Application of Modified Atmosphere Packaging on Quality of Selected Vegetables: A Review - Application of Modified Atmosphere Packaging on Quality of Selected Vegetables - page 26

Table 1.2 (continued)

Storage temperature
(°C) and storage
period (days)

Shelf
life(days)-Life
extension

Species and
food type

Treatment before
packaging

Texture-
weight loss

Initial gas mix Packaging material Color Microfl ora Sensory analysis References

Irish iceberg
lettuce

Passive MAP:
3-4 % O 2 and
10-12 % CO 2

35 m OPP with OTR:

1,200 mL/m 2 /day/atm. and
CO 2 TR: 4,000 mL/m 2 /day/
atm.

ʼ Inoculation with L.

monocytogenes and two
nontoxigenic E. coli
O157 : H7 strains

4 and
8 °C—12 days

Pathogens
populations
increased (1.5 to 2.5
log CFU/g) on
samples stored at
8 °C while during
storage at 4 °C
microbial load
remained close to
their initial numbers

L.
monocytogenes
and E. coli
O157 : H7
populations
were reduced by
reducing
storage
temperature
from 8 to 4 °C

Francis and
O'Beirne ( 2001 )

Irish iceberg
lettuce

Inoculation with 4 strains
of L. monocytogenes with
or without genes for
glutamase decarboxylase
resistance mechanism

4, 8 and 15 °C The wild type L.

monocytogenes
strain displayed
higher survival rates
compared to double
mutant ʔ gadAB

Francis et al.
( 2007 )

Irish
butterhead and
iceberg lettuce

AMAP was
created by N 2
fl ush prior to
packaging

OPP 35 ʼ m Lettuce was:

1. Hand torn
2. Cut with blunt knife
3. Cut with razor blade
and inoculated with E.
coli and L. innocua strains

8 °C for 9 days For butterhead

lettuce razor sliced
samples had
signifi cantly lower
L. innocua numbers
(by 1.2 log CFU/g)
compared to hand
torn ones or the
samples cut with a
blunt knife. On
iceberg lettuce
populations on
razor sliced samples
were higher
compared to the
other two

Mild processing
techniques such
as hand tearing
or the use of a
razor blade can
result in
reduced survival
and growth of
E. coli and L.
innocua

Gleeson and
O'Beirne ( 2005 )