Báo cáo nghiên cứu khoa học " Improvement of export and domestic markets for Vietnamese fruit through improved post-harvest and supply chain management " pot

1

CARD PROJECT 050/04 VIE

Improvement of export and domestic markets for
Vietnamese fruit through improved post-harvest and
supply chain management

Fruit Quality Comparisons of Three Cat Hoa Loc Mango
Supply Chains in Southern Vietnam



By Robert Nissen
1
, Ms San Tram Anh
2
, Ms Tran Thi Kim Oanh
2
, Mr Vu Cong Khanh
2
& Mr Ngo
Van Binh
2
,

1
Queensland Department of Primary Industries and Fisheries (DPI&F) , Maroochy Research
Station, PO Box 5083 SCMC, Queensland, Australia, 4560.
2
Southern Sub-Institute of Agricultural Engineering and Post-Harvest Technology (SIAEP), 54

Tran Khanh Du Street, District 1, Ho Chi Minh City, Vietnam.



2

FRUIT QUALITY COMPARISONS OF THREE CAT HOA LOC MANGO
SUPPLY CHAINS IN SOUTHERN VIETNAM.

Robert Nissen
1
, Ms San Tram Anh
2
, Ms Tran Thi Kim Oanh
2
, Mr Vu Cong Khanh
2
& Mr Ngo Van Binh
2
,

1
Queensland Department of Primary Industries and Fisheries (DPI&F) , Maroochy Research Station,
PO Box 5083 SCMC, Queensland, Australia, 4560.
2
Southern Sub-Institute of Agricultural Engineering and Post-Harvest Technology (SIAEP), 54 Tran
Khanh Du Street, District 1, Ho Chi Minh City, Vietnam.

INTRODUCTION
In Southern Vietnam, traditional wet market supply chains for agricultural fresh food are now giving way

to new supermarket-led supply chain systems. The rapid transformation in the fruit and vegetables
sector is due to the meteoric rise of supermarkets, hypermarkets, superstores, neighborhood stores,
convenience stores, discount stores in Southern Vietnam. This change is impacting on both the
upstream and downstream agricultural food supply chain participants through demands for safe, high
quality and sustainable-produced fresh products and the greatest impact is being felt by the small
farmers of southern Vietnam. Problems with traditional procurement supply chain practices include
low- or no product standards, supply inconsistencies, highly variable transaction costs and limited or
sequestered market information.

Supermarkets are now setting new procurement practices and supply systems which focus on reducing
costs and improving quality to enable them to sell at lower prices. This will allow them to win over
consumers and obtain a larger share of their target market. The ability of many small farmers,
collectors and wholesalers in the Mekong Delta of Vietnam to meet safe food levels and quality
demands of domestic and overseas supermarkets can only be obtained through investing in
improvements in their production and supply chain practices.

Implementation of new production and post–harvest practices and the modernisation of these supply
chains may prevent some small farmers from participating. Many small farmers will have to develop
risk minimisation strategies, such as forming groups, implementing new crop management and
production systems, improved packaging, more efficient transport methods and handling practices to
provide a safe, competitively priced quality product. Understanding how to develop new supply chains
and where to make changes is essential if farmers and all chain participants are to benefit. This CARD
Project set up experiments to evaluate the benefits of developing new improved supply chains for
mango in Southern Vietnam with farmer groups. The Cat Hoa Loc Mango
METHODOLOGY
This CARD Project set up three different value/supply chains. This was done to demonstrate to the
CARD project participants (farmers to retailers) the effects each supply chain product flows had on fruit
quality.

The mango variety “Cat Hoa Loc” was chosen as the variety to test and develop new value/supply

chains for, as it’s highly regarded and sought after by Vietnamese consumers.

