J. Appl. Hort., 2(2):71-75, July-December, 2000
Postharvest disinfestation of mango (Mangifera indica cv. Manila)
with controlled atmospheres
Dinora M. León1, Dora A. Ortega2, Héctor Cabrera2, Javier De La Cruz1, Kirk L. Parkin3 and
Hugo S. Garcia1*
1
UNIDA, Instituto Tecnológico de Veracruz, Apdo. Postal 1420, Veracruz, Ver. 91860, México. Phone/Fax 01(2) 9345701. 2 Campo Experimental Cotaxtla, CIRGOC-INIFAP, SAGAR, México 3Dept. of Food Science, University of Wisconsin-Madison, Babcock Hall, Madison, WI 53706, USA.*Responsible author to whom all correspondence should be addressed. Email: hsgarcia@itver.edu.mx
Abstract
Manila mangoes were infested in the tree by allowing fertile Anastrepha obliqua female flies for oviposition on fruits contained inside
cages. Infested mangoes were exposed to nine different controlled atmospheres (CA) containing combinations of 1, 3 or 5% O2 and
30, 50 or 70% CO2. Surviving larvae were enumerated after subjecting the mangoes to the CA for periods of 1 to 5 days. Selected
compositional and physical parameters (weight loss, pH, titratable acidity, colour, soluble solids, reducing sugars and texture) were
analyzed during post-treatment ripening. Fully ripened fruits were also subject to sensory evaluation using a non-structured hedonic
scale and a trained panel. CA containing 1% O2 and either 30% or 50% CO2, effectively killed all the larvae present in treated fruits.
These treatments did not alter the composition or sensory characteristics of fully ripened mangoes. However, losses of 20 to 25% of
fruits on the basis of sensory acceptability were attributed to the development of “spongy” tissue. CA’s containing 70% CO2 were also
effective in disinfestation, but also affected compositional and sensory qualities of the fruits, and induced the “spongy” texture defect
in 65% of the fruits.
Key words: Controlled atmosphere, disinfestation, mango, Anastrepha obliqua, larvae, post-treatment ripening, sensory evaluation,
disinfestation, texture
Introduction
Mexican mangoes of the Florida varieties (Kent, Keitt, Haden
and Tommy Atkins) are regularly exported to the U.S. market at
annual rate of over 100,000 tons. However the Manila variety,
the one with the highest production in Mexico is only starting to
get attention from the producers as a variety with potential for
export. The main problem to solve for any exported variety is
disinfestation of the mangoes from fruit fly larvae (Anastrepha
sp.). Some of the alternatives for insect control are insecticide
application, refrigerated storage (Hatton, 1991; Mitchell and
Kader, 1992), irradiation (Windeguth, 1986; Mitchell and Kader,
1992; Toledo et al., 1992), and hot humid air (Balock and Starr,
1945; Heard et al., 1992). These treatments have not been entirely
innocuous or injury-proof for the fruits. Some of their
disadvantages are: possible carcinogenic residues (Coates et al.,
1993), chilling injury, possible sterile larvae survival and spongy
tissue. Since 1988, hydrothermal treatment is the only USDAapproved process for control of anthracnose and fruit fly
disinfestation of mangoes destined for the U.S. market
(Celedonio-Hurtado, 1992; Mitchell and Kader, 1992).
Application of the procedure has resulted in several limitations,
such as advanced ripening, weight reduction (Jagtiani et al.,
1988), necrosis of defined areas in mangoes of small size
(McIntyre et al., 1993), pitting in peduncular area (Rojas, 1993),
scalding and off-flavours development as well as practical
problems at large-scale packing plants (Celedonio-Hurtado,
1992).
The use of controlled atmospheres (CA) is a viable option for
larval control at different maturity stages by exposing fruit to
atmospheres containing low O2 and high CO2 concentrations
for short times (Brandl et al., 1983; Soderstrom and Brandl, 1984,
1985; Lidster et al., 1981, 1984; Jay, 1984; Benschoter, 1987;
Soderstrom et al., 1986, 1990; Yahia, 1998). Recent reports have
indicated that exposure of Keitt mangoes to short periods of
insecticidal CA did not affect normal ripening or sensory
attributes of the fruits (Yahia and Vazquez-Moreno, 1992; Yahia,
1993; Yahia and Tiznado-Hernandez, 1993). These treatments
were not tested on mangoes of the Manila variety. In this study
we subjected Manila mangoes to CA with high CO2 and low O2
to evaluate their disinfestant ability. CA could be an alternative
to hydrothermal treatment.
