Analytical CHEMISTRY

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1 ISSN : Volume 15 Issue 4 Anlytil CHEMISTRY An Indin Journl Full Pper ACAIJ, 15(4) 2015 [ ] Proessin nd shelf-life ssessment of mixed-fruit juie from pinepple, orne, pw-pw nd uv Collins N.Uonu, Anthoni E.Uzoukwu, Justin N.Nwosu, Ijeom Olwuni Deprtment of Food Siene & Tehnoloy, Federl University of Tehnoloy Owerri, P. M. B. 1526, Owerri, (NIGERIA) E-mil: piety4ood@yhoo.om ABSTRACT Mixed fruit juie ws produed with pinepple (40%), orne (30%), pwpw (20%) nd uv (10%). Different smples of the produt were treted (preserved) with different levels (0.04%, 0.06% nd 0.08%) of sodium enzote, psteurized nd stored on mient shelf for three months. ph, titrtle idity, solule solids, sori id nd totl miroil ount were nlyzed on the fresh nd stored smples t one nd three months. ph of ll the smples sinifintly (P 0.05) deresed with dded enzote durin store. Titrtle idity for the smples inresed fter three months. Totl solule solids (rix) deresed with store nd ddition of enzote ut insinifintly, while rix/id rtio sinifintly deresed with dded enzote nd store period from (in fresh smple) to (fter three months); 16.0 to nd to for smples with 0.04%, 0.06% nd 0.08% enzote respetively. Asori id ontent lso showed sinifint derese in ll smples, nd smple preserved with 0.8% enzote retined hihest sori id ontent nd lowest miroil ount (Shromyes erevisie nd Ltoillus speies) fter 3 months store. Stphyloous ureus nd Peniillum speies were identified in the ontrol nd 0.04%-enzote-preserved smples. Overll eptility result etween the fresh nd stored smples showed insinifint differene Trde Siene In. - INDIA KEYWORDS Mixed-fruit; Juie; Proessin; Shelf-stility; Preservtive. INTRODUCTION A mixed fruit juie is the unfermented, thouh fermentle liquid extrted from two or more sound ripe fruits intended for diret onsumption s otined y mehnil proess [1]. Fruit juies re ood soures of ertin vitmins espeilly vitmin C nd thus do supplement for the defiieny of these vitl nutrients in our strh-loded diet. Inidentlly, Nieri is endowed with mny indi- enous tropil fruits, most of whih suh s orne, mno, pinepple, uv nd shew hve ret potentil for ommeril juie prodution [2]. The vilility of these rw mterils notwithstndin, so muh is spent on importtion of fruit produts. Okonkwo et l. [3] lmented the lrmin rte of importtion of fruit produts nd the wste ssoited with its low level of industril utiliztion in developin ountries. Unfortuntely, most of wht Nieri imports s fruit juies n only qulify for netrs lookin t their ontents. Aprt from retin vriety nd

2 ACAIJ, 15(4) 2015 onveniene, lendin of fruit juies offers the opportunity of djustin flvour, olour, visosity defets nd orretin juie omposition. Besides, s the onsumer demnd for sfe, stle nd fresh-like produts ontinue to inrese, it eomes neessry to develop eptle fresh-like nd shelfstle fruit juies tht will stisfy the onsumer demnd. Thouh, some reserh works hve een done on the nutrient omposition of fruit juies, there is little or no informtion on the shelf-life ssessment of mixed fruit juies preserved with different onentrtion of sodium enzote. The ojetives if this reserh were to produe mixed fruit juie from these tropil fruits, determine its physiohemil properties, miroil nlyses, shelfstility nd sensory eptility of the mixed fruits juie. Colletion of mterils MATERIALS The fruits (pinepple, orne, pw-pw nd uv) used for the mixed fruit juie prodution were purhsed from Eke Ukwu min mrket in Owerri Muniipl, Imo Stte. Chemil reents The hemil reents of nlytil rdes used for the vrious nlyses were otined from the Food Siene nd Tehnoloy lortory of Federl University of Tehnoloy, Owerri. METHOD OF PRODUCTION OF MIXED FRUIT JUICE The fruits were seprtely wshed, peeled, ut nd fed into srew press. Eh fruit ws pressed out seprtely, olleted nd filtered throuh muslin loth. Different trils were done in mixin the pressed fruit juies in different proportions to produe different mixed juie formultions. These tril smples were presented to ten-mn prodution