Fruit assessments were carried out at the SIAEP laboratory in Ho Chi Minh City. After passing through
each of the respected supply chains a 100 fruit sample was taken on two occasions, Experiment 1 on
14
th
May 2008 and Experiment 2 on 1
st
June 2008.
3


Two separate experiment times were set up to verify the results obtained from the three supply chains.
SUPPLY CHAINS TRIALED
Three different value/supply chains were trialed. These were:
• Traditional supply chain (no change in technology or supply chain practices)
• New supply chain (new improved pre- and post-harvest technologies)
• Metro Cash and Carry cool supply chain (New improved pre- and post harvest technologies)

Due to extreme difficulties in tracking the fruit from the wholesale markets to retailers in Ho Chi Minh
City, it was decided that fruit samples be obtained when the fruit reached the wholesale markets in Ho
Chi Minh City for the Traditional and New supply chains. Fruit samples for the Metro chain were
obtained from Metro Cash and Carry Supermarkets after travelling the full length of the chain (See
Figure 1, 2 and 3).
T
RADITIONAL AND NEW SUPPLY CHAIN MAPS
For the Traditional and New Supply Chains without a cool chain component, a 100 fruit sample was
collected from the Cat Hoa Loc Mango Cooperative, Tien Giang province in Vietnam and transported to
SIAEP laboratory in Ho Chi Minh City by truck, whilst the rest of the fruit continued down the chain to
the retail market and consumer. The sampled fruit was placed in a room at SIAEP laboratory,

temperature 28-30
o
C, until ripe and then their quality assessed.

4

Figure 1. Traditional supply chain map.





Farmer
Harvests
fruit on
16/4/2008
Cat Hoa Loc
Mango
cooperative
Transport by
motorbike
Wholesaler
HCMC
Transport by
Truck
Bamboo
basket
Graded & pack in
35kg bamboo
baskets

Grade & pack in 35kg
bamboo baskets and
display for sale
Transport by
motorbike
Retailer
Consumer
Sample taken on
18/4/2008 by SIAEP in
HCMC
5

Figure 1. New supply chain map.






Farmer harvests
fruit with
secateurs and
leaves a long
20cm stem on
16/4/2008
Cat Hoa Loc
Mango
cooperative
Transport by
motorbike

Wholesaler
HCMC
Transport by
Truck
Graded & pack in
single layer
fiberboard trays
Transport by
motorbike
Retailer
Consumer
Fruit lowered
carefully to
ground and
stems trimmed
to 5-10mm in
length and sap
drained from
upside down
fruit
Bamboo baskets used but
only 3 fruit layers deep and
each fruit separated by
paper.
Fruit sanitised, and
treated for post-
harvest diseases
Sample taken on
18/4/2008 by SIAEP in
HCMC

6

Figure 3. Metro supply chain map.

M
ETRO COOL SUPPLY CHAIN MAP
For the Metro Cool Supply Chain fruit were transported from the pack house in Cai Be, Tien Giang
Province by air conditioned van (20-25
o
C) to Metro warehouse where the fruit were temporary placed in
the Metro warehouse cool room at 5-10
o
C for 6-8 hours. The fruit were then transported to the
supermarkets by a cold truck before 6:00 am of the next day, and displayed for sale at 20-25
o
C. Fruits
were collected from the supermarkets and placed in a cool room (20
o
C) at SIAEP laboratory until fruit
ripened.
Farmer harvests
fruit with
secateurs and
leaves a long
20cm stem on
16/4/2008
Cat Hoa Loc
Mango
cooperative
Transport by

motorbike
Metro HCMC
warehouse &
stored at 5-10
o
C
for 6-8 hours
Transport by air-conditioned
Van at 20-25
o
C
Graded & pack in
single layer plastic
trays
Transport
Metro cold
truck to
supermarkets
Metro
supermarkets
and displayed
at 20-25
o
C
Consumer
Fruit lowered
carefully to
ground and
stems trimmed
to 5-10mm in

length and sap
drained from
upside down
fruit
Bamboo baskets used but
only 3 fruit layers deep and
each fruit separated by
paper.
Fruit sanitised, and
treated for post-
harvest diseases
Sample taken on
18/4/200 by SIAEP in
HCMC
7

HARVESTING PROCEDURES AND PROCESSES
TRADITIONAL SUPPLY CHAIN
Fruit were harvested in the traditional manner on the 16/4/2008. Fruit are plucked from the tree by
hand or harvest stick and packed into rigid bamboo baskets. These fruit baskets are then transported to
the collector residence by motorbike. Fruit are then graded according the wholesalers standards,
placed in 35 kg rigid bamboo baskets for transport by truck to the wholesale markets in Ho Chi Minh
and samples collected on the 18/4/2008.
N
EW AND METRO COOL CHAIN
Fruit were harvested on the 16/4/2008 with a 20cm in length stalk either by cutting fruit from tree with
secateurs or by hand and breaking fruit off leaving a long stalk. Fruit were then placed into small
bamboo baskets lined with paper. Baskets of fruit were then gently lowered to the ground by rope.
Fruit were then removed and the stalk length cut to about 7cm. Harvested fruit then had their stems cut
to 5-10 mm in length, while being held upside-down. Fruit were then placed on paper on the ground in

