Physiological and sensory aspects of maturation, ripening, and postharvest chilling of fresh market melting- and nonmelting-flesh peach fruit

150 Pages·1997·6 MB·English

by  Brovelli, Ernesto A

PHYSIOLOGICALANDSENSORYASPECTSOFMATURATION,RIPENING,
ANDPOSHTARVESTCHILLINGOFFRESHMARKETMELTING-AND
NONMELTING-FLESHPEACHFRUIT
By
ERNUSTOA.BROVELLI
ADISSERTATIONPRESENTEDTOTHEGRADUATESCHOOL
OFTHEUNIVERSITYOFFLORIDAINPARTIALFULFILLMENT
OFTHEREQUIREMENTSFORTHEDEGREEOF
DOCTOROFPHILOSOPHY
UNIVERSITYOFFLORIDA
1997
ToCeleste
TomyfamilyinArgentina
InmemoryofCarolina
ACKNOWLEDGMENTS
IexpressmydeepestgratitudetoDr.JeffreyK.Brechtforhisguidanceandsage
advice. HegavemetheindependenceIneededtodevelopmyresearch,yethewasalways
thereformeprovidinghiscriticalandinsightfulperspective.
IalsothankDr.WayneB.Shermanforhissupportandhisunwaveringprovision
ofthegenotypesIneeded. IamalsoverygratefultoDr.CharlesA.Simsforhis
invaluableinputinmyresearchandhisopennesstotheuseofhislaboratoryandcomputer
facilities. IamalsoveryappreciativeofDr.DonaldJ.Huberand Dr.StevenA.Sargent
fortheirwillingnesstoparticipateonmysupervisorycommittee.
Mysinceregratefulnessisalsoextendedtothosewhogavemeahelpinghand
wheneverIneededit:AliciaDaniel,JayHarrison,BobGolaszewski,FeAlmira,Dr.
Dehgan,Dr.Polito,Dr O’Keefe,Dr Baldwin,Dr.Erdos,KathyBergsma, WalterJones,
ElaineSummers,CathyKelly,andAbbieFox.
iii
TABLEOFCONTENTS
Page
ACKNOWLEDGMENTS
iii
ABSTRACT vi
CHAPTERS
INTRODUCTION
1 1
2 LITERATURE REVIEW 3
Introduction 3
FruitDevelopment 3
CompositionalChangesDuringMaturationandRipening 4
ColorChangesDuringMaturationandRipening 6
PeachAroma 8
Climacteric 10
TexturalCharacteristicsofPeaches 11
ThePhysiologicalBasisforNonmeltingFlesh 13
DeterminingHarvestMaturity 14
SignificanceandInterpretationofSensoryEvaluationResults 18
FruitQualityasRelatedtoStorageTemperature 20
ChillingInjury 21
3 QUALITYPROFILEOFSELECTEDMELTING-AND
NONMELTING-PEACHGENOTYPES 27
Introduction 27
MaterialsandMethods 28
ResultsandDiscussion 33
IV
4 DEVELOPMENTALASPECTSANDPOTENTIALMATURITY
INDICESOFSELECTEDMELTING-ANDNONMELTING-
FLESHPEACHGENOTYPES 51
Introduction 51
MaterialsandMethods 52
ResultsandDiscussion 57
56 RESPONSETOPOSTHARVESTCHILLINGOF MELTING-
ANDNONMELTING-FLESHPEACHGENOTYPES 87
Introduction 87
MaterialsandMethods 89
1995Study 89
1996Study 93
ResultsandDiscussion 95
1995Study 95
1996Study 101
SUMMARYANDCONCLUSIONS 120
QualityComparisonbetweenMelting-andNonmelting-
FleshPeachGenotypes 120
DevelopmentalAspectsandPotentialMaturityIndicesof
SelectedMelting-andNonmelting-FleshPeachGenotypes 121
ResponsetoPostharvestChillingofMelting-and
Nonmelting-FleshPeachGenotypes 125
Conclusions 127
REFERENCES 130
BIOGRAPHICALSKETCH 141
V
AbstractofDissertationPresentedtotheGraduateSchool
oftheUniversityofFloridainPartialFulfillmentofthe
RequirementsfortheDegreeof
DoctorofPhilosophy
PHYSIOLOGICALANDSENSORYASPECTSOFMATURATION,RIPENING,
ANDPOSTHARVESTCHILLINGOFFRESHMARKETMELTING-AND