uidne pnel (PGP) to ssess the overll eptility of smples. Considerin the omments of the PGP nd the rtin of eh presented tril smple on 7-point hedoni Collins N.Uonu et l. 133 Full Pper sle (where 7 stood for very eptle nd 1 stood for very rejetle/uneptle) djustments were mde on the proportions of formultion to otin new tril smples. These smples were represented to the PGP, who fter their re-ssessment reommended prtiulr smple. The formul (40% pinepple, 30% orne, 20% pw-pw nd 10% uv) of this most eptle smple ws used in the prodution of the finl experimentl juie smples. A tril of 10 litres of freshly mixed fruit juie ws produed with this formul. Two nd hlf litres of this ws poured into eh of four trnsprent ottles nd orked. To the juie ontents of these ottles were dded either 0.0%, 0.04%, 0.06%, or 0.08% of sodium enzote s preservtive. These formed the four tretment smples. Eh stok smple ws filled into three sterilized 300ml plsti trnsprent white ottles nd psteurized t 80% for ten minutes ordin to Mire [4]. They were then orked hot nd ooled in old wter. PHYSICO-CHEMICAL ANALYSES Mesurement of ph The Jenwy ph meter, model 3510 ws used to determine the ph of the mixed fruit juies. The ph meter ws stndrdized with uffers 4 nd 7. The meter eletrode ws rinsed with distilled wter nd then dipped into the smples. The ph of the smples ws red to the nerest 0.01 units. Determintion of totl titrtle idity The method desried y AOAC [5] ws used. Twenty-five millilitres of eh smple ws introdued into onil flsk. Three drops of phenolphithlein inditor ws dded into eh flsk nd the ontents titrted with stndrdized 0.1N NOH to definite pink olour. The titrtle idity ws lulted s itri id. Totl solule solids The solule solids of the smples were mesured with the id of hnd refrtometer. One drop of the smple ws dropped on the sreen of the refrtometer prism nd the redins were tken. Anlytil CHEMISTRY An Indin Journl

3 134 Proessin nd shelf-life ssessment. of mixed-fruit juie from pinepple Full Pper ACAIJ, 15(4) 2015 Fiure 1: Flow dirm for methodoloy nd tretments pplied to mixed fruit juie CHEMICAL ANALYSIS Determintion of sori id ontent The method s desried y Onwuk [6] ws used. 10ml of the undiluted juie ws pipetted into 250ml onil flsk. 10ml of 1% oxli id ws dded to it s stilizin ent nd 2ml of etone ws dded to the mixture. This ws titrted with stndrdized indophenol solution to fint pink olour tht persisted for out 15 seonds. The volume of the stndrd dye used ws reorded nd the vitmin C ontent (Asori id) ws lulted in m per 100ml juie. MICROBIOLOGICAL ANALYSIS OF Miroioloil nlysis inluded enumertion nd identifition of miroes in the smples. The fruit juie smples were ultured usin the spred plte method desried y Urih [7] s the est for teril enumertion of food smples. The pltes were inuted t 37 O C for hours efore oservtion for totl vile ount on nutrient Ar nd totl oliform on MConkey Ar. The potto Dextrose Ar pltes for yest nd moulds were inuted for 5 dys. These pltes were mintined t required temperture nd time. Totl teril ounts were done with Gllenkmp diitl olony ounter. The men numer of olonies Anlytil CHEMISTRY An Indin Journl ounted ws expressed s Colony Formin Units (fu)/ ml. Suulture ws rried out to otin pure isoltes nd disrete olonies. Identifition of ornisms ws done sed on morpholoil, iohemil nd ulturl hrteristis. Bteril isoltes were nlyzed for Grm hrter nd their motility nd vrious iohemil tests were performed y inoultin smll portion of well-isolted olony into series of medi suh s sur fermenttion, tlse test, oulse test, itrte test, oxidse nd indole tests [7]. Funi isoltes were hrterized on the sis of pimenttion, sporultion, myeli rrnement nd mirosopilly [8]. The identities of the isoltes were onfirmed with referene to stndrd terioloil nd myoloil mnuls [9]. SENSORY EVALUATION OF MIXED FRUIT JUICE The mixed fruit juie smples were presented to twenty-mn pnel t different keepin periods. The freshly prepred mixed juies were lso ompred with juies stored for one month nd three months respetively, sed on their olour, flvour nd overll eptility. A nine-point hedoni sle ws used for these tests. The sores otined were nlyzed sttistilly to determine ny sinifint differene etween the mixed-juie produts. Sttistilly, the lest sinifint differene method ws used to seprte the mens nd identify differenes in the olour, flvour nd overll