the shade of the tree canopy to allow the sap to drain. Once the sap had stopped oozing from the fruit,
they were then packed gently into the rigid bamboo baskets with each fruit separated and baskets
packed no higher than 3 layers deep and taken to the packing shed by motorbike. If fruit the stems
were too long, they were re-cut at the packing shed to the correct length of 5-10mm. Once the fruit
reached the packing shed, they were sanitised and washed in clean fresh water within 24 hours of
harvesting. Fruit were graded by size and suspected immature fruit eliminated by flotation method.
Fruit were then immersed in a 52
o
C clean hot water dip for 5 minutes to prevent fruit quality losses from
post harvest diseases. Temperature was carefully controlled to within 0.5°C to prevent fruit damage.
An accurate thermometer was used to monitor temperatures in various parts of the dipping tank. Fruit
were then placed on sorting benches and fan dried, sorted and graded according to quality standards,
then packed into single layer trays (fiberboard cartons) and transported overnight to the Metro Cash &
Carry Retail market in Ho Chi Minh City were the 100 fruit samples were collected on the 18/4/2008 and
taken to SIAEP laboratory.
FRUIT MEASUREMENTS
External quality measurements for Experiment 1 were carried out on storage days 1, 3, 5, 6, 8, 10, and
for Experiment 2, storage days 2, 5, 10. All fruit sampled from each supply chain were from Class 1
grade. All internal fruit quality analysis was carried out once the fruit had ripened for both Experiments.
Assessments undertaken were:
• Average fruit weight in grams
• percentage moisture loss over time
• Skin colour (measurements taken using a Minolta Chromometer CR 200 and expressed as L a
b values)
• External quality measurements rated using the hedonic scale (1-9)
o External fruit appearance
o Visible area of external damage on the fruit:- Rub marks, abrasion damage, bruising or
pressure marks and sapburn recorded.
o Visible insect damage:- grub chew marks, thrip and mite damage etc.
o Visible disease damage:- anthracnose damage area, stem end rot area, bacterial black

spot and dendritic spot etc.
• Internal quality measurements
o Flesh colour (measurements taken using a Minolta Chromometer CR 200 and
expressed as L a b values)
o Sensory evaluation (taste, flavour and appearance ratings were based on the hedonic
scale of 1 to 9.
8

o Firmness was measured by hand held Effegi Penetrometer FT 001 using an 11mm tip
and force calculated as kg per cm
2
.
o Titrateable Acid measured using 10g of flesh and added 100mL of double distilled
water and macerated. This solution was then filtered through cotton wool and 10 mL of
juice was collected and 2 drops of phenolphalayene indicator was added and titrated
with Sodium Hydroxide (NaOH) 0.1 normal solution until colour change occurred.
o Total soluble solids or degree Brix, was measured using a temperature compensation
hand held Atago Refractometer Model N-1E.
• Vitamin C content was measured using Association of Analytical Chemists (AOAC)
International method 967.21. Procedure used was:
• Take 10 gram of fruit flesh and grind with 5 mL Metaphosphoric-acetic solution.
• Remove all sample and place into a 100mL flask and add Metaphosphoric-acetic
solution until it reaches 100mL and shake.
• Filter through absorbent cotton or rapid paper.
• Take 10ml of the above solution and place into a 100mL glass beaker
• Titrate this solution with 2,6 diclorophenol indophenolat natri until pink colour
appears. This takes about 2 minutes to occur (note number ml = X).
• Count amount of 2,6 DCPIP need to titrate 1mg acid ascorbic
 + Take 2mL standard acid ascorbic solution add 5mL
Metaphosphoric-acetic