NONMELTING-FLESHPEACHFRUIT
By
ErnestoA.Brovelli
May1997
Chairman;Dr.JeffreyK.Brecht
Cochairman:Dr.WayneB.Sherman
MajorDepartment:HorticulturalScience
A studywasconductedtodetectdifferencesinsensoryandchemical
characteristicsofmelting-(MF)andnonmelting-flesh(NMF)peachgenotypesintended
forthefreshmarket.SensoryresultsshowedthattheNMFfhiit(‘OroA’andFL86-28C)
wereratedas“harder,”less“juicy,”andmore“rubbery”thantheirMF(FL90-20and
‘TropicBeauty’)counterparts. Aprincipalcomponentanalysisofthesensorydatashowed
acleardistinctionbetweenthetexturalaspectsofMFandNMFfruit,butnotbetween
theirflavoraspects.Likewise,chemicalanalysisshowedthatwhiledifferencesinpH,
titratableacidity,andsolublesolidsweredetectedamongthefourgenotypes,no
consistentgroupingcouldbemadebasedontheMF/NMFnatureofthe fruit.
VI
Individuallinearcorrelationswereconductedbetweeneachgenotype’sfruit
attributesatharvestandtheirrespectivesensoryfirstprincipalcomponents(PCIs)after
storageandripening. FollowingarethethreeattributesthatbestcorrelatedwithPCI,and
thus,theyarethemostpromisingmaturityindices;forFL90-20.groundcolor(GC)hue,
GCL,andcheek(CH)texture;for‘TropicBeauty’:peelL,CHtexture,andblossom-end
(BE)texture;for‘OroA’:CHtexture,BEtexture,andCHchroma;for86-28C:BE
texture,CHhue,andCHtexture. BEandCHtexturewerehighlycorrelatedwithPCIsin
bothMFandNMFgenotypes,thushighlightingtextureasapotentialmaturityindex.
AstudytocomparetheresponsetopostharvestchillingofMF(FL90-20,FL90-
21,andFL91-16)andNMF(‘OroA’,FL90-35C,andFL90-47C)genotypesrevealed
thatwhileallMFgenotypesdevelopedsymptomsofmealinessin1or2weeks,theNMF
genotypesdidnotshowthisdisorder. MealinessintheMFgenotypeswasapparently
relatedtoanincreaseincellseparation. Histologically,chillingofMFfruitbroughtabout
animpressiveexpansionoftheintercellularspacesinmesocarptissue,butdidnotaffect
NMFfruit. SensoryevaluationtoassesschillinginjuryshowedthatwhilechilledMFfruit
werescoredassignificantlymore“mealy,”less“sweet,”andwithless“peachcharacter”
thannon-chilledfinait,nomajordifferencesinthosenotesoccurredbetweenchilledand
non-chilledNMFfruit. Ontheotherhand,chilledfhiitofbothMFandNMFtypeswere
scoredassignificantlyless“juicy”and“harder”thannon-chilledfruit. Ananalysisof
aromavolatilesrevealedthatthemostrelevantchangesoccurringinbothMFandNMF
fruitwithchillingwereanincreasein(E)-2-hexenalandadecreaseinthelevelsofy-and
5-decalactones.However,theextentofthedropinbothdecalactoneswassignificantly
lessinNMFthanMFfhiit.
vii
CHAPTER
1
INTRODUCTION
Pnmusgermplasmisvariedandconsistsofnumerousspeciesandtypeswithinthe
species. Theheterogeneousgeneticbaseofthepeach—PrM/n/5persica(L.)—isdisplayed
inthegreatphenotypicvariabilityexhibitedbythefhjit. Accordingto appearanceand
sensorycharacteristics,peachfruitcanbeclassifiedasround,flatorbeaked;pubescentor
smooth-skinned;freestoneorclingstone;white,yellowor redfleshed;sweet,souror
astringent;andmelting-(MF)ornonmelting-fleshed(NMF)(Rom,1988).
