EFFECTS OF MODIFIED ATMOSPHERE PACKAGING USING ACTIVE BAGS ON
THE SHELF LIFE AND QUALITY OF MANGO FRUITS
DANIEL MUTAHI KARUGAA85/3487/2010
SUPERVISOR: DR. JANE AMBUKO
INTRODUCTION Horticulture contributes significantly to the Kenya's
economy.
It is ranked the third most important foreign
exchange earner in Kenya after tourism and tea
respectively contributing 60% of the total export
earnings .
Mango is ranked 2nd after avocado in the fruit
industry.
Currently, there is an increasing demand for mango
locally, regionally & internationally leading to
increased production
Problem statement and justification Mango fruits being climacteric have a short shelf life(6-10
days) and are highly perishable.
This attributes are the main causes of post harvest losses in
the fruit.
There is need to use the applicable technologies to prolong
the shelf life of mango and maintain quality.
Packaging fruits under modified atmosphere is one of the
techniques employed to prolong fruit shelf life .
Active bag® packaging is a form of modified atmosphere
packaging that controls and prevents excessive water loss
from the packaged fruits enhancing fruit shelf life and
prevent shriveling
It also slows down metabolic processes such as respiration
through a modified in-pack gas composition.
Objective and hypothesis
OBJECTIVE
To evaluate the efficacy of modified atmosphere packaging using Activebag® to extend the postharvest shelf life of Ngowe and Apple mango fruit varieties.
HYPOTHESIS
The effect of Activebag® packaging on postharvest shelf life of mango fruit variet‘Apple’ and ‘Ngowe’ will not be different from that of ordinary bags .
Materials and method
Ngowe and Apple mango fruits (75% ripe) were harvested from commercial farms in Embu.
NGOWE MANGO
APPLE MANGO
Sampling ProcedureThe fruits were divided into 3 batches of 42 fruits for each
variety and labeled.
The 1st batch was packaged into commercially used polythene bags. The 2nd batch was packaged into Activebag®. The 3rd
batch was left unpackaged to serve as the control. ( Each treatment was replicated three times)
The packaged fruits, a self-sealing septum was inserted into the bags and tied from outside using rubber bands to facilitate measurement of changes in head-space gases (CO2 and Ethylene) every 2 days.
From the other packaged bags and control batch , 3 fruits were randomly sampled every 4 days for determination of other ripening related changes
The experimental design was completely randomized design (CRD) with 3 treatments and 3 replications
Analysed parameters
Cumulative weight – Digital weighing balance
Ethylene Evolution – Gas chromatograph
Respiration rate – Gas chromatograph
Peel and flesh Color – Color meter
0Brix(Total soluble solids) – Digital refractometer
Total titratable acidity – Titration with 0.1NaOH
Peel and flesh firmness- Penetrometer
Data is presented as means of replicates (6
or 3) with standard deviation
RESPIRATION AND ETHYLENE EVOLUTIONAPPLE NGOWE
Respiration and Ethylene levels increased in all the treatments upto a peak then reduced
Active bags are a form of MAP thus the trends for low CO₂ and ethylene levels in the
active bags compared to Control and Ordinary bags.
Also, active bags are fitted with ethylene absorbers which removed C2H4 from the
internal environment.
0
10
20
30
40
50
60
70
80
90
0 2 4 6 8 10 12 15
CO
2(m
L/K
G/H
R)
DAP
CONTROL
OB
AB
0
10
20
30
40
50
60
70
80
90
0 2 4 6 8 10 12 15
RES
PIR
ATI
ON
(mL/
KG
/HR
)
DAP
CONTROL
AB
OB
0
5
10
15
20
25
30
35
0 2 4 6 8 10 12 15
C2
H2
(uL/
KG
/HR
DAP
control
OB
AB
0
5
10
15
20
25
30
35
0 2 4 6 8 10 12 15
C2
H2
(uL/
KG
/HR
DAP
control
OB
AB
PEEL COLOR
APPLE NGOWE
0
20
40
60
80
100
120
140
0 4 8 12 15
HU
E A
NG
LE
DAP
APPLE
CONTROL PEEL
OB PEEL
AB PEEL
0
20
40
60
80
100
120
0 4 8 12 15 18
HU
E A
NG
LE
DAP
NGOWE
CONTROL PEEL
OB PEEL
AB PEEL
As the fruits ripened, peel hue angle reduced due change in color from green to yellow.