 +Titrate with 2,6 diclorophenol indophenolat natri until pink colour
2 minute (note number ml : y)
• Titrate blank sample with 2,6 diclorophenol indophenolat natri until pink colour
appears. This takes about 2 minutes to occur (note number ml = B)
Calculation
Content of Vitamin C =
P
v
VFBX
.
100 ).(
−
(mg/100gram sample)
 X: number of ml 2,6 diclorophenol indophenolat natri titrate
sample
 V: extracting solution volume ( V = 100mL)
 v: extracting solution volume to titrate (v = 7mL)
 P: amount of sample ( p = 10g)
 F: number of mg ascorbic acid equivalent 1ml standard 2,6
diclorophenol indophenolat natri
( F=
Y
2
).
• Taste evaluations were carried out by an expert panel established at SIAEP laboratory using
the hedonic scale (1-9):-
1 = dislike very much
3 = dislike
5 = neither dislike or like
7 = like

9 = like very much

RESULTS
AVERAGE FRUIT WEIGHT
There were no significant differences between the three chains based on fruit weight sampled on the
18/4/2008 plus one day. Table 1 below indicates the average fruit weight for each supply chain.

9

Table 1: Average fruit weight as of the 19/4/2008
Sample description Traditional Supply
Chain average
fruit wt (g)
New Supply
Chain average
fruit wt (g)
Metro Cool Supply
Chain average
fruit wt (g)
Experiment 1 445.64 484.30 468.46
Experiment 2 448.39 434.78 440.90


FRUIT WEIGHT LOSS
For the Traditional and New Supply Chains, the fruit weight rate loss was greater than the sampled fruit
from the Metro Cool Supply Chain (Figures 4 and 5). Storage temperatures for the Traditional and New
Supply Chains were similar. There were no significant differences between the Traditional and New
Supply Chains for fruit weight loss over time for both Experiment 1 and Experiment 2 but when
comparing the Metro Cool Supply Chain to the Traditional and New Supply Chains for Experiment 1,
the weight loss rate was reduced by about 35% and for Experiment 2 the weight loss rate was reduced

by about 61%. Therefore, keeping mango fruit cool down the supply chain significantly reduces fruit
weight loss and extends shelf life by at least 2 to 3 days in the high humid temperature conditions in
Southern Vietnam. The hot dip treatment of mango fruit to prevent post-harvest diseases did not
appear to affect the fruit weight loss rate. Both the Traditional and New Supply Chains had similar fruit
weight loss rates over time for Experiment 1 and 2, but the fruit weight loss for the Metro Cool Supply
Chain was significantly slower for both Experiment 1 and 2 (Figure 4 and 5).






Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
Weight loss (%) after reaching wholesaler
0
2
4
6
8
10
12
14
16
Traditional supply chain
New supply chain
Metro cool supply chain

Figure 4. Comparison of the percentage of fruit weigh loss rate in for the Traditional, New and Metro
Cool Supply Chains for Experiment 1.
10

Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
Weight loss (%) after reaching wholesaler
0
2
4
6
8
10
12
14
16
Traditional
New
Metro

Figure 4. Comparison of the percentage of fruit weigh loss rate in for the Traditional, New and Metro
Cool Supply Chains for Experiment 1.





11

COLOUR READINGS
Minolta Chromameter CR 200 was used to determine skin colour changes of the sampled fruit. The
colour space measurements are:- L* colour space (positive values indicate lightness and negative
values indicate darkness), a* colour space (positive values indicate red hue as opposed to negative
values indicate greenness), and b* colour space (positive values indicate yellow and negative values
indicate blue).



Figure 5. L* a* b* colour space difference ∆E* ab





Lightness 25% Lightness 50% Lightness 75%
Figure 5. Colour diagrammatic representation of L* a* b* colour space values
Note: Colour show here may not be a true representation of colour observed by the naked eye as these colours patches are
dependent computer, screen and printer settings used to display or print this report.





12

S
KIN COLOUR READINGS
By looking at skin colour from the different supply chains, we have we have tried to determinate the

effects on freshness. Survey work conducted by the CARD Project 05004/ VIE found:
• Wholesalers prefer to purchase mangoes with long stalks (>10cm) attached, this is a sign of
freshness
• Wholesaler also prefer to purchase mangoes that are light green all over in colour as this is a
sign of freshness
• Under high temperature and high humidity conditions, mangoes in Vietnam ripen very quickly
and also breakdown quickly due to disease (anthracnose and stem end rots)
• Mango fruit in Vietnam do not ripen evenly due to the high temperatures during the ripening
phase (> 27
o
C)
• Fruit are often force ripened in temperature above 35
o
C by wholesalers
• Consumers in Vietnam prefer to eat Cat Hoa Loc mango fruit that have about 60 to 80% yellow
skin colour and a 40% to 20% very light green skin colour
• Consumers regard this green skin colour a sign of freshness
E
XPERIMENT 1 COLOUR SPACE READINGS
Comparison of representative colour space patches of fruit samples taken from the Traditional Supply
Chain, New Supply Chain and Metro Cool Supply Chain for Storage Day 1 and when fruit were classed
as full ripe for Traditional Supply Chain – Storage Day 6, New Supply Chain – Storage Day 8 and Metro
Cool Supply Chain – Storage Day 11 (Figures 6).