Materials and methods
Larval infestation. Manila mangoes were infested in the
production fields of Cotaxtla Agricultural Experiment Station
(INIFAP) with fertile Anastrepha obliqua flies grown on
laboratory diets. An average of 10 fruits in the tree were placed
inside plastic mesh cages and 30 fertile female and 10 male flies
were introduced. Oviposition was allowed to proceed and fruits
were harvested after 8 days, to insure that larvae were in the
third stage of growth inside the fruit.
Disinfestant treatment. Preclimacteric infested mangoes were
washed with a 0.1 g/l Benlate® (E.I. DuPONT de Nemours &
Co. Inc.) solution. Fruits were sorted randomly and divided into
72
Journal of Applied Horticulture
lots. One lot was used as control and set to ripen at 25 °C with
no CA treatment. The other lots were differentially treated in a
complete 3 x 3 design to CA with compositions of 1, 3 and 5%
O2 and 30, 50 and 70% CO2 . Certified gas mixtures were
purchased from AGA gas. Twenty fruits were withdrawn at each
sampling period and allowed to ripen at 25 °C for up to 12 days.
Mangoes were exposed to CA for periods of 1 to 5 days at 25 °C
in 0.45 m3 fiberglass chambers. Gas flow was 235 ml/min and
humidified passing it through water before entering the chamber.
At the end of the ripening period, mangoes were dissected for
the purpose of counting larvae (dead or alive) and fruit damage
was assessed visually. Efficacy of disinfestation was expressed
as percentage of dead larvae found.
Analyses: Three mangoes were used for analysis at each
treatment interval for each CA treatment. Physiological weight
loss was measured by direct weighing. Textural hardness was
measured with a fruit penetrometer fitted with a 6 mm conical
probe and a gauge of 0-12 kg force. Colour reflectance changes
in excised slices of the mesocarp were followed with a Minolta
CR-200 colorimeter using the CIE L*a*b scale. Mesocarp
homogenates were employed to measure pH and titratable acidity
by direct titration with 0.1 N NaOH. Soluble solids were
monitored with a desktop Abbe refractometer, and reducing
sugars with the 3,5 dinitrosalicylic acid procedure (Miller, 1959).
Sensory Evaluation: An hedonic test with a non-structured scale
and 10 trained panelists was used to grade attributes of aroma,
off-flavor, visual colour, sweetness, tartness and overall
acceptance.
Statistical Analysis: Linear regression analysis was used to
evaluate the relationship between time of exposure and the
treatments. Physico-chemical as well as sensory evaluation data
were analyzed by ANOVA and Tukey’s paired comparison test
(α = 0.05), employing the statistical software package MINITAB
v. 10.1.
Results and discussion
The level of initial infestation obtained was 85 insects per 20
mangoes. Complete larvae mortality was achieved within three
days of treatment for CA of 1% O2 and either 30 or 70% CO2
(see Table 1). The CA containing 1% O2 and 50% CO2 required
5 days of treatment before 100% mortality was observed.
According to the USDA, any treatment that could be considered
for approval must assure a mortality of 99.99% of fly larvae and
eggs (Landolt et al., 1984). Based on that premise, the treatments
used in this study fulfill that criterion.
The interrelationships between CA parameters and larvae
mortality were modeled by linear regression analysis, which
generated the following equation:
Log10 Y = 0.913 - 0.426X1 + 0.594X2 - 0.861X3 - 0.168X1X2
+ 0.237X1X3 + 0.583X2X3 - 0.802X1X1 - 0.211X2X2
- 0.117X1X2X3
where X1 is the % of CO2, X2 is the %O2 in the CA, and X3 is
the number of days of exposure. The analysis indicated that the
statistically significant factors which affected larvae mortality
were the main effects of % O2, % CO2, days of exposure, and
the interaction between % O2 and days of exposure. The
interactions between %O2 and %CO2 or days of exposure, as
well as the multiple interaction between the same variables were
not significant. It was clear that greater larvae death rates were
obtained at lower O2 concentrations (Fig. 1). The statistical model
was not adequate to explain the trends of CA containing 70%
CO2 (Fig. 2), since some treatments achieved 100% larvae
mortality within the first day of exposure. This fact reduced the
correlation coefficient (r2) to 0.62.
Table 1. Percentage mortality of Anastrepha obliqua larvae in
Manila mangoes subjected to controlled atmospheres at 25 °C
%
CO2
30
O2
1
3
5
1
3
5
1
3
5
50
70
1
67
76
30
73
69
65
72
100
80
2
35
88
62
90
57
75
95
99
93
Days
3
100
88
85
99
98
93
100
100
95
4
100
94
92
99
88
98
100
95
100
5
100
98
94
100
96
98
100
97
96
Table 2. Spoilage observed in treated mangoes, expressed as
percentage of fruits with injury symptoms, mainly internal
breakdown
Days
CO2 (%)
O2 (%)
Spoilage(%)
3
4
5
3
4
5
3
4
5
30
30
30
50
50
50
70
70
70
1
1
1
1
1
1
1
1
1
25
55
70
20
45
55
60
65
75
Colour of the mesocarp in treated fruits did not show any change
during the first three days and exhibited lesser colour
development compared to control mangoes (Fig. 3). It has been
proposed that CA may inhibit chlorophyll degradation and
carotenoid synthesis (Weichmann, 1986). Reducing sugars in
mango juice was not affected by the treatments (Fig. 4). The
rather constant levels of reducing sugars suggests that ripening
was delayed because of the exposure to the CA, instead of
increasing, which is consistent with the report of Krishnamurthy
and Subramanyam (1973).
Treated mangoes lost less weight than control fruit probably due
to the humidification of the CA during treatment, (Fig. 5).
Relative humidity inside the chamber was ca. 90%, compared
to 70-72% outside, this is likely responsible for the CA treated
mangoes suffering less shrinkage, lack of juiciness and fewer
overall appearance defects as compared to control fruit as
previously found by Kader (1986).
The pattern of soluble solids changes in mangoes treated with
1% O2 and either 30 or 50% CO2 were not different from the
control fruits during the five days of CA exposure (Fig. 6).
However, CA containing 70% CO 2 produced statistical
Postharvest disinfestation of mango with controlled atmospheres
12
1
1%
3%
5%
0.1
0.01
0.001
1
8
6
4
2
Fig. 1
0
Fig. 5
Control
1%
3%
5%
10
10
% Weight loss
Surviving larvae
100
73
2
3
4
5
0
6
0
1
2
3
4
5
6
5
6
100
1%
3%
5%
Surviving larvae
10
1
0.1
0.01
Fig. 6
Fig. 2
0.001
0
1
2
3
4
5
6
5
Control
30%
50%
70%
92
4.5
88
4
Fig. 7
pH
Hue
96
84
3.5
80
1%
3%
5%
Control
76
Fig. 3
72
0
1
2
3
3
2.5
4
5
6
0
1
2
3
4
Fig. 8
Fig. 4
Fig. 1. Survival of Anastrepha obliqua larvae after been exposed inside
the fruits to gas mixtures containing 30% CO2 and 1% (circles), 3%
(squares) or 5% (diamonds) O2.
Fig. 2. Survival of Anastrepha obliqua larvae after been exposed inside
the fruits to gas mixtures containing 70% CO2 and 1% (circles), 3%
(squares) or 5% (diamonds) O2.
Fig. 3. Hue angle of mango mesocarp exposed to gas mixtures containing
70% CO2 and 1% (circles), 3% (squares) or 5% (diamonds) O2.
Fig. 4. Reducing sugars in mangoes treated with gas mixtures containing
70% CO2 and 1% (circles), 3% (squares) or 5% (diamonds) O2.
