Best Way to Store Fresh Fruits and Vegetables
The majority of Australian fruits and vegetables must be consumed within weeks of harvest as they have limited storage life.
Some examples are: apricot, asparagus, banana, berry fruits, broccoli, brussel sprouts, