Storage methods for extending shelf life of fresh, edible bamboo shoots [Bambusa oldhamii (Munro)]
V. Kleinhenz, M. Gosbee, S. Elsmore, T. W. Lyall, K. Blackburn, K. Harrower and D. J. Midmore
Postharvest Biology and Technology Vol: 19 Issue: 3 Pages: 253-264.
2000
บทคัดย่อ
Fresh bamboo [Bambusa oldhamii (Munro)] shoots were harvested, and
stored in the open or packaged in a range of materials at different
temperatures (1, 2, 8, 11, 20, 25°C) to determine their shelf
life under various storage conditions. Shelflife could be extended by primarily
reducing storage temperature and secondarily packaging bamboo shoots. Under
traditional storage at ambient temperature (20¯25°C)
without packaging, high transpirational weight loss (22.6±0.5%
of initial fresh weight after 6 days storage duration) limited shelf life of
bamboo shoots to 1 day. When water loss was reduced to 2.2±0.1%
of initial fresh weight by enclosing shoots in low-density polyethylene (LDPE)
film, shelf life was extended to 6 days. Under those conditions, respiration
(2.97±0.22
mmol CO2 kg-1 h-1) accounted for a larger
percentage of total weight loss (35% after 6 days) and a Q10
of 2.3 for respiration between 20 and 2°C stressed the need to
quickly cool bamboo shoots after harvest and reduce storage temperatures. At
temperatures above 1¯2°C (i.e. 8°C),
discoloration and fungal growth reduced shelf life of bamboo shoots to not more
than 10 days. Microbial decay appeared to be the primary cause for this
deterioration in quality since bacterial, fungal and coliform microorganisms
were present on external surfaces and internal tissues of shoots. At 1¯2°C,
respiration (about 0.7 mmol CO2 kg-1 h-1) was
low and, therefore, transpiration accounted for up to 94% of total weight loss.
Shelf life at these low storage temperatures was affected by weight loss and
decline in visual packaging quality. Weight loss from packages was greater in
the more permeable materials, e.g. the shelf life of shoots in macro-perforated
LDPE bags (8.9% area perforated) was reduced to 17 days. In contrast,
accumulation of condensate in low-permeable materials (LDPE bags and
particularly heat-sealed PVC film) reduced shelf life to 21 and 14 days due to
loss of visual packaging quality. The most suitable packaging materials were
thin, micro-perforated (45 
m,
0.01% perforation) LDPE bags and non-perforated LDPE film (10.5 m
thick). This reduced total weight loss of bamboo shoots to about 5% after 28
days, minimized condensation within packages and extended shelf life to, and
probably beyond 28 days.