Fig. 5. Physiological weight loss in mangoes exposed to atmospheres containing 30% CO2 and 1% (circles), 3% (squares) or 5% (diamonds) O2.
Fig. 6. Soluble solids (°Brix) of mangoes stored in atmospheres containing 1%
O2 and 30% (circles), 50% (squares) or 70% (diamonds) CO2.
Fig. 7. Changes in mesocarp pH of mangoes exposed to atmospheres containing
1% O2 and 30% (circles), 50% (squares) or 70% (diamonds) CO2.
Fig. 8. Fruit hardness measured as resistance to penetration of mangoes exposed to atmospheres containing 1% O2 and 30% (circles), 50% (squares) or
70% (diamonds) CO2.
74
Journal of Applied Horticulture
Overall acceptance
14
12
ab
10
8
ab
Treated
Control
ab
Fig. 9
b
ab
a
deficiencies during growth in the tree (Krishnamurthy, 1981). It
has also been reported (Esguerra et al., 1990; Yahia, 1998) that
the same type of spoilage may be attributed to alterations of
starch metabolism and a toxic effect by ethanol and acetaldehyde
produced during anaerobic respiration, or even by hydrothermal
treatments in Carabao mangoes.
6
4
2
0
3301
3501
Treatment
3701
Fig. 9. Sensory evaluation scores of mangoes that were treated
for 3 days in atmospheres containing 1% O2 and 30% (3301), 50%
(3501) or 70% (3701) CO2. Error bars indicate standard deviation.
differences in soluble solids by the fifth day of treatment. It
appears that elevated CO2 concentrations interfere with the
conversion of starch into simple sugars (Kader, 1986;
Weichmann, 1986), which constitute the majority of the soluble
solids in mango (Krishnamurthy and Subramanyam, 1973).
Mango pulp pH did not display any difference as a consequence of
all treatments during the first four days of treatment, but changes
occurred by the fifth day and pH of CA treated mangoes remained
low, compared to control mangoes (Fig. 7). Kader (1986) reported
that pH remains low in fruits stored under CA due to two factors:
When metabolism is reduced, loss of acids from the Krebs cycle is
reduced and these acids accumulate. Secondly, enhanced dissolved
CO2 diffuses from the environment into the fruit tissue is utilized
for synthesis of organic acids, mainly malic acid.
Hardness of the fruits was measured to be 12 kgf/cm2 (Fig 8) upon
arrival. The hardness decreased to 2.74 kgf/cm2 after 5 days of
ripening. There was no statistical difference in textural patterns
of softening between treated and control mangoes, which
suggests that short-term exposure to CA had no deleterious
effects on fruit firmness. There is good correlation between loss
of firmness and increased polygalacturonase activity in mangoes
(Gomez-Lim, 1993). According to Kader et al. (1989)
polygalacturonase activity is depressed when fruits are exposed
to low O2 and high CO2 levels. However, Lakshminarayana and
Subramanyam (1970) reported softer texture in “Alphonso”
mangoes that were exposed to atmospheres prepared with initial
concentrations of 5, 10 or 15% CO2 for 21 days. These sets of
results can not be strictly compared because of the different CO2
levels and times of treatment.
Sensory evaluation of fully ripened mangoes demonstrated the
absence of non-typical aromas, and off-flavors or texture changes
in mangoes treated with CA for three days with 1% O2 and either
30, 50 or 70% CO2. There were no sensory differences in overall
acceptance of mangoes subjected to CA with 1% O2 and either
30 or 50% CO2, however, mangoes treated with CA containing
70% CO2 were judged as neither liked nor disliked, or even
unacceptable (Fig. 9).
Table 2 reports the incidence of mangoes that suffered injuries
and were judged as unacceptable following exposure to CA.
Symptoms of spoilage were necrotic spongy tissue, damage that
is also known as internal breakdown. It is known that this
symptom can develop during ripening due to nutritional
From the results reported herein, it may be concluded that
exposure for 3-5 days at 25 °C to the CA with 1% O2 and either
30 or 50% CO2 exerted an insecticidal effect without affecting
the wholesomeness of the mangoes. However, 20-25% of the
fruits showed signs of internal breakdown. The CA treatment
with 1% O2 and 70% CO2 was also an effective disinfestant
atmosphere, but affected the chemical composition and sensory
attributes of the mangoes. Additionally, this treatment induced
breakdown in 65% of fruits.