13

Tradition Supply Chain New Supply Chain Metro Cool Supply Chain


Storage Day 1
(L* 57.58, a* -14.20, b* 33.20)
Storage Day 1
(L*60.35, a* -15.77, b* 33.89)
Storage Day 1
(L* 58.87, a* -16.21, b* 31.13)


Storage Day 3
(L* 59.71, a* -13.89, b* 32.74)
Storage Day 3
(L*62.21, a*-14.13, b*35.39)
Storage Day 3
(L*6.38, a*-15.70, b*32.60)


Storage Day 6
(L* 61.96, a* -8.70, b* 39.09)
Storage Day 6
(L*64.37, a*-8.44, b*41.75)
Storage Day 6
(L*62.70, a*-14.66, b*35.23)




Storage Day 8

(L* 61.37, a* -8.16, b* 41.28)
Storage Day 8
(L*64.42, a*-12.27, b*40.78)




Storage Day 11
(L* 64.48, a* -2.97, b* 44.45)

Figure 6. Comparison of representative colour space patches of fruit samples taken from the
Traditional Supply Chain, New Supply Chain and Metro Cool Supply Chain for Experiment 1

Note: Colour show here may not be a true representation of colour observed by the naked eye as these colours patches are
dependent computer, screen and printer settings used to display or print this report.
14

EXPERIMENT 2 COLOUR SPACE READINGS
Comparison of representative colour space patches of fruit samples taken from the Traditional Supply
Chain, New Supply Chain and Metro Cool Supply Chain for Storage Day 1 and when fruit were classed
as full ripe for Traditional Supply Chain, New Supply Chain and Metro Cool Supply Chain – Storage
Day 9 (Figure 7)

Tradition Supply Chain New Supply Chain Metro Cool Supply Chain


Storage Day 1
(L* 58.09, a* -16.73, b* 31.20)
Storage Day 1
(L*58.90, a* -15.76, b* 31.55)

Storage Day 1
(L* 58.87, a* -16.21, b* 31.13)


Storage Day 5
(L* 59.95, a* -13.10, b* 36.84)
Storage Day 5
(L* 60.60, a* -12.19, b* 37.77)
Storage Day 5
(L* 58.57, a* -15.28, b* 34.60)


Storage Day 9
(L* 62.10, a* -1.00, b* 44.98)
Storage Day 9
(L* 64.53, a* -3.05, b* 46.63)
Storage Day 9
(L* 63.74, a* -10.27, b* 40.27)

Figure 7. Comparison of representative colour space patches of fruit samples taken from the
Traditional Supply Chain, New Supply Chain and Metro Cool Supply Chain for Experiment 2

Note: Colour show here may not be a true representation of colour observed by the naked eye as these colours patches are
dependent computer, screen and printer settings used to display or print this report.


15

SKIN L*COLOUR SPACE VALUES

Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
L* colour space after reaching wholesaler
56
58
60
62
64
66
Traditional supply chain
New supply chain
Metro cool supply chain

Figure 8. Comparison of the average L* colour space values for the Traditional, New and Metro Cool
Supply Chains for Experiment 1

Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
L* colour space after reaching wholesaler
56
58
60
62
64
66
Traditional supply chain

New supply chain
Metro cool supply chain

Figure 9. Comparison of the average L* colour space values for the Traditional, New and Metro Cool
Supply Chains for Experiment 2
For Experiment 1, fruit sampled for the Traditional (L* 57.58), New (L* 58.87) and Metro Cool Supply
Chains (L* 60.35) were of similar colour space lightness (Figure 6 and 8). Fruit from the Metro Supply
Chain achieved a slightly lighter colour (L* 64.48), 5% lighter than fruit from the Traditional (L* 61.73)
and New Supply Chains (L* 61.96), Figure 6 and 8. Fruit from the Traditional and New Supply Chains
lightened in colour at a similar rate, while fruit from the Metro Cool Supply Chain quickly lightened in
16

colour up until storage day 3, then slowed till storage day 6, and increased at a similar rate to storage
day 8 (Figure 8 ). The final L* colour space for the New Supply Chain dropped due high levels of
disease attack (Figure 8). Fruit of the Traditional Supply Chain fruit decayed quickly due to large areas
of the fruit being attacked by disease in Experiment ,1 therefore fruit could not be assessed past
storage day 6.

