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

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

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

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

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

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

 +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

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



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

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

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


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

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


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

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

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

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

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.