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*eshr.olotrY r anl rslrl'1't- $.vitr onl va1et.\\cs ' 56jcnce, lan, FL Section 3d ) aualitYParameters
of Fresh-cut Products
Textural(Feel) Quality Factors
Flavor (Eating)QualityFactors"""""""' 13
Maturity and Ripening....
........physicalDamageDuring Harvestingand Handling
and RelativeHumidity Management
Applied to the Commodity
of the Environment......-""' l8
Life of Fresh-cut
Flavor vs. Appearance
References.... of attributes,prop
Quality of fresh-cutfruit and vegetableproductsis a combination
erties,or characteristics determinetheir valueto the consumerQuality parameters
texture,flavor, and nutritive value.The relativeimportanceof each
quality p*u*.ter depends
upon the commodity or the productand whetherit is eaten
and dips) or cooked-Confresh (with or without flavor modifiers, such as dressings
judge quality of fresh-cutfruits and vegetables the basis of appearance
sumers l -5E7 G03G7/02$0.0O+$
e 2m2 by CRC hess LLC 1l 12 Science,Technology, and Market
Fresh-cutFruits and Vegetables: Section 3d pur("best if usedby" date)at the time of purchase.
in termsof texruraland flavor(eating)
Consumers alsointerested the nutritional
Qualityof the intactfruit or vegetable
maturiryat harvest, harvesting
also havemajor impactson qualityof intactfruits andvegetables
productsAdditionalfactorsthat influencequality of fresh-cut
quality of the fresh-cut
(sharpness the cutting tools,
include method of preparation
fruits and vegetables
areaof the cut pieces,washing,and removal of surfacemoisture)
size and surface
mum rangesof temperature
program must takeinto conAn
procedures). effectivequality assurance
siderationall the factorsthat affectquality of the intact fruits or vegetables their
fresh-cutproducts. QUALITY PARAMETERS
These may include size, shape,color, gloss,and freedom from defectsand decay.
Defectscan originatebefore harvestas a resultof damageby insects,diseases,
(such as scars,scabs,
and hail; chemicalinjuries; and variousblemishes
defectsmay be morphological,
garlic; rooting of onions; elongationand curvatureof asparagus;
presence seedstems cabbage
fruits suchaslemons,tomatoes, peppers;
and lettuce; doublesin cherries; and floret opening in broccoli- Physicaldefects
internal drying of somefruits;
include shrivelingand wilting of all commodities;
such as punctures,
and bruising; and growth
and scuffing, deformation(compression),
breakdown of stone fruits, water core of apples,and black heart of
Examplesof defectsthat do not influencepostharvest potentialof freshproduce
include healed frost damage,scars,and scabs;well-healedinsect stings;irregular
shape;and suboptimalcolor uniformity andintensity.
reducepostharvest potential of fresh fruits and vegetables.
Tissuebrowning,which can be a major defectof fresh-cutfruits and vegetables,
dependsupon the concentration phenoliccompounds,the activity of polyphenol
oxidase(PPO), and the concentration antioxidants the tissue-Wound-induced
(mainly in the
loss of cellularcompartmentation
browning at a ratethatincreases
vacuole)and PPO (in the cytoplasm)resultsin tissue
with temperature water stress.
Q u a l i t y P a r a m e t e r s f F r e s h - c u F r u i t a n d V e g e t a b l eP r o d u c t s Section 1 3
Texruralqualiryof fruits and vegetables not only important their eating
andcookingquality but alsofor tlreir shippingabiliry.Soft fruits cannot shippedlong
harvestlosses to physicalinjuries.This hasnecessitated
ing fruits at less than ideal maturity from the flavor qualiry shndpointin many cases,
suchas the melonssold during the winter monthsin the U.S. markets.
loss of integrity and leakageof juice from some
fresh-cutproducts can be the primary causeof poor quality and unmarketability.
calciumconcentration the tissue
can slow down its softening
initial firmness,temperature, vibration influencethe rate of softeningand juice
leakagefrom fresh-cutfruits. Fmvon(EnnNc)
flavors.Flavor quality involves perceptionof the tastesand aromasof many compounds.Objective analyticaldetermination critical components
must be coupled
evaluations a taste
panelto yield usefuland meaningful
quality of freshfruits and vegetables.
