skin colourtion were bsent, rting of"l" if trnsition to lighter green ws pprent, rting of "2" if regions of the skin hd become yellow but the totl re which ws yellow ws less thn the totl re which ws green, rting of "3" if regions of the skin hd become yellow nd the totl re which ws yellow exceeded the totl re which ws green, or rting of "4" if the skin ws completely yellow. The skin re covered with red-blush ws not considered. Disese mnifesttion in ech fruit ws rted ccording its severeness. A rting of "0" ws given if fruit ws disese free, rting of "1" if symptoms were present but were loclized to smll portion of the fruit's surfce, rting of "2" if pproximtely 1/3 of the fruit's surfce showed symptoms, rting of"3" if 2/3 ofthe fruit's surfce ws ffected, or rting of "4" if the entire fruit's surfce ws visibly disesed. The diseses occurring were lso identified. Lenticel dmge, blotch (green ptchiness of skin) nd surfce scld were rted by pproximting the percentge of the skin surfce over which symptoms could be seen. The percentges designted were either 0, 25, 50, 75 or 100. To ssess internl qulity in ech fruit, ech ws first cut through twice; 'longitudinlly' long the flttened mrgins of the seed. In ech fruit, juice from the 'cheeks' thus obtined ws evluted by mesuring its ph (Mettler Toledo 120 ph meter) nd totl soluble solids content (Euromex RF 0232 hnd held refrctometer), nd by ssessing its tste. Tste ws rted. A rting of "1" ws given if tste ws deemed ppeling, rting of "0" if tste ws deemed stisfctory but not ppeling, or rting of" -1" if tste ws deemed unstisfctory. Mesocrp colour, Le., the degree of colour intensifiction of the mesocrp from white to the yellow/ornge colour normlly seen in fully ripe Heidi mngo, ws estimted with the Heidi "blck" colour chrt. Physiologicl disorder mnifesttion in ech fruit ws rted s ws disese mnifesttion, except tht the degree to which the mesocrp s opposed to the exocrp (skin) ws ffected, ws tken into ccount. The disorders occurring were lso identified. Anlysis of vrince incorporting multiple rnge testing (5% LSD) ws employed, when the dt ws suitble Stges of mturtion t hrvest The pulp of the fruit in Expt. I ws light yellow t hrvest [index 0.1 (± 0.2)], nd the pulp of the fruit in Expt. II ws more intense yellow t hrvest [index 0.3 (± 0.2)]. An index vlue of 0.1 to 0.2 indictes the recommended stge of mturtion t which to hrvest Heidi mngoes. Atmos. 1 reduced surfce scld in Expt. I, nd Atmos. 3 reduced surfce scld in Expt II (Fig. 2). The fruit in Expt. II ppered to be less prone to this disorder. Atmos. 2 in Expt. I incresed shelf-life by pproximtely two dys (Fig. 3). Differences in shelf-life relting to tretment were not pprent in Expt. II. Atmos. 1 in Expt. I mrkedly enhnced tste (Fig. 4). This difference could not be explined in terms of differences in totl soluble solids content nor in terms of differences in ph (dt not shown). Differences in tste relting to tretment were not pprent in Expt. II. Internl brekdown (jelly-seed or soft-nose) Atmos. 1 in Expt. I reduced the severity of internl brekdown (Fig. 5). Differences relting to tretment were not pprent in Expt. II. Peripherl browning Atmos. 1 in Expt. I reduced the severity of peripherl browning (browning of the pulp just beneth the skin) (Fig. 6). The severity of peripherl browning ppered to be slightly elevted in Expt. II. Differences relting to tretment were not pprent in Expt. II. Pulp colour Atmos. I in Expt. I incresed pulp colour slightly (Fig. 7). Differences in pulp colour relting to tretment were not pprent in Expt. II. The incidence of blotch ws low. Blotch ppered to be slightly more prevlent in Expt. II. Atmos. 3 in Expt. II slightly incresed the severity of blotch. Differences in blotch severity relting to tretment were not pprent in Expt. I.