4 ACAIJ, 15(4) 2015 Collins N.Uonu et l. 135 Full Pper TABLE 1 : Men ph vlues of mixed fruit juie smples Mixed juie with 0.04% sodium enzote Mixed juie with 0.06% sodium enzote d 3.80 e Mixed juie with 0.08% sodium enzote 3.70 f Mens on the sme olumn with different susripts re sinifintly different t (P 0.05) nd Mens on the sme row with different susripts re sinifintly different t (P 0.05). TABLE 2 : Men titrtle idity vlues of mixed fruit juie smples Mixed juie with 0.04% sodium enzote Mixed juie with 0.06% sodium enzote 0.65 d 0.68 e 0.70 f Mixed juie with 0.08% sodium enzote h 0.77 i Mens on the sme olumn with different susripts re sinifintly different t (P 0.05) nd Mens on the sme row with different susripts re sinifintly different t (P 0.05). eptility of the fresh nd stored smples. RESULTS AND DISCUSSION Effet of preservtive onentrtion on ph vlues of mixed fruit juie The freshly produed mixed fruit juie smples produed from Pinepple, Orne, Pw-pw nd Guv hd ph vlues in the rne of 3.70 to 3.96 (TABLE 1). The sinifint (P 0.05) vrition in the ph, understndly ws due to the dded sodium enzote, whih is n idulnt. After one month of store t mient tempertures, ll smples exept the mixed juie preserved with 0.04% sodium enzote deresed sinifintly (P 0.05) in ph, ompred to their oriinl fresh smples. The insinifint hne in ph vlue ( ) in the smple preserved with 0.04% sodium enzote fter one month ould e due to lower onentrtion of the dded idulnt un tht smple. There were sinifint (P 0.05) dereses in ph in other smples fter three months of store. For instne, in mixed juie with 0.06% sodium enzote, the ph deresed from vlue of 3.90 to vlue of 3.80 fter three months store. Effet of preservtive onentrtion on the titrtle idity of mixed fruit juie smples Expetedly, the titrtle idity of the freshly mixed juie nd stored smples inresed with the mount of dded enzote. The vritions in titrtle idity in the juie smples were sinifint (P 0.05) (TABLE 2). The dereses in ph is refleted in the inreses in titrtle idity vlues. Similr results were otined in some previous studies. Grry et l. [10] reported ph of 3.63 with titrtle idity of 0.52 for fresh mixed pple-lue erry juie nd ph of 3.61 with titrtle idity vlue of 0.54 fter three months of mient shelf store for the sme mixed juie. This indited tht the trend of derese in ph with inrese in titrtle idity s oserved in this study is in reement with the results of previous studies. Effet of preservtive onentrtion on solule solids (Brix) of mixed fruit juie smples The totl solule solids (mesured in deree Brix) of the freshly produed mixed juie, with preservtive were etween to O Brix (TABLE 3). Considerin the reommendtion of Btes et l. [11], fruit juie should not e hiher thn 18 O Brix or less thn 6 O Brix. Bevere less thn 6 O Brix were deemed wek or wtery. The smples in this study, thouh moderte in solule solids, were suitle for ommeril fruit juie produts, with rerds to solule solids ontents, more so when more onsumers re voidin very sweet everes. Hiher solule solids for fruit juies my result to hiher deree of sweetness when the id is onstnt. The vlues of solule solids ( O Brix) deresed Anlytil CHEMISTRY An Indin Journl