This approach be usedto define
a minimum level of acceptability. find out consumerpreferences flavor of a given
testing a representative
sampleof the consumers required.
Flavorquality of mostfruits is influencedby their contents sugars
(aroma).More information is neededabout the optimum concentration
and develkind of fruit (to satisfy the majority of consumers).
Also, future research
segregation fruits on the basisof their contentsof sugars,
volatiles.In many cases,
consumers willing to pay a higher price
for fruits with good flavor,and thereis a growing trend of high-quality-based
that servethis clientele. Nurnrnor.rnl
Fresh fruits and vegetables
play a significant role in human nutrition, especially as
(vitamin C, vitamin A, vitamin Bu, thiamine,niacin),minerals,and
dietary fiber. Other constituents
that may lower the risk of cancer,
polyphenols,and other phytonutrients.
lossesin nutritionalquality,particularlyvitamin C content,
can be substantial andareenhanced physicaldamage,
low relativehumidiry, and chilling injury of chilling-sensitive
Nutritionalvalue variesgreatlyamongcommoditiesand cultivars eachcomof
modity. By using plant breedingand biotechnologyapproaches, is possible to
quality and improvedflavor quality to
consumers eatmorefruits and vegetables leastfive servingsper day).
to 14 ,
F r e s h - c u tF r u i t sa n d V e g e t a b l e s :S c i e n c e T e c h n o lo g y , a n d M a r k e t Section
This can have a major positiveimpact on human healthand shouldbe given high 3d
priority in research
PREHARVEST ACTORS INFLUENCING QUALITY
Witlin eachcommodity,thereis a range of genorypicvariationin composition,
life potential.Plant breedershave been successful selectingcarrot
and tomato cultivarswith much higher carotenoidsand vitamin A content,sweetcorn
longer after haryest,cantaloupe
cultivars that maintain their sweetness
higher sugar contentand firmer flesh, and pineapplecultivarswith higher contentsof
These arejust a few examples what has been
ascorbicacid, carotenoids, sugars.
accomplishedin improving quality of fruits and vegetables
cultivars, selected their ability to wittrstand
However, in some cases,
marketinganddistribution,tend to lack sufficient
Rootstocks used in fiuit production vary in their water and nutrient uptake
abilitiesand in resistance pestsand diseases.
compositionand somequality attributesas well as yield, in many casesThere are many opportunitiesin using biotechnologyto maintain postharvest
quality and safety of fresh-cutproducts- However, the priority goals should be to
ieduce browning potentialand softeningrate, to attainand maintain good flavor and
resistance physand to introduce
nutritionalquality to meetconsumer
pathogens reducethe use of chemicalsand/ordecay-causing
to determinepriorities for geneticimprovementprograms.
the consumption of certain commodities and/or cultivarsthat are alreadyhigh in
than breedingfor higher
nutritive value may be more effective and less expensive
have a stronginfluence
and light intensity,
on compositionand nutritionalquality of fruits and vegetables.
location and seasonin which plants are grown can determinetheir ascorbicacid,
and flavonoidscontent. general, lower the light
intensity, lower the ascorbic
uptakeand metabolism mineralnutrientsby plantsbecause
to the plant, which may
Rainfall affects the water supply
with higher temperatures.
plant part and its susceptibility mechanical
of the harvested
harvestingand handling operations.
Soil type, the rootstockused for fruit trees,mulching,irrigation,and fertilization
influence the water and nutrientsupply to the plant, which can affect the nutritional
plant parl. The effect of fertilizerson.the vitamin contentof
quality of the harvested o
Q u a l i t y P a r a m e t e r s f F r e s h - c u F r u i ta n d v e g e t a b l e P r o d u c t s 15 Section 3d plantsis less importantthan the effectsof genotypeand climaticconditions,but their
influenceon rnineralcontentis more significant.For example,
sulfur and selenium
uptakeinfluencethe concentrations organosulfur
compounds Allium andBrassica
High calciumcontentin fruits has beenrelatedto longerpostharvest as
a result of reducedrates of respirationand ethyleneproduction,delayedripening,
increasedfirmness,and reducedincidenceof physiologicaldisordersand decay.In
contrast,high nitrogen contentis often associated
supply to citrustreesresultsin somewhat
lower acidity and ascorbicacid contentin citrus fruits, while increased
their acidity and ascorbicacid content.