As Yahia and Paull recommended (1997), our results also suggest
the possibility of utilization of CA to kill fruit fly larvae with
little effect on fruit quality and should provide mango producers
with an alternative treatment for exporting mangoes to foreign
markets.
References
Balock, J.W. and D.F. Starr, 1945. Mortality of mexican fruit fly in
mangoes treated by the vapor-heat process. J. Econ. Entomol.,
38(6): 646-651.
Benschoter, C.A. 1987. Effects of modified atmospheres and
refrigeration temperatures on survival of eggs and larvae of the
Caribbean fruit fly (Diptera: Tephritidae) in laboratory diet. J. Econ.
Entomol., 80(6): 1223-1225.
Brandl, D.G., E.L. Soderstrom and F.E. Schreiber, 1983. Effects of
low-oxygen atmospheres containing different concentrations of
carbon dioxide on mortality of the navel orange worm, Amyelois
transitella walker (Lepidoptera: Pyralidae). J. Econ. Entomol.,
76(4): 828-830.
Celedonio-Hurtado, H. 1992. “Hydrothermal treatment as postharvest
quarantine treatment of mango”. CICMF. VI International course
on fruit flies, Volume II, pp. 87-93.
Coates, L.M., G.I. Johnson and A.W. Cooke, 1993. Postharvest disease
control in mangoes using high humidity hot air and fungicide
treatments. Ann. Appl. Biol., 123: 441-448.
Esguerra, E.B., S.R. Brena, M. U Reyes,. and M.C.C. Lizada, 1990.
Physiological breakdown in vapor heat-treated “Carabao” mango.
Acta Hort., 425-432.
Gomez Lim, M.A. 1993. Mango fruit ripening and molecular biology.
Acta Hort., 341: 484-499.
Hatton, T.T. 1991. Reduction of chilling injury with temperature
manipulation. In C.V. Wang (Eds.), Chilling injury of horticultural
crops pp. 269-280. Boca Raton, Florida: CRC Press, Inc.
Heard, T.A., N.W. Hesther and P.M. Peterson, 1992. Relative tolerance
to vapor heat treatment of eggs and larvae of Bactrocera tryoni
(Diptera: Tephritidae) in mangoes. Acta Hort., 85(2): 461-463.
Jagtiani, J., H.T. Chan and W.S. Sakai, 1988. Mango. In: Tropical Fruit
Processing pp. 2-5,45-105. San Diego: Academic Press, Inc.
Jay, E. 1984. “Recent advances in the use of modified atmospheres for
the control of stored-product insects”, Insect management for food
storage and processing. J.F. Baur, Ed. American Association of
Cereal Chemists. St. Paul, Minnesota. pp. 241-253.
Kader, A.A. 1986. Biochemical and physiological basis for effects of
controlled and modified atmospheres on fruits and vegetables. Food
Technol., 40: 99-104.
Postharvest disinfestation of mango with controlled atmospheres
75
Kader, A.A., D. Zagory and E.L. Kerbel, 1989. Modified atmosphere
packaging of fruits and vegetables. Crit. Rev. Food Sci. Nutr., 28(1):
1-31.
Soderstrom, E.L. and D.G. Brandl, 1984. Low-oxygen atmosphere for
postharvest insect control in bulk-stored raisins. J. Econ. Entomol.,
77(2): 440-445.
Krishnamurthy, S. 1981. Chemical studies on internal breakdown in
Alphonso mango (Mangifera indica Linn.). J. Hort. Sci., 56(3):
247-250.
Soderstom, E.L. and D.G. Brandl, 1985. Controlled atmospheres to
reduced post harvest insect damage to horticultural crops. S.M.
Blankenships, Eds. Controlled atmospheres for storage and transport
of perishable agricultural commodities. Raleigh, N.C. pp. 207-211.
