Agriculture Reference
In-Depth Information
Table 4.5
Examples of Storage Conditions Used Commercially for Citrus Fruit.
Activity
Valencia/navel oranges
Lemons
Mandarin
Grapefruit
Pre-cooling
conditions
Most packing houses do
not pre-cool, need
pulp temperature of
20°C for degreening
Most packing houses
do not pre-cool,
need pulp
temperature of
20°C for
degreening
Most packing houses
do not pre-cool,
need pulp
temperature of
20°C for
degreening
Most packing houses do
not pre-cool, need
pulp temperature of
20°C for degreening
Degreening
Ethylene 1-5 ppm
Ethylene 1-5 ppm
Ethylene 1-5 ppm
Early season
Temperature 20°C in
CA; 25C in FL
Temperature 20°C in
CA; 25C in FL
Temperature 20°C in
CA; 25C in FL
Ethylene 1-5 ppm
Humidity 90-95%
Humidity 90-95%
Humidity 90-95%
Temperature differences
in different areas
Carbon dioxide <1%
Carbon dioxide <1%
Carbon dioxide <1%
Humidity 95%
Optimum storage
temperature
3-8°C for 3 months
7-12°C for 6 months
5-8°C for 3-6 weeks
12-14°C for 6-8 weeks
Relative humidity
-
85-95%
85-90%
95%
Chilling sensitivity
Moderate susceptible
Most susceptible
Moderate susceptible
Moderate susceptible
Source: Perishable Products Export Control Board (PPECB 2009).
Table 4.6
Commercial temperature regime for export citrus.
Optimum carrying and minimum delivery air temperatures
(degrees Centigrade -°C) and fresh air ventilation
(cubic meters per hour - m3.h-1)
Commercial storing
temp (Shipping)
Optimum carrying
temperature
Minimum air delivery
temperature
Fresh air circulation
m3.h-1
Type of Citrus
Kumquats
4.5-11.0°C
Not given
Not given
Not given
Lemons
7.0-10.0°C
7.0°C
3.5°C
15
Oranges
4.5°C
3.5°C
2.5°C
15
Limes
Not given
11.0°C
7.0°C
15
Soft citrus
3.5°C
3.5°C
3.5°C
15
Source: Perishable Products Export Control Board (PPECB 2009).
can result in dehydration and the development of rind
disorders (Tugwell 1999).
(Fitzell & Muirhead 1983; Banik
et al
. 1998). Improper
cooling or interrupted cooling will also promote microbial
growth that will ultimately result in product spoilage
(Hobbs & Gilbert 1978). Yang and Irudayaraj (2003)
reported that the surface of produce that is exposed to
improper storage conditions could be susceptible to micro-
bial contamination. Jacobs and Korsten (2004) reported on
the presence and dominance of several
Penicillium
spp
prevalent in the citrus supply chain isolated from cold-
rooms at pack houses, ports, distributions centres and
retailers. Although it is well known that the cold chain
Cold chain management
Effective cold chain management is important to ensure
product integrity and prevent spoilage. Most crops benefit
from refrigeration, which slows down metabolism
and reduces water loss (Shewfelt
et al
. 1987, 1989).
Furthermore, low temperature storage conditions are gen-
erally not conducive to disease development and can thus
be exploited to ensure quality and extended shelf life