For example,bitter pit of apples;blossom-endrot of tomatoes,
melons;cork spot in applesand pears;and red blotch of lemonsare associated
calcium deficiency in thesefruits. Boron deficiency resultsin corking of apples,'
apricots,and pears; lumpy rind of citrus fruits; malformationof stone fruits; and
cracking of apricots.Poor color of stone fruits may be relatedto iron and lor zinc
Excesssodiumand/orchloride (due to salinity)resultsin reduced
size and higher solublesolidscontent.
Severewater stressresultsin increasedsunburnof fruits, irregular ripening of
pears,and tough and leatherytextureof peaches.
contents solublesolids,acidity,and ascorbic
acid.On the other
hand,excesswater supplyto the plantsresultsin crackingof fruits (suchas cherries,
turgidity leadingto increased
susceptibility physical damage,
suchaspruningand thinningdetermine crop load andfruit
size, which can influencecompositionof fruit. The use of pesticides
regulatorsdoes not directly influencefruit compositionbut may indirectly affect it
due to delayed or accelerated
fruit maturity. MATURITY ND RIPENING
Maturationis the stageof development
leading to the attainment physiological
maturity is the stageof development
a plant or plant part will continue
is the stageof development
when a plant or plant part possesses prerequisites
utilization by consumers a particular purpose.
Maturity at harvestis the most important factor that determines
final fruit quality. Immaturefruits are more subjectto shrivelingand mechanical
damageand are of inferior quality when ripe. Overripe fruits are likely to become
soft and mealy with insipid flavor soon after harvest.Any jruit picked either too
early or too late in its season more susceptible physiological
a shorterstoragelife than fruit picked at the proper maturity. 16 F r e s h - c u tF r u i t s a n d V e g e t a b l e s S c i e n c e , e c h n o l o g y ,a n d M a r k e t
All fruits and mature-fruit vegetables,
with a few exceptions(such as European3d
reachtheir besteatingquality when allowedto ripen
on the tree or plant. However, some fruits are usually picked mature but unripe so
that they canwithstand postharvest
when shippedlong distance.
Most currentlyusedmaturity indicesarebasedon a compromisebetweenthoseindices
that would ensure best eating quality to the consumerand thosethat providethe
neededflexibility in marketing.
For most non-fruit- and immafure-fruit-vegetables
squash,sweetcorn, green beans,and sweetpeas),the optimum eatingquality is
reachedbeforefull maturity. In thesevegetables, problem frequentlyis delayed
harvest,which resultsin lower quality at harvest
Ripening is thecomposite the processes occurfrom the latter stages growth
through the early stagesof senescence that resultsin characand
and/or food quality,as evidenced changes composition,
texture, or other sensoryattributes.
Fruits can be divided into two groups:fruits that are not capableof continuing
their ripening processonce removed from the plant and fruits that can be harvested
mature and ripenedoff the plant. The following are examplesfrom eachgroup:
citrus (grapefruit,lemon, lime, orange,mandarin,and tangerine),grape,
tamarillo, and watermelon.
' Group two includes apple, pear, quince, persimmon, apricot, nectarine,
plum, kiwifruit, avocado,
sapoguava,passionfruit, and tomato.
Fruits of the first group, with the exception of some types of muskmelons,
producevery small quantitiesof ethyleneand do not respondto ethylenetreatment
exceptin termsof degreening
(removalof chlorophyll);theseshouldbe pickedwhen
fully ripe to ensuregood flavor quality. Fruits in group two produce much larger
quantitiesof ethylenein associationwith their ripening, and exposureto erhylene
treatment(100 ppm for I to 2 days at 20"C) rvill result in faster and more uniform
ripening. Once fruits are ripened, they require more careful handling to minimize
bruising. Fruits in group two must be ripened,at least partially, before cutting to
assurebetterflavor quality in the fresh-cutproducts- POSTHARVEST
DuRtNc HARVESnNG Hnruouxc
Harvestingmethodcan determinethe extentof variability in maturity and physical
and quality of fruits andvegetables.