For Experiment 2 for the Traditional Supply Chain fruit did not change colour (lighten) at the same rate
compared to the New Supply Chain and Metro Cool Supply Chain due to disease attack (Figure 9).
Fruit from the Traditional Supply Chain were darker in colour on sample day 11.

For Experiment 1 and Experiment 2, the hot water dip treatment for disease and did not appear to affect
the rate at which the fruit lightened in colour for all three chains.

S
KIN A* COLOUR SPACE VALUES

Storage days +1 at 28-30
o

C after reaching wholesaler
024681012
a* colour space after reaching wholesaler
-20
-15
-10
-5
0
5
Traditional supply chain
New supply chain
Metro cool supply chain

Figure 10. Comparison of a* colour space values for the Traditional, New and Metro Cool Supply
Chains for Experiment 1.




17

Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
a* colour space after reaching wholesaler
-20
-15
-10
-5

0
5
Traditional supply chain
New supply chain
Metro cool supply chain

Figure 11. Comparison of a* colour space values for the Traditional, New and Metro Cool Supply
Chains for Experiment 2.


All fruit sampled from the Traditional, New and Metro Cool Supply Chains in Experiment 1 and 2 were
of similar green colour a* -14.20, a* -15.77, a* -16.21, a*-16.73, a* -15.76 and a* -16.07 respectively
(Figure 10 and 11). For Experiment 1 (Figure 10), the a* colour space values for fruit in the Traditional
and New Supply Chains less green and ripened quickly at storage day 6 and storage day 10
respectively compared to the Metro Cool Supply Chain. For the Metro Cool Supply Chain storage days
8 to 10 there was a very rapid colour change from with fruit loosing their greenish colour. In Experiment
2 the Metro Cool Supply Chain fruit failed to achieve the same colour space levels and were still
greenish at storage day 10 (Figure 11). The Metro Cool Supply Chain treatment appears to have
decreased the rate at which the a* colour space changed and the fruit loose their green colour.








S
KIN B*COLOUR SPACE VALUES

18

Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
b* cololur space after reaching wholesaler
30
32
34
36
38
40
42
44
46
48
Traditional supply chain
New supply chain
Metro cool supply chain

Figure 12. Comparison of b* colour space values for the Traditional, New and Metro Cool Supply
Chains for Experiment 1.

Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
b* cololur space after reaching wholesaler
30

32
34
36
38
40
42
44
46
48
Traditional supply chain
New Supply chain
Metro cool supply chain

Figure 13. Comparison of b* colour space values for the Traditional, New Supply Chains and Metro
Cool Supply Chain for Experiment 2.

The Traditional Supply Chain fruit in both Experiment 1 and 2 did not achieve the same yellow colour
levels compared to fruit from the New Supply Chain and Metro Cool Supply Chain (Figures 12 -18).
Fruit from the Metro Cool Supply Chain coloured the slowest in both Experiment 1 and 2 (Figures 10-
18). In Experiment 2 the fruit from the Metro Cool Supply Chain were 10% and 14% lower in yellow
colour than the Traditional and New Supply Chains respectively (Figure 13).

19

The Traditional Supply Chain fruit skin wrinkled severely due to water loss compared to the New and
Metro supply chain for Experiment 1 and 2. Fruit from the Metro supply chain ripened the slowest in
both Experiment 1 and 2 (Table 2 & 3). In Experiment 1 the Metro supply chain fruit attained a slightly
deeper yellow colour (b* 44.45) compared to the Traditional (b* 39.09) and New Supply Chains (b*
41.28), but in Experiment 2 the fruit were greener and less coloured that the Traditional and New
Supply Chains. In both Experiment 1 and 2, skin colour for the Traditional Supply Chain did not

achieve an even yellow colour all over the fruit due to fruit breakdown from disease (Figure 5, 6, 7, 8 &
9).