3 Surfce Scld (%) hrvest dte: Mrch5 Mrch Ii 35 ~30! 25 ~ 20 ~ 15 Fig. 2 Severity of surfce scld on ripening (left: Expt. I; right: Expt. II). In ech experiment, brs heded by differing letters differ significntly ccording to LSD (5%). Sbelf-life hrve.st dte: Mrch 5 Mrch 19 Tste Mrcb19 b b, ~ " 0.6 c 0.5.: b Fig.3 Shelf-life fter cool-storge t 12.5 C. (left: Expt. I; right: Expt. II). In ech experiment, brs heded by differing letters differ significntly ccording to LSD (5%). Internl Brekdown hrvest dte: Mrch 5 Mrch 19 Fig. 4 Tste on ripening. (left: Expt. I; right: Expt. II). In ech experiment, brs heded by differing letters differ significntly ccording to LSD (5%). Peripherl Browning I"'",.st dt.: Mrch 5 Mrch 19 j.~ 2.5 j 1.5 t 1 '" ]" 2.5., Fig. 5 Severity of internl brekdown on ripening ("softnose" nd jelly-seed ") (left: Expt. I; right: Expt. II). In ech experiment, brs heded by differing letters differ significntly ccording to LSD (5%). Pulp Colourtion ho"'.st dt.: Mrch 5 Mrch Fig. 6 Severity of peripherl browning (browning of the pulp just beneth the skin) on ripening ("soft-nose" nd jelly-seed ") (left: Expt. I; right: Expt. II). In ech experiment, brs heded by differing letters differ significntly ccording to LSD (5%). Blotcb h.",.st dt.: Mrch 5 Mrch 19 i 0.8 c b b "~ c 2.5.~.~ 0.6! 2 ~k 0.4 1:. '* 1.5 ;; Fig. 7 Pulp colour on ripening (left: Expt. I; right: Expt. II). In ech experiment, brs heded by differing letters differ significntly ccording to LSD (5%). Fig. 8 Blotch severity on ripening (left: Expt. I; right: Expt. II). In ech experiment, brs heded by differing letters differ significntly ccording to LSD (5%).

4 Differences relting to tretment nd experiment (mturtion) in lenticel dmge, ground skin colourtion, totl soluble solids content, ph, nd internl browning were not pprent (dt not shown). Controlled tmosphere storge did not show ny cler benefit in the fruit hrvested t n dvnced stge of mturtion (Expt. II). These fruit generlly showed greter degree of pulp browning thn the fruit hrvested erlier (those in Expt. I). In the fruit hrvested t the conventionl stge of mturtion (those in Expt. I), tmosphere storge reduced surfce scld, pulp browning nd internl brekdown, nd enhnced shelf-life (reduced ripening rte) nd tste. O'Hre, nd Prsd (1993) specificlly ssocited the llevition of chilling injury symptoms to enhnced C02 tmospheres. In their study, reduced 02 concentrtions hd no significnt effect on chilling injury. Reports on reductions in ripening rte during controlled tmosphere storge re numerous. However, specific tmospheres re required for norml ripening of mngoes during nd fter controlled tmosphere storge. Unsuitble tmospheres my give rise to nerobic respirtion (O'Hre nd Prsd, 1993; Bender et t., 1994), nd to n elevted cid content on ripening (McLuchln et t., 1994). An enhncement in tste following tmosphere storge hs lso been found in fig (Turk et t., 1994), pple (Jnkovic nd Drobnjk, 1992), kiwifruit (Swd et t., 1993) nd plum (Ben nd Gwed, 1992). Storge of vrious fruit types in specific tmospheres is likely fvour biochemicl processes which enhnce tste ppel. A reduction in internl brekdown following tmosphere storge ws lso found in plum (Ben nd Gwed, 1992; Truter nd Combrink, 1992; Argent et t., 1994); nd nectrine (Lurie, 1992; Lurie et t., 1992). Controlled tmosphere storge hs been found to retrd cell membrne degrdtion (Wng nd Herner, 1989; Deschene et t., 1991). The reduction in internl brekdown found might thus be scribed to the mintennce of membrne integrity by controlled tmosphere. In view of the beneficil results obtined in the present study, semi-commercil se export of Heidi mngoes under tmosphere might be considered. Further experiments, to show the effects of controlled tmosphere storge on mngoes grown in South Afric for export, re to be performed during the coming seson. Thnks re due to Trnsfresh Afric for the provision of equipment nd for sponsoring this study. This project ws not sponsored by the South Africn Mngo Growers' Assocition. ARGENTA, L.C, BRACKMANN, A, AND MON- DARDO, M Posthrvest qulity of pples stored t different tempertures nd C02 nd 02 concentrtions. Revist Brsileir de Fisiologi Vegetl 6: BEN, J. AND GAWEDA, M The effect of incresing