cuts,etc.)can accelerate of water
Quality Parameters f Fresh-cut ruitand Vegetable roducts 17 Section 3d pathogens. incidence
and vitaminC and increase
and severityof such injuries are influencedby the method of harvest(hand vsand handlingoperations.
and management the harvesting
before,during,and aftercuttingis a major contributor tissue
and fasterdeterioration the fresh-cutproducts.
browning, juice leakage,
AND Rnnrrvr Humtotrv MnTAGrMENT
within their optimal rangesof
Keeping intact and fresh-cutfruits and vegetables
temperature relativehumidity is the most importantfactor in maintaining
point (for non-chillingquality and minimizingpostharvest
sensitive commodities)and above the minimum safe temperature(for chillingdeterioration
every l0"C increase temperature
quality by two- to threefold.Delays betweenharand the rate of loss in nutritional
vestingand coolingor processing resultin quantitative
(losses flavorandnutritionalquality)-The extent
upon the commodity'sconditionat harvestand its temperdepends
ature, which can be severaldegreeshigher than ambienttemperatures,
when exposed directsunlight.
chainrarelyhasthe facilitiesto storeeachcommodityunderideal
conditionsand requireshandlersto make compromises to the choicesof temperand loss
ature and relativehumidity.Thesechoicescan leadto physiological
of shelf life and quality.The weakesttwo links in the postharvest
chain of fresh fruits and vegetables the retail and home handlingsystems.
AppuEDTo rHE CoMMoDtw
cleaning,sorting to eliminatedefects,
These include curing of "root" vegetables,
with fungicides decay
control, heat treatingfor decay and/or insectcontrol,fumigating for insectcontrol,
sproutingor insectdisinfestation, exposingfruits to
ethylene for faster and more uniform ripening.In most cases,thesetreatments
postharvest of the produce.
period that can be usedfor each
there is a needto determinethe maximum storage
commodity betweenharvestand preparationas a fresh-cutproduct. Generally,the
longer the storagedurationof the intact commoditybetweenharvestand cutting,
the shorterthe post-cutting of the products.
modificationvary greatlyamongplant species,
stage,and duration and temperature exposure.
the optimal rangesof oxygen, carbon dioxide, and ethyleneconcentrations
the commodity extends postharvest by about50-l08Vo relativeto air control.
and lossesof ascorbicacid in
In general,low O, atmospheres
CO2atmospheres b lAVo lB T
F r e s h - c u tF r u i t sa n d V e g e t a b l e s : c i e n c e , e c h n o l o g y ,a n d M a r k e t Section 3d On
theselosses. the otherhand,COrcan
but higherCO, concentrations accelerate
in delayingbrowning and microbialgrowth
enrichedatmospheres be beneficial
fruits and vegetablesfresh-cut
Exposureto ethylenecan be detrimentalto the quality of most vegetables
commodities from ethyleneshould be avoidedby separatingethylene-producing
and/or by introducingfresh,
sensitivecommodities, using ethylenescrubbers,
rooms.Treatingthe fruits and vegetables their freshair
ethylene-free into storage
cut productswith 0.5-l ppm 1-methylcyclopropene about six hours protects
Fuvon vS. AppEARANCE or Fnrsu-cur FRUII PnOoucrs
Even under optimum preparationand handling conditions,postcuttinglife basedon
More research neededto identify the
flavor is shorterthanthat basedon appearance.
to slow it down and to restorethe
reasonsfor the flavor loss and possiblefieatments
ability of the fruit tissueto producethe desirableestersand other aromacompounds.
