Abstract:
Modified atmosphere packaging depleted in O2
and enriched in CO2
used in conjunction with refrigeration may provide an effective means of retarding deterioration, maintaining quality and extending the postharvest life of avocados. Mature
pre-climacteric avocados (cv. Fuerte) were packaged in a range of plastic films and
stored at temperatures of 4, 7 and 10°C. The treated fruits along with the controls
were ripened at 20±0.5°C and the relative humidity of 90-95%. Optimum storage
duration, fruit injury and weight loss were determined during storage and ripening
of fruits. In packs sealed with the micro-pores film MY-15, the O2
concentration
decreased to 4.0-6.5% and the CO2
increased to 6.5-11.0% during storage. Fruits
sealed in polyethylene packs were stored well up to 28 days at 4°C and 35 days at
7°C without chilling injury whereas the air stored fruits showed chilling injury after
21 and 28 days of storage at both temperatures, respectively. Modified atmosphere
plays a significant role in retaining vitamin C, total sugars, oil, pH and flesh firmness
of the fruit during storage. Modified atmospheres tended to cause an increase in the
amount of palmitic and palmitoleic acids and decrease in the percentage of oleic,
linoleic and linolenic acids. Among the tested films, low density polyethylene and
micro-perforated film MY-15 and MD-15 were found to be suitable in extending the
shelf life of avocados at low temperatures. Best results were obtained using microperforated film MY-15 and the fruits stored well for six weeks in modified atmospheric conditions with 4.8% O2 + 8.4% CO2 at 7°C. Commercial application of these
packaging techniques would help to maintain the quality of avocados throughout
the distribution and marketing chain.