5 136 Proessin nd shelf-life ssessment. of mixed-fruit juie from pinepple Full Pper with ddition of sodium enzote nd inresed in store period, thouh the derese ws not sinifint (P>0.05), lowerin from fresh juie vlue of to fter one month of store, to vlue of 10.0 fter three months of mient shelf store for the smple with 0.04% sodium enzote. Effet of preservtive onentrtion on the Brix/ id rtio of mixed fruit juie smples The Brix/Aid rtio of ll the mixed juie smples deresed sinifintly t (P 0.05) with inresin onentrtion of sodium enzote nd store period, (TABLE 4). Relizin tht the more the mount of preservtive or idulnt (dded or synthesized) in the juie, the less the Brix/Aid rtio, then lower Brix/Aid rtio indites lower level of juie sweetness, tendin to sourness. The Brix/Aid rtio is n importnt qulity ftor for the flvour of juies nd some other everes [12], nd sine the solule solid ontents (rix) of the smples were reltively stle, the sinifint vrition in Brix/Aid rtio ould e ttriuted to the dded idulnts. Effet of preservtive onentrtion on sori id ontents (m/100ml) of mixed fruit juie smples The sori id ontent of the freshly produed mixed juie smples rned from m/ Anlytil CHEMISTRY An Indin Journl TABLE 3 : Men solule solids vlues of mixed fruit juie smples ACAIJ, 15(4) 2015 Mixed juie with 0.04% sodium enzote Mixed juie with 0.06% sodium enzote Mixed juie with 0.08% sodium enzote Mens on the sme olumn with different susripts re sinifintly different t (P 0.05) nd Mens on the sme row with different susripts re sinifintly different t (P 0.05). TABLE 4 : Men rix/id rtio vlues of mixed fruit juie smples Mixed juie with 0.04% sodium enzote Mixed juie with 0.06% sodium enzote d e f Mixed juie with 0.08% sodium enzote h i Mens on the sme olumn with different susripts re sinifintly different t (P 0.05) nd Mens on the sme row with different susripts re sinifintly different t (P 0.05). 100ml ut the fiures did not indite rel inreses. Wht ws oserved miht e n idulnt effet on the stility of the vitmin. After one month nd three months of store t mient tempertures, the sori id ontents of ll the mixed juie smples deresed sinifintly (P 0.05). The sori id ontent deresed from 38.68m/100ml to 28.63m/100ml fter one month nd to 10.50m/100ml fter three the sori id ontents of ll the mixed juie smples deresed sinifintly (P 0.05). The sori id ontent deresed from 38.68m/100ml to 28.63m/100ml fter one month nd to 10.50m/100ml fter three months store in the smple preserved with 0.04% sodium enzote. It ws lso oserved tht the smple preserved with 0.08% sodium enzote retined more sori id thn other onentrtions. It deresed from 38.71m/100ml in freshly produed smple to 29.85m/100ml fter one month store to 12.00m/ 100ml fter three months store, whih showed tht the smple preserved with 0.08% sodium enzote retined out 31% of its sori id ontent while tht preserved with 0.06% idulnt retined 29% of its sori id fter three months of mient store. Thouh this is low, it n still serve s soure of vitmin in our strh-loded diet. The derdtion of sori id ws reported y Ny nd Shw [13] to e used y oxidtion, hih temperture nd other unondusive store onditions.

6 ACAIJ, 15(4) 2015 Collins N.Uonu et l. 137 Full Pper TABLE 5 : Men sori id vlues of mixed fruit juie smples Mixed juie with 0.04% sodium enzote Mixed juie with 0.06% sodium enzote f Mixed juie with 0.08% sodium enzote h i Mens on the sme olumn with different susripts re sinifintly different t (P 0.05) nd Mens on the sme row with different susripts re sinifintly different t (P 0.05). TABLE 6 : Bteri identified in the mixed juie smples Ltoillusspeie Ltoillusspeie Mixed juie with 0.0% Sodium enzote Ltoillus speie Stphyloous ureus Stphyloous ureus Ltoillusspeie Ltoillusspeie Mixed juie with 0.4% Sodium enzote Ltoillus speie Stphyloous ureus Stphyloous ureus Mixed juie with 0.8% Sodium enzote Ltoillus speie Ltoillus speie Ltoillus speie Mixed juie with 0.6% Sodium enzote Ltoillus speie Ltoillus speie Ltoillus speie The totl miroil ounts for the mixed fruit juie smples stored for three months The totl teril ounts for the freshly prepred smples (with preservtive) rned from 1.2 X 10 3 to 2.9 X 10 3 fu/ml (TABLE 5). These vritions in vlues ould not e explined esides equipment/hndlin ontmintion, thouh ll the fresh smples hd very eptle level of miroil lod. The smples with 0.04% sodium enzote, hd hiher rte of miroil rowth, with teril ount inresin from 2.9 X 10 3 to 2.6 X 10 4 t one month store period nd to 3.5 X 10 5 t 3 months store period s ompred to the smples preserved with 0.08% sodium enzote whose teril ount ws reltively stle, inresin from 1.2 X 10 3 to 3.8 X 10 3 t one