Fruit in The Metro Cool supply Chain ripened at a slower rate, therefore employing a cool chain under
the high temperature humid conditions in southern Vietnam has had a significant effect in reducing
mango fruit respiration rates and the ripening process as well as controlling the rate of disease
infestation.




Figure 14. Experiment 1 comparison of fruit skin colour storage day 6




METRO chain New chain
Traditional chain
20


Figure 15. Experiment 1 comparison of fruit skin colour storage day 8

Figure 16. Experiment 1 Metro supply chain fruit skin colour storage day 10




METRO chain

New chain
Traditional chain
METRO chain
METRO chain
21


Figure 17. Experiment 2 comparison of fruit skin colour storage day 5



Figure 18. Experiment 2 comparison of fruit skin colour storage day 9



New chain Metro chain
METRO chain
Traditional chain
New chain
Traditional chain
22

DEFECTS AND DISEASE INCIDENCE
EXPERIMENT 1
For Experiment 1, fruit collected from the Traditional Supply Chain system had the highest level of
disease infestation - about 15% of the fruit sampled were infected with disease, compared to 6% for the
Metro Cool Supply Chain and 0% for the New Supply Chain at storage day 1 (Figure 19). By storage
day 6, 93% of the fruit in the Traditional Supply Chain were infected with disease compared to the New
Supply Chain with 55% and the Metro Cool Supply Chain 5% of fruit infected. On storage day 8 and
storage day 10 for the Metro Supply Chain, the amount of fruit affected by disease increased rapidly

from 6% to 33% (storage day 8) and 63% (storage day 10) respectively (Figure 1).

In the Traditional and New Supply Chains, fruit were saleable for only 4 days before disease severely
affected the fruit quality. Therefore, fruit from the Traditional and New Supply Chains were not
assessed on storage day 8 and storage day 10. The mango diseases, Anthracnose, Stem End Rot and
Black Spot were the major diseases observed. These diseases spread rapidly from fruit to fruit and the
percentage rate increase per day of fruit being infected with disease for the Traditional Supply Chain
was 22%, 29% for the New Supply Chain and 24% for the Metro Cool Supply Chain. Measurements
taken on the disease area and rate of increase in size per day were 22% for the Traditional Supply
Chain, 16% for the New Supply Chain and 11% for the Metro Cool Supply Chain.
E
XPERIMENT 2
For Experiment 2, the amount of fruit affected with disease was; Traditional Supply Chain - 15%, New
Supply Chain 10% and Metro Cool Chain 20%. By storage day 4 the Traditional Supply Chain had
increased to 60%, New Supply Chain 30% with the Metro Cool Supply Chain remained at 20% (Figure
20). By storage day 8, the amount of fruit affected by disease for the Traditional Supply Chain was
95%, New Supply Chain 75% and Metro Cool Supply Chain increased by 10% to 30%.

Fruit from the Traditional and New Supply Chains were not assessed on storage day 10 due to the fruit
breaking down from Anthracnose, Stem End Rot and Black Spot diseases. Fruit from the Metro Cool
Supply Chain were assessed on storage day 10 and the amount of fruit with disease had increased
from 33% to 55%. These diseases also spread rapidly from fruit to fruit with 23% percentage rate
increase per day of fruit being infected for the Traditional Supply Chain, 25% for the New Supply Chain
and 12% for the Metro Cool Supply Chain. Measurements taken on the disease area and rate of
increase in size per day for Experiment 2 were slightly greater than Experiment 1 with a rate of 25% for
the Traditional Supply Chain, 17% for the New Supply Chain and 13% for the Metro Cool Supply Chain.
P
OSTHARVEST DISEASE CONTROL MEASURES
N
UMBER OF FRUIT INFECTED

Comparison for the number of fruit infected with disease (Anthracnose, Stem End Rot and Black Spot)
for the Traditional Supply Chain (control, no postharvest disease treatment) and New Supply Chain (hot
water dipping treatment for disease control) on storage day 8 (final measurements) we found a
reduction in fruit disease infection rate for experiments 1 and 2 of 41% and 48% respectively.
Comparing for the number of fruit infected with disease (Anthracnose, Stem End Rot and Black Spot)
for the Traditional Supply Chain (control, no postharvest disease treatment) to the Metro Cool Supply
Chain System (Hot water dipping plus the implementation of a cool chain), final measurements storage
day 8 (Traditional) to storage day 10 (Metro) we found for Experiment 1 and 2 a reduction in fruit
disease infection rate of 32% and 42% respectively, while comparisons based on storage day 8 for the
Traditional Supply Chain and Metro Cool Supply Chain System showed in greatest decrease in
infection rates of 64% and 68% respectively.

