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1Leendert Saarloos
Fruit vegetables
Still live on in the cold store !
2
Some plant fhysiology
Oxygen O2
Respiration heat
Carbondioxide CO2
Water H2O
Ethylene C2H4
3
Heat of respiration
Depending of Product
Depending of the ambient temperature
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Heat production different product
Heat production (kcal/Ton in 24 Hr)
in relation to the storing temperature (°C) 3
4
5
6
0 5 10 15 20 Patato 380 325 400 575 700 Apple 165 355 530 885 1.200 Tomato 320 425 750 1.450 1.875 With cabage 340 475 700 1.125 2.250 Gurka 405 600 1.150 2.225 3.375 asparagus 1.275 1.650 3.150 5.000 6.750 China cabage 1.100 1.680 3.480 5.600 8.500 cauliflower 1.200 2.400 4.075 5.630 10.400 mushroom 2.400 3.200 5.100 9.800 12.800 Sallad 2.480 4.000 5.450 7.300 11.000
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Important: fast cooling down
To have good quality on the end of the chain, you must
cool as quick as possible the fruit down!!!!!!
Do not wait with bringing in the fruit into the cold store!
By example: apple 20 °C 1200 : 165 = 7,3 days lost of
store live
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Carbondioxide and Ethylene
Carbon dioxide and Ethylene are poisonous
It must be taken out of the room!
In ULO store CO2 is a narcotic
Lower temperature less production of CO2 and C2H4
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Water lost coming from product
Every cooling action is lost of water = Quality product
Insulation of the cold store room is imporatant, good
insulation is less cooling action.
Water lost product in relation to humidity of environment
Humidity is depending on the cooling installation
Pears are very sensetive for water lost
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Figures from the field
The smaller the temperature different, the smaller the the water loss of the product!
Temperature differents of 4 º C is only possible with glycol cooling.
Be carefull: not all coolers can work with small temperature differents !!!
Cold store room
Temperature
Evaperator
Temperature
Temperature
Differents
Relative
humidity
+1 °C 7 °C 8 °C 85-92 %
+1 °C 4 °C 5 °C 92-94 %
+1 °C 3 °C 4 °C 97-98 %
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Relation of cooler temp. and room temp.
4 5 6 7 8 9 10 11 12
DT1 in K
70
75
80
85
90
95
100
rel.
hu
mid
ity a
ir i
n %
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Bassic things need for good cooling
Good insulation
High humidity
Good air circulation
Temperture regulation which you can trust
Frost protection is your insurence
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insulation
Insulation 10 cm polyurethane
15 cm polystyrene
Good closing doors
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Humidity and air
High quality cooler, and big coolers
Air space for air circulation
Close the air space around the cooler
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Example of closing around the cooler
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Short cut air is not cooling product
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Temperature control and frost protection
Temperature product
Start and stop cooling
Frost protection
Defrost sensor low in cooler
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Important
Spend money for a good temperature control
A frost protection is your insurance, for a little money can
you sleep well
Calibrate your sensors
With melting ice
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Floor plan for apple boxes
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10
35
4Min. sizes in cm
35
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Cooling capacityC
oo
lin
g c
ap
acit
y
KW
Day 10Bring in pr. Long time storing
Heat transmission
Ventilator heat
Fresh air
Respiration heat
Field heat
Lost of door, forklift and people
Respiration heat Field pr.
0
5
10
15
20
25
30
35
40
45
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What is ULO storing
The oxygen content in an apple store
needs to be strongly decreased for
Controlled Atmosphere storage, e.g.:
• Apples 1-1.2%
• Pears 2-3%
To prevent ambient air from entering the store, it has to be absolutely gastight
The green line shows the optimal storage life
The black line shows a decrease of respiration at lower O2 levels
Fermentation (red line) at extreme low oxygen, however, will lead to decay
% O220
0
Maximum
storage time
Respiration
Optimal O2 level
Set-point conditions
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ULO (Ultra Low Oxygen)
Turn over O2
to CO2
ca 1% per 24 Hr.O2
CO2
O2 & CO2 Analyser
CO2
CO
2S
cru
bb
er
O2
N2
VP
SA
GE
N.
N2
air
O2 Air+DP < 12 mm WS
Under pressure
valve
> 12 mm WS Over pressure valve
N2 and O2
N2 and O2
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Saarloos for insulation and doors
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Saarloos build pipelines stainless steel