month store period nd to 4.8 X 10 3 t 3 months store period. It ws oserved tht the 0.08% level of sodium enzote effetively heked funl rowth for the store period studied. These smples mintined the totl funl lod of 1.0 X 10 1 fu/ml up to 3 months store period. Thus, this preservtive level should e reommended for the preservtion of this produt for its effetiveness in ontrollin oth totl teril nd funl rowth in the produt. This view ws held euse the mximum totl miroil ount reommended for sinle strenth nd mixed juie smples is 1.0 X 10 5 fu/ml [14]. The ontrol smple whih hd no dded preservtive (sodium enzote) hd the hihest miroil lod mon ll the smples s fresh nd t periods of store. It inresed from 3.5 X 103 in the freshly produed mixed juie to 7.5 X 10 5 t one month store to 9.8 X 10 6 t 3 months store. This showed tht the freshly produed mixed juie n e tken without preservtive within few hours of prodution, ut eomes unsfe when stored sine the vlues re ove the eptle miroil lod level (1.0 X 10 5 fu/ml) in fruit juies. The teri identified in the freshly produed mixed fruit juie smples for ll levels of tretment (preservtive) were ltoillus speie (TABLE 6). Stphyloous ureus ws identified in the ontrol nd 0.04% enzote treted smples stored for 1 nd 3 months. While ltoillus is ommon teri used in lti id fermenttion, the inidene of Stphyloous ureus in these other smples is onsidered sfety risk sine it hd een ssoited with food orne illnesses [15]. Peniillum, whih is onsidered food spoile ornism [16] ws identified in ll the stored smples exept the one preserved with 0.08% sodium enzote. This suests tht the fruit juie produt for store, required up to 0.08% sodium enzote (s preservtive) to e shelf-stle nd wholesome for the store period of three months. The non-identifition of ny oliform or pthoen in the mixed juies preserved with 0.06% nd 0.08% sodium enzote ws not surprisin sine, Hther et l. [14] reported tht the ph of most Anlytil CHEMISTRY An Indin Journl

7 138 Proessin nd shelf-life ssessment. of mixed-fruit juie from pinepple Full Pper Mixed juie with 0.0% Sodium enzote Mixed juie with 0.4% Sodium enzote Mixed juie with 0.8% Sodium enzote Mixed juie with 0.6% Sodium enzote TABLE 7 : Funi identified in the mixed juie smples ACAIJ, 15(4) 2015 Shromyes erevisie; Shromyes erevisie; Shromyes erevisie Peniillum; Cndid speie Peniillum; Cndid speie Shromyes erevisie; Shromyes erevisie; Shromyes erevisie Peniillum Peniillum Shromyes erevisie; Shromyes erevisie; Shromyes erevisie Peniillum; speie Peniillum; speie Shromyes erevisie Shromyes erevisie Shromyes erevisie TABLE 8 : Men sensory sores for the olour nd flvour of the mixed fruit juie smples COLOUR FLAVOUR Mixed juie with 0.04% sodium enzote Mixed juie with 0.06% sodium enzote Mixed juie with 0.08% sodium enzote Mens on the sme olumn with different susripts re sinifintly different t (P 0.05) nd Mens on the sme row with different susripts re sinifintly different t (P 0.05). fruit juies ( 4.0) is usully too low for the rowth of pthoeni teri. Shromyes erevisie ws identified in ll the smples nd the only funi in the smples preserved with 0.08% sodium enzote (TABLE 7). This onfirmed report y Ry [17] tht vrieties of Shromyes erevisie were the most ommon yests in fermented foods nd everes sed on fruit nd veetles. The funi identified in the stored ontrol smples were shromyes erevisie, peniillum, nd ndid speies. The isoltion of shromyes erevisie, peniillum, rhodotorul nd ndid speies in fruit juies ws reported y Mthews nd Monthville [16]. They stted tht ndid nd peniillum were responsile for spoile of pple under study. This ould lso e responsile for the off flvour oserved in the stored ontrol smples. of the mixed fruit juie. Sensory eptility of the mixed fruit juie smples All freshly produed smples irrespetive of the level of preservtive dded were modertely eptle (sore = 7) in olour nd flvour (TABLE 8) ut very eptle in overll eptility (TABLE 8). For ll smples, the olour of the mixed fruit juie deteriorted with inresed store period. Speifilly ll smples stored for 3 