ThemaindistinctionbetweenMFandNMFfruitisthatthelatterlacktherapid
lossoffirmness,knownas“meltingofthefruit,”characteristicofthefinalstagesof
ripeningofMFfruit(Lesteretal.,1996). Basedonthisdistinction,fruitofthesetwo
typeshavetraditionallybeenchanneledtoeitherthefreshmarket(MF)orthecanning
industry(NMF).
WhenMFpeachesarelefttoripenonthetreeinordertoachievemaximum
quality,theyshowapropensitytomechanicaldamageanddecayduringshippingand
handling,thatresultsinareducedpostharvestlife(Robertsonetal.,1992a). UnlikeMF
peaches,NMFcultivarsaretraditionallygrownforcanningpurposesduetotheSuit’s
tolerancetothehigh-temperatureretorttreatment,whichcancompromisefruitintegrity
TheseNMFcultivars,however,lacktheredcoloration,acidity,andaromaofcommonly
growndessert-typeMFfhjit.
1
2
Animportantgoalforcurrentbreedingprogramsis todevelopNMFpeaches,but
withfresh-marketsensory characteristics. Thepurposeistodevelopfruitthatareableto
attainmaximumflavoronthetree,yetmaintainsufficientfirmnesstoallowdistribution
throughnormalmarketingchannels(Shermanetal.,1990).
WhilesensorychangesoccurringduringripeningofMFpeacheshavebeen
thoroughlystudied(DelwicheandBaumgardner,1983;Chapmanetal.,1991,Robertson
etal.,1992b),NMFfruitintendedforthefreshmarkethavenotreceivedthesame
attention.Similarly,nomaturityindiceshavebeenidentifiedforthesenewerNMF
genotypes.Theearlyblushingandslow-softeningcharacteristicofsomeofthesenewer
genotypesposesthequestionofwhetherground-colororfirmnessmeasurements,two
commonsindicatorsofmaturityforMFpeaches,canhaveanypredictivevalueofthe
NMFfruit’sfinalqualityassessment.
Eventhoughthesenewergenotypesmayeffectivelyaddresstheproblemof
excessivesofteningandmechanicaldamage,theirsuitabilityforlow-temperaturestorage
remainsunknown. Althoughrefrigerationisconsideredanindispensableneedfor
minimizingphysiologicaldeterioration,decay,andmoisturelossinpeaches,low-
temperaturestorageisassociatedwithaseriousphysiologicaldisorderknownasinternal
breakdownorchillinginjury(Ben-Arieetal.,1970;Anderson,1975).Basedonthe
detrimentalimpactthatthisdisorderishavingonthefreshmarketpeachindustry(Bruhn,
1994;Stockwin,1996),itiscriticaltoassessthetolerancethatthesenewergenotypes
havetochillinginjury.
CHAPTER2
LITERATUREREVIEW
Introduction
Thepeach,Pntnuspersica(L.)Batsch, isthoughttohaveoriginatedinChina,in
anareanearthecityofXian. Thespeciespersicaisbutoneofabout250specieswithin
thegenusPnmus(Rom,1988a). Thesmooth-skinnednectarinealsobelongstothis
species,buthasbeencategorizedunderthevarietynamenectarina(LaRue,1989)
Thepeachiswidelydistributedbetweenthe30°-40°latitudes(Rom,1988a)andis
successfullygrownintheUnitedStates,withatotalharvestedareaof71,012hectaresin
1993. Theproductionvolumeforthatyearreached1206millionkg,withapproximately
halfofthisvolumeaimedforfreshconsumptionandhalfforprocessing(USDA,1994).
FruitDevelopment
Thepeachfruitoriginatesfromaperfect(i.e.withbothsexespresent)and
complete(i.e. havingcalyx,corolla,androeciumandgynoecium)flower. Following
pollinationandfertilization,theperianthisshedandtheovarycontinuestoenlarge. The
fruitletdevelopsintoadrupe,withathinepicarp,afleshymesocarpandastonyendocarp
containingtheseed(Rom,1988b). Thepeach,aswellasotherdrupes,showsa double-
sigmoidgrowthcurve,withthreedistinctphasesofgrowth:(I)celldivisionand
expansion,(II)slowgrowthandlignificationoftheendocarp,and(III)cellexpansionin
themesocarptissue(Connors,1919). AlthoughMasiaetal.(1992)acknowledgethe
3