Packaged fruits retained a higher hue angle throughout the storage period with active
bag being the highest.
FLESH COLORAPPLE NGOWE
0
20
40
60
80
100
120
0 4 8 12 15
HU
E A
NG
LE
DAP
CONTROL FLESH
OB FLESH
AB FLESH
0
20
40
60
80
100
120
0 4 8 12 15 18H
UE
AN
GLE
DAP
CONTROL FLESH
OB FLESH
AB FLESH
As the fruits ripened, flesh hue angle reduced due change in
color from yellow towards orange.
Packaged fruits retained a higher hue angle throughout the
storage period with active bag being the highest in Ngowe mango.
FLESH FIRMNESS
APPLE NGOWE
0
5
10
15
20
25
30
35
40
45
50
0 4 8 12 15
FOR
CE(
N)
DAP
APPLE
CONTROL FLESH
OBFLESH
ABFLESH
0
5
10
15
20
25
30
35
1 2 3 4 5 6 7
FOR
CE(
N)
DAP
NGOWE
control flesh
Ob flesh
AB flesh
Firmness reduced with storageFruits packaged in active bag retained a higher flesh
firmness for both varietiesApple fruits retained a higher firmness compared to
ngowe fruits. in the package
PEEL FIRMNESS
APPLE NGOWE
0
10
20
30
40
50
60
70
0 4 8 12 15
FOR
CE(
N)
DAP
APPLE
CONTROL PEEL
OB PEEL
ABPEEL
0
5
10
15
20
25
30
35
40
0 4 8 12 13 15 18FO
RC
E(N
)DAP
NGOWE
control PEEL
OB peel
AB peel
%TTAAPPLE
NGOWE
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
1 2 3 4 5
%TT
A
DAP
control
OB
AB
0
0.05
0.1
0.15
0.2
0.25
0.3
1 2 3 4 5 6
%TT
A
DAP
CONTROL
OB
AB
TTA levels reduced with storage in both varieties.
Apple fruits had a higher %TTA levels than Ngowe fruits for all the
treatments.
Fruits packaged in Active bag maintained the highest %TTA levels
followed by Ordinary bag through out storage.
TOTAL SOLUBLE SOLIDSAPPLE
NGOWE
0
2
4
6
8
10
12
14
16
0 4 7 12 15 18
OB
RIX
DAP
APPLE
CONTROL
OB
AB
0
2
4
6
8
10
12
14
16
18
0 4 8 11 13 15 18
ob
rix
DAP
ngowe
CONTROL
AB
OB
In all the treatments and both varieties, °BRIX levels increased with
ripening
Fruits packaged in active bag retained the lowest °BRIX levels
compared to Ordinary bag and control for both varieties.
DISCUSSION AND CONCLUSIONActivebag® produced the longest shelf life compared to ordinary
bag and control because of their reduced rate of respiration and inhibition of ethylene production
Water loss was reduced in Active bag hence the slow loss in weight.
Consequently quality was preserved longer in Activebag followed by Ordinary bag ®.
Control fruits had the shortest shelf life and faster deterioration of quality.
Active bag packaging prolonged shelf life of both apple and ngowe mango fruits due to reduction in respiration and ethylene evolution consequently slowing down deterioration.
Apple mango fruits responded well to Packaging compared to Ngowe mango fruits
Active bag packaging could be used to prolong mango fruit shelf life and to maintain post harvest quality.