Krishnamurthy, S. and Subramanyam, H. 1973. Pre- and post-harvest
physiology of the mango fruit: a review. Trop. Sci., 15(2): 167193.
Lakshminarayana, S. and H. Subramanyam, 1970. Carbon dioxide
injury and fermentative decarboxylation in mango fruit at low
temperature storage. J. Food Sci. Technol., 7(3): 148-152.
Landolt, P.J., D.L. Chambers and V. Chew, 1984. Alternative to use
of Probit 9 mortality as a criterion for quarantine treatments of fruit
fly (Diptera: Tephritidae)- infested fruit. J. Econ. Entomol., (77):
285-287.
León, D.M. and H.S. García, 1999. Role of controlled atmospheres on
mango storage, In: Advances in Mango Research, Vol. 1. Prem
Printing Press, Lucknow, India.
Lidster, P.D., Sanford, K.H. and McRae, K.B. 1981. Effects of modified
atmosphere storage on overwintering populations of the apple rust
mite and European red mite eggs. HortSci., 16(3): 328-329.
Lidster, P.D., K.H. Sanford and K.B. McRae, 1984. Effects of
temperature and controlled atmosphere on the survival of
overwintering populations of European red mite eggs on stored
‘McIntosh’ apples. HortSci., 19(2): 257-258.
McIntyre, A., L.D. Wickham, L.A. Wilson and A. Malins, 1993. Hot
water treatment for the postharvest control of fruit fly and
anthracnose in the Caribbean mango ‘Julie’. Acta Hort., 341: 533539.
Miller, G.L. 1959. Use of Dinitrosalicylic acid reagent for determination
of reducing sugar. Anal. Chem., 31: 426-428.
Mitchell, F.G. and A.A. Kader, 1992. “Postharvest treatments for insect
control”, Postharvest Technology of Horticultural Crops. A.A.
Kader, Ed. University of California, Okland, California. pp. 161165.
Rojas, V.R. 1993. “Evaluation of the insecticidal controlled atmospheres
on physico-chemical and sensory quality of mangoes”. M.Sc. Thesis,
Instituto Tecnológico de Veracruz.
Soderstrom, E.L. D.G. Brandl and B. Mackey, 1990. Responses of
codling moth (Lepidoptera: Tortricidae) life stages to high carbon
dioxide or low oxygen atmospheres. J. Econ. Entomol., 83(2):472475.
Soderstrom, E., B.E. Mackey and D.G. Brandl, 1986. Interactive effects
of low-oxygen atmospheres, relative humidity and temperature on
mortality of two stored-product moths (Lepidoptera: Pyralidae). J.
Econ. Entomol., 79(5): 1303-1305.
Toledo, A.J., H.W. Enkerlin and R.M.E. Bustos, 1992. “Gamma (Co60)
irradiation of fruits as quarantine treatment”. CICMF. VI
International course on fruit flies. Volume II, 77-85.
Weichmann, J. 1986. The effect of controlled-atmosphere storage on
the sensory and nutritional quality of fruits and vegetables. Hort., ,
Rev., 8, 101-127.
Windeguth, D.L. 1986. Gamma irradiation as a quarantine treatment
for caribbean fruit fly infested mangos. Proc. Fla. State Hort. Soc.,
99: 131-134.
Yahia, E.M. 1993. Responses of some tropical fruits to insecticidal
atmospheres. Acta Hort., 343: 371-376.
Yahia, E.M. and M. Tiznado-Hernandez, 1993. Tolerance and responses
of harvested mango to insecticidal low-oxygen atmospheres.
HortSci., 28 (10): 1031-1033.
Yahia, E.M. and L. Vazquez-Moreno, 1992. Responses of mango to
insecticidal oxygen and carbon dioxide atmospheres. Lebens. Wiss.
u. Technol., 26: 42-48.
Yahia, E.M. and R.E. Paull, 1997. The future for modified atmospheres
(MA) and controlled atmosphere (CA) uses with tropical fruits.
Chronica Hort., 18-19.
Yahia, E.M. 1998. Modified and controlled atmospheres for tropical
fruits. Hort. Rev., 22: 123-183.