concentrtion of crbon dioxide in controlled tmosphere storge of plums cv. Wegierk Zwykl (Prunus domestic L.). II. Chnges in the content of soluble sugrs, orgnic cids nd totl phenols in the spect of fruit tste. Act Physiologie Plntrum 14: BEN, 1. AND GA WEDA, M Effect of incresing concentrtions of C02 in controlled tmosphere storge on the development of physiologicl disorders nd fungl diseses on plums (Prunus domestic L.). Foli Hort. 4: CHAPLIN, G.R Ripening in mngo fruit nd its mnipultion by low temperture. In RT. Prinsley nd G. Tucker, eds. Mngoes - review. Commonwelth Science Council, London. DESCHENE, A, PALIYATH, G., LOUGHEED, E.C, DUMBROFF, E.B., AND THOMPSON, J.E Membrne deteriortion during posthrvest senescence of broccoli florets: modultion by temperture nd controlled tmosphere storge. Posthrvest Biology nd Technology 1: FENG S.Q., CHEN YX., WU H.Z., AND ZHOU S.T The methods for delying ripening nd controlling posthrvest diseses of mngo. Act Agriculture Universittis Pekinensis 17: GONZALEZ-AGUILAR, G., VASQUEZ, C, FELIX, L., BAEZ, R, SILLER, J., AIT-OUBAHOU, A, AND EL- OTMANI, M Low 02 tretment before storge in norml or modified tmosphere pckging of mngo. Proceedings of n interntionl symposium held t Agdir, Morocco, Jnury JANKOVIC, M. AND DROBNJAK, S The influence of the composition of cold room tmosphere on the chnges of pple qulity. Prt 1. Chnges in chemicl composition nd orgnoleptic properties. Review of Reserch Work t the Fculty of Agriculture, Belgrde 37: LURIE, S Controlled tmosphere storge to decrese physiologicl disorders in nectrines. Interntionl Journl of Food Science nd Technology 27: LURIE, S., ZEIDMAN M., ZUTHI, Y, AND BEN ARIE, R Controlled tmosphere storge to decrese physiologicl disorders in peches nd nectrines. Hssdeh 72: MEDLICOTT, AP. AND JAGER, MJ The development nd ppliction of post-hrvest tretments to mnipulte ripening in mngoes. In R.T. Prinsley nd G. Tucker, eds. Mngoes - review. Commonwelth Science Council, London. MEDLICOTT, AP., SIGRIST, 1.M.M., AND SY, O Ripening of mngoes following low temperture storge. 1. Amer. Soc. Hort. Sci. 115: MEDLICOTT, AP., N'DIA YE, M., AND SIGRIST, J.M.M. 1990b. Hrvest mturity nd concentrtion nd exposure time to cetylene influence initition of ripening in mngos. J. Amer. Soc. Hort. Sci. 115:

5 NOOMHORM, A., AND TIASUW AN, N Effect of controlled tmosphere storge for mngo. Americn Society of Agriculturl Engineers, No , p. 8. NOOMHORM, A., AND TIASUWAN, N Controlled tmosphere storge of mngo fruit, Mngifer indic L. CY. Rd. Journl of Food Processing nd Preservtion 19: O'HARE, TJ., AND PRASAD, A The effect of temperture nd crbon dioxide on chilling symptoms in mngo. Act-Hort. 343: OOSTHUYSE, S.A Effect of pckline hydro-heting tretments on Heidi fruit qulity fter four weeks of coldstorge. S.A. Mngo Growers' Assoc. Yerbook 16:6-11. SAWADA, T., SEO, Y., AND MORISHIMA, H Studies on storge nd ripening of kiwifruit. Prt 3. Journl of the Jpnese Society of Agriculturl Mchinery 55: THOMPSON, A.K The storge of mngo fruits. Trp. Agric. 48: TRUTER, A.B. AND COMB RINK, J.e Controlled tmosphere storge of peches, nectrines nd plums. J ournl of the Southern Africn Society for Horticulturl Sciences 2: TURK, R., ERIS, A., OZER M.H., TUNCELLI, E., AND SASS, P Reserch on the CA storge offig CY. Burs Siyhi. Act Hort. 368: WANG, H. AND HERNER, R.e Effect of CA storge on the ultrstructure of chloroplsts nd chlorophyll content of Chinese mustrd. Proceedings of the Fifth Interntionl Controlled Atmosphere Reserch Conference, Wentchee, Wshington, USA, June, 2:9-17. YAHIA, E.M., AND TIZNADO-HERNANDEZ, M Tolernce nd responses of hrvested mngo to insecticidl low-oxygen tmospheres. HortScience 28: YAHIA, E.M., AND VAZQUEZ-MORENO, L Responses of mngo to insecticidl oxygen nd crbon dioxide tmospheres. Lebensmittel Wissenschft und Technologie 26: YAHIA, E.M., KUSHWAHA, L., SERWATOWSKI, R., AND BROOK, R Insecticidl tmospheres for tropicl fruits. Proceedings of the Interntionl Conference, Gunjuto, Mexico, Februry, 'RODNEY COOPE'R ESTAIT P.O. BOX 3901 TZANEEN 0850 The Mngo Nursery for your selection of cultivr Plce your order now not to be disppointed When the telkom lines re not stolen Contct: Rodney Cooper on TELIFAJ(015) AIH (015) or on eel