Extension of postharvest life of oyster mushroom under ambient conditions by modified atmosphere packaging.
Jayathunge, K. G. L. R. Illeperuma, C. K.
Tropical Agricultural Research 13:78-89.
2001
บทคัดย่อ
Suitability of polypropylene, low-density polyethylene, linear low-density polyethylene (LLDPE) as a packaging material and effectiveness of 0.5% calcium chloride and 0.5% citric acid (CA) as a washing treatment were tested based on off-colour and off-odour development in mushroom (Pleurotus). A suitable package surface area to weight ratio was also established. Effectiveness of magnesium oxide in modifying the in-package gaseous atmosphere and thereby, extending the postharvest life was tested by monitoring the concentrations of oxygen, carbon dioxide, acetaldehyde, ethanol, weight loss and the 'L' value of oyster mushroom during storage for 6 days at 27 plus or minus 2 deg C and 82 plus or minus 3% RH. The developed modified atmosphere packaging system was compared with a commercial package. Oxygen concentrations were 2.6, 3.8, 7.6 and 9.5% in the control and packages containing 1, 3 and 5 g of magnesium oxide, respectively, on day 4 in storage. Under similar conditions, carbon dioxide concentrations were 12.7, 7.9, 3.5 and 1.7%, respectively. Ethanol contents in the control and mushroom packaged with 1 and 3 g of magnesium oxide were 210, 126 and 103 ppm and acetaldehyde contents were 43, 19 and 10 ppm, respectively on day 4 in storage. Washing of oyster mushroom with 0.5% calcium chloride and 0.5% CA followed by packaging in 0.015 mm LLDPE in a 3 : 1 surface area to weight ratio with 3 g of magnesium oxide as a carbon dioxide scavenger was successful in extending the shelf life up to 5 days at 27 plus or minus 2 deg C and 82 plus or minus 3% RH. Shelf life of the commercial sample was 2 days.