Application of Modified Atmosphere Packaging on Quality of Selected Vegetables: A Review - Application of Modified Atmosphere Packaging on Quality of Selected Vegetables - page 54

at 5 °C, the use of fi lm A proved benefi cial with mesophile and Enterobacteriaceae
counts being around 7 log/CFU/g at the end of storage thus prolonging the shelf life
up to 14 days.
Simon et al. ( 2004 ) evaluated the microbiological, quality and sensorial charac-
teristics of white asparagus washed with chlorine or water and packaged under
MAP (perforated PVC and P-Plus 160 fi lms used) at 4 °C for 15 days. P-Plus had
the lowest weight loss (0.2 %) while samples in PVC suffered higher losses (5.5 %).
Water and chlorine treatment caused a reduction in mesophile and psychrotroph
initial counts by 1 to 1.5 log cycles. Enterobacteriaceae counts in P-Plus packages
were 1.6 logs higher on water washed samples (6.5 and 4.9 log CFU/g for water and
chlorine treatments, respectively) (Table 1.4 ).
White asparagus spears were over-wrapped with a 16 mm stretch fi lm (in 5 L
glass jars with ethylene—free air passing through) and kept at 2.5, 5, 10, 15, 20 and
25 °C under darkness or light for 6 days. Ethanol in spear tissues was shown to
increase linearly with storage temperature (100 and 800

L/L at 2.5 and 20 °C,
respectively). Weight loss of samples stored at 2.5-15 °C was less than 1 % while
as temperature increased (20 °C and 25 °C) the losses amounted to 1.9 and 2.9 %,
respectively. Spear quality was preserved in packages at 2.5 °C and 5 °C after 6 days
of storage (Siomos et al. 2000 ).
Green asparagus spears were stored under refrigeration at 2 °C (fi rst treatment),
MAP (OPP P-Plus fi lm was used) at 2 °C (second), and MAP at 10 °C after 5 days
at 2 °C (third) until they were not suitable for consumption. The overall shelf-life
was limited to 9-12, 26 and 14 days for the fi rst, second and third treatment, respec-
tively. Shear force of the basal segment increased during storage in all samples
(70.2, 14.8 and 4.28 % for refrigerated samples, MAP samples at 10 °C and MAP
samples at 2 °C, respectively) (Villanueva et al. 2005 ).
Asparagus spears treated with compressed argon and xenon (Ar/Xe 2/9 v:v)
stored at 4 °C were compared to MAP (A MAP with 5 % O 2 /5 % CO 2 initial atmo-
sphere). MA packed samples had the lowest weight loss (0.5 %) after 18 days of
storage. The use of Ar and Xe blocked the increase in cell permeability compared to
control samples. Due to this effect, respiration peak and crude fi ber formation was
effectively restrained compared to MAP samples (Zhang et al. 2008 ).

ʼ

1.7.6.5 Celery

LDPE and OPP were used to provide MA conditions for storage of celery sticks at
4 °C for 15 days. No signifi cant changes in TSS (3.93 o Brix for both fi lms), TA
(0.089 and 0.091 g citric acid/100 mL for LDPE and OPP) and pH (5.96 and 5.93
for LDPE and OPP) were recorded. The use of both fi lms led to the products with
an acceptable green color at the end of storage whereas samples stored under air
displayed a 10 % decay rate (Gomez and Artes 2005 ).
Several CO 2 contents (0 %, 5 %, 10 %, 20 %, 30 %, 50 %) plus 2 % O 2 were used
to preserve celeriac fl akes at 4 °C and 15 °C (only for 0 %, 5 %, and 10 % CO 2 packs