Application of Modified Atmosphere Packaging on Quality of Selected Vegetables: A Review - Application of Modified Atmosphere Packaging on Quality of Selected Vegetables - page 52

1.7.6 Stems and Shoots

1.7.6.1 Kohlrabi

Escalona et al. ( 2007a ) studied the effect of passive MAP (with OPP and amide PE
fi lms used after washing in a NaOCl water solution) to preserve kohlrabi sticks at
0 °C for 14 days. Kohlrabi reached a very low C 2 H 4 release of 5-10 nL C 2 H 4 /kg/h
from the beginning till the end of storage. The L *, a *, b *, and chroma parameters
decreased after 7 days at in all treatments (36.3, 36.1, 36.5, for L *, −2.5, −2.6, −2.4
for a *, 2.4, 2.3, 1.8 for b * and 3.5, 3.5 and 3 for chroma control, OPP and Amide PE
samples respectively, after 14 days of storage). The sticks stored under MAP condi-
tions scored above the limit of marketability for organoleptic attributes on the 14th
day of storage.
Kohlrabi stems were stored under MAP (with OPP and Amide-PE and washed in
a NaOCl water solution) for 60 days at 0 °C, while an additional retail sale period
of 3 days at 12 °C after each cold storage evaluation (30 and 60 days) was applied.
A minor yellowing representing lower hue value on the skin after 60 + 3 days
appeared on the MAP kohlrabi stems. The weight loss on control stems from day 30
to 60, as indicated by Escalona et al. ( 2007b ) for amide-PE and OPP were 0.24, 0.31
and 0.1 %, respectively.
Passive MAP (OPP 20

m, and amide polyethylene fi lms) applied
on stored kohlrabi stems at 0 °C for 14 days and at 10 °C for 3 days was monitored
by Escalona et al. ( 2007c ). The ethylene production was higher than 0.05

ʼ m, OPP 40 ʼ

L/kg/h
throughout storage. The citric acid content (79.3 mg/100 mL at harvest) did not
display any signifi cant changes (64.8, 73, 72.2 mg/100 mL for OPP 20 , OPP 40 and
amide-PE, respectively). Although the appearance and texture of kohlrabi deterio-
rated compared to values at harvest, the scores were maintained throughout the
retail sale period.

ʼ

1.7.6.2 Bamboo Shoots

An effort was made to prolong the shelf life of bamboo shoots by applying MAP
(LDPE fi lm with initial atmosphere of 2 % O 2 and 5 % CO 2 ) on bamboo shoots
stored at 10 °C by Shen and his co-workers ( 2006 ). A browning process began in the
bamboo shoots of MAP treatment at the sixth day and their browning index reached
1.2 on day 10. MAP treatment inhibited the activity of POD (32 with 55 u/min g FW
for the control samples) and PAL (1.25 with 2.0 nmol/h g FW for the control
samples).