months hd sliht eptne (sore: 6). Anlytil CHEMISTRY An Indin Journl There were sinifint differenes (P 0.05) etween the olour of the freshly proessed mixed juie nd the olour of three months stored smples. There were no sinifint differenes etween the flvour sores (6.8 to 7.2), modertely eptle) for ll fresh nd stored smples. In overll eptility (TABLE 8), the freshly produed smples were preferred to ll the stored smple hvin the hihest sores ( ). Amon the sored smples, 0.08% level of sodium enzote ws more effetive in preservin the qulity of the mixed fruit juie t 3 months period of store hvin the hihest sores for ll qulity prmeters onsidered (TABLE 8) t ll store periods. CONCLUSION Modertely epted mixed fruit juie produts ws produed with pinepple, orne, pw-pw nd uv t levels of 40%, 30%, 20% nd 10% respetively. The smples were ll eptle to twenty-mn trined pnel even fter three months of store nd there ws no sinifint differene in the flvour nd overll eptility of the freshly Prepred smples nd the stored smples t (P 0.05). All the mixed juie smples preserved with 0.06% nd 0.08% sodium enzote hd miroil lod within

8 ACAIJ, 15(4) 2015 Collins N.Uonu et l. 139 Full Pper the eptle rne of 1.0 X 10 5 fu/ml [14]. The miroil lod of ll the smples preserved with 0.08% enzote ws lower thn the ones preserved with 0.06% nd 0.04% sodium enzote. Considerin the levels of sodium enzote used, the smple preserved with 0.08% sodium enzote is onsidered to e the most shelf-stle euse of the type (Ltoillus nd Shromyes) nd lod of miro-ornism identified in ll its smples. These miroes Shromyes erevisie nd ltoillus speies, re ommonly found in fruit juie produts nd hve not een reported to e hrmful to humn eins [14]. REFERENCES [1] R.P.Btes, P.E.Crndll, J.R.Morris; Tropil Fruits in: Priniples nd prties of smll nd mediumsle fruit juie proessin, Avi Pulition Co., West Port Connetiut, , (1997). [2] T.O.Akinwle, E.A.Atv, O.Olumiw; Cotte proessin of shew pple juie in Nieri, physiohemil nd sensory evlution of produt, Journl of Food Tehnoloy in Afri, 6(2), (2001). [3] W.O.Okonkwo, R.O.Okotore, A.A.Osuntoki; The loholi fermenttive effiieny of indienous yest strins of different oriin on orne juie, Afrin Journl of Biotehnoloy, 4(11), (2005). [4] D.E.Mire; Fruit nd veetle proessin, FAO Ari Servies Bulletin, 119 (2001). [5] Ao; Offiil methods of nlysis, 15 th Edition Assoition of offiil riulturl hemist, Wshinton D.C., (1990). [6] G.I.Onwuk; Food nlysis nd instrumenttion: Theory nd Prtie, Nphthli Prints, Los, (2005). [7] N.Urih; Puli helth food nd industril miroioloy, 3 rd Edition Bopeo, Benin, 307 (2004). [8] S.D.Aey; Foundtion in medil myoloy, 4 th Edition, Kenlf Pulition, Port Hrourt, Nieri, (2007). [9] J.A.Brnett, R.W.Pyne, O.Yrrow; Yest: Chrteristis nd identifition, 2 nd Edition Cmride University Press, New York (1985). [10] M.Grry, M.Justin, F.Mike; Qulity nd stility of lue erry juie lended with pple, rpe, nd rnerry juie, Journl of Food Qulity, 24(2), (2001). [11] R.P.Btes, P.G.Crndll, R.Morris; Phytohemil nd qulity ssessment of fresh nd proessed fruits nd veetles, Priniples nd prties of smll/ medium sle juie proessin (2001). [12] A.Nmutei; Effets of preservtion method nd store onditions on the flvour nd olour of pssion fruit juie, Afrin Crop Siene Journl, 6(4), (1998). [13] Ny, Shw; Tropil nd su-tropil fruits, Westport, Connetiut.Avi Pulition Co., (1993). [14] W.S.Hther, E.C.Hill, M.E.Prish, D.F.Splittstoesser, J.L.Weihe; Fruit everes, in C.Vnderznt, D.F.Splittstoesser, Edition Compendium of methods for the miroioloil exmintion of foods, Amerin Pulition Helth Assoition, Wshinton D.C., (1992). [15] H.Pen, L.Restino, L.A.Shelef, H.Spitz; Isoltion nd enumertion of Billus ereus from foods on novel hromoeni pltin medium, Food Miroioloy., 18, (2001). [16] K.K.Mthews, T.J.Montville; Priniples, whih influene miroil rowth, survivl, nd deth in foods, in M.P.Doyle, T.J.Montville, Edition Food Miroioloy Fundmentls nd Frontiers Wshinton D.C., (2000). [17] B.Ry; Fundmentl food miroioloy, CRC press, New York, (2001). Anlytil CHEMISTRY An Indin Journl