23

Comparison of the New Supply Chain (hot water dipping treatment for disease control) to Metro Cool
Supply Chain System (Hot water dipping plus the implementation of a cool chain) for storage day 8 for
Experiment 1 and 2 showed the number of fruit infected was 39% and 46% less. Fruit from the Metro
Cool Supply Chain in Experiment 1 and 2 for the first 6 storage days had no increase in the amount of
disease affecting the fruit (Figures 18 and 19).



Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
Percentage (%) of fruit affected by
disease after reaching wholesaler
0
20

40
60
80
100
Traditional Supply Chain
New Supply Chain
Metro Cool Supply Chain

Figure 19. Comparison of the percentage of the fruit affected by disease in Experiment 1 for the
Traditional Supply Chain, New Supply Chain and the Metro Cool Supply Chain













24

Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
Percentage (%) of fruit affected by

disease after reaching wholesaler
0
20
40
60
80
100
Traditional Supply Chain
New Supply Chain
Metro Cool Supply Chain

Figure 20. Comparison of the percentage of the fruit affected by disease in Experiment 2 for the
Traditional Supply Chain, New Supply Chain and the Metro Cool Supply Chain


F
RUIT AREA OF INFECTION
Comparing the increase in disease area per day (rate at which disease spread on the fruit) for the
Traditional Supply Chain (control, no postharvest disease treatment) and New Supply Chain (hot water
dipping treatment for disease control) on day 8 we found a reduction in fruit disease infection rate for
experiments 1 and 2 of 83% and 73% respectively (Figures 21 and 22). Comparing the increase in
disease area per day (rate at which disease spread on the fruit) for the Traditional Supply Chain
(control, no postharvest disease treatment) final measurement day 8 to the Metro Cool Supply Chain
System (Hot water dipping plus the implementation of a cool chain) day 10 we found for Experiment 1
and 2 a reduction in fruit disease infection rate of 81% and 71% respectively, but comparisons based
on day 8 for the Traditional Supply Chain and Metro Cool Supply Chain System showed in greatest
decrease in infection rates of 88% and 79% respectively.

Comparison of the New Supply Chain (hot water dipping treatment for disease control) to Metro Cool
Supply Chain System (Hot water dipping plus the implementation of a cool chain) for day 8 for

Experiment 1 and 2 showed the area of infection per fruit was 28% and 22% less.






25

Storage days +1 at 28-30
o
C after reaching wholesaler
024681012
Average percentage (%) area of disease
on fruit after reachin wholesaler
0
20
40
60
80
Traditional Supply Chain
New Supply Chain
Metro Cool Supply Chain

Figure 21. Comparison of the percentage of the area of the fruit affected by disease in Experiment 1 for
the Traditional Supply Chain, New Supply Chain and the Metro Cool Supply Chain.


Storage days +1 at 28-30
o

C after reaching wholesaler
024681012
Average percentage (%) of area of diseaase
on fruit after reaching wholesaler
0
20
40
60
80
Traditional Supply Chain
New Supply Chain
Metro Cool Supply Chain

Figure 22. Comparison of the percentage of the area of the fruit affected by disease in Experiment 2 for
the Traditional Supply Chain, New Supply Chain and the Metro Cool Supply Chain.
FRUIT EXTERNAL APPEARANCE
Rating of fruit appearance using the hedonic scale (1-9) in Experiment 1 showed that the fruit of the
Traditional Supply Chain did not reach acceptable levels (Figure 21). Fruit shriveled due to significant
moisture loss. Disease levels were also high and the and severely affected the fruit appearance. Most
fruit were un-saleable by storage day 6. Fruit of the New Supply Chain and Metro Supply Chain were
highly desirable. Fruit of the New Supply Chain achieved an excellent appearance, scale rating 8 on
storage day 5 and then dropped slightly to 7 (Figure 21) and a similar effect was also found with the
fruit from the Metro Cool Supply Chain. The mango fruits of Metro Cool Supply chain remained fresh,
green, hard, and brightly green colour upon ripening the colour changed to nice yellow as did the fruit
from the New Supply Chain.