Use of calciumchloride or calcium lactatein combinationwith ascorbicacid and
cysteineasa processing (two-minutedip) hasbeenshownto be effectivein firmness
in delayingbrowning of fresh-cutfruits.Ethylenescrubbingandmodified
packaging(to maintain 2-5Vo OTand 8-127o CO) can be useful suppleatmosphere
management maintainingquality of fresh-cutfnrit prodrnentsto good temperafure
ucts.Additionalresearch neededto optimizepreparation
of eachfruit productfor
procedures maintainingquality and safety PROCRAMS
An effectivequality assurance
good-qualitysupplyof freshand retail displayis requiredto provide a consistent
and to protect the reputationof a given
cut fruits and vegetables the consumers
startsin the field with the selectionof the proper
time to harvestfor maximum quality. Careful harvestingis essentialto minimtze
step after harvesthas the
physical injuries and maintain quality. Each subsequent
potentialto eithermaintain or reducequality; few postharvest
the quality of individual units of the commodityrelative humidities, and/or concenExposureof a commodity to temperatures,
trations of oxygen,carbon dioxide, and ethyleneoutside its optimum rangeswill
The loss of flavor and nutritionalquality of
accelerate of utt quality attributes.
occursat a fasterrate than the lossof textural
fresh intactor cut fruits and vegetables
programsshould be basedon all
qualities.Thus, quality assurance
factorsas is often the case.
quality attributes, only on appearance
Followingis a list of handlingsteps
l. Trainingworkerson propermaturityandquality selection,
and produceprotectionfrom sun exposureduring harvestingoperations
upon arrival at the
2. Checkingproduct maturity, quality, and temperature
Q u a l i t y P a r a m e t e r s f F r e s h - c u F r u i t a n d V e g e t a b l eP r o d u c t s 19 3. Implementingan effectivesanitationprogramto reducemicrobial load
and shippingcontainers ensure
5. Training workerson properprocessing
6. Inspectinga randomsampleof the packedproductto ensurethat it meets
completion the cooling proto
7 . Monitoring producttemperature assure . cessbefore shipment
8. Inspecting transport
9. Training workerson properloading and placement temperature-recordin eachload
10. Keeping recordsof all shipmentsas part of the
I l. Checkingproductquality upon receiptand moving it quickly to the appropriate storagearea
12. Shippingproductfrom distributioncenterto retail marketswithout delay
basisunlessits conditionnecessitates different
and on a first-in/first-out
Beaudry,R.M. 1999.Effect of O, and CO2 partial pressure selected
quality.Posthart. Biol. Technol.15:293-303.
fruits and vegetables.
Brecht, J.K. 1995. Physiologyof lightly processed
Ferguson, Volz,R., andWoolf,A. 1999.Preharvest
of fruit. Postharv.
Goldman,I.L., Kader,A-A., and Heinlz, C. 1999.Influence production,handling,and
PostharvestTechnology Horticultural Crops,secondedition.Publ.
Kader,A.A. (ed.). 1992.
CA, 296 ppOakland,
331l, Univ. Calif.,Div. Agr. Nat. Resources,
Kader,A.A. 1999.Fruit maturity,ripening,and quality relationships.
Lee, S.K. and Kader,A.A. 2000.Preharvest
contentof horticulturalcrops.Postharv.Biol- Technol.
factorsinfluencingflavor of freshfruits and
chnol. | 5:227
vegetable Postharv.B iol. Te
and relativehumidity on fresh commodityquality.
Paull, R.E. 1999.Effect of temperature
Postharv. iol. Technol.
Hortfruits and vegetables.
Romig, W.R. 1995. Selection cultivars for lightly processed
PostharvSalrveit,M.E. 1999.Effect of ethyleneon quality of fresh fruits and vegetables.
B iol. Technol.| 5:279-292.
texture.Posthan BioI. Technol.
factors affecting postharvest
Sams, C.E. 1999. Preharvest
Shewfelt,R.L. and Brtickner, (eds.).
Publ.Co., Lancaster, 330 pp. Section 3d 2A Fresh-cutFruits and Vegetables:Science,Technology,and Market Section
A-E., Ko, N.P-,and Minott, D.A. 1996.Factorsaffectingquality of fresh-cuthortiWatada,
Watada,A.E. unO Qi, L. 1999. Quality of fresh-cut produce. Postharv-Biol- Technol15:201-205.
factors affecting postharvest
Weston,L.A. and Barth, M.M. l9g-7.Preharvest
svegetable H ortscience. 32:812-816
RefrigeratedFruits andVegetables(ed.). lgg4. Minimally Processed
Chapman& Hall, 368 PP- 3d ...
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This note was uploaded on 05/03/2009 for the course FST 160 taught by Professor Giovanni during the Spring '08 term at UC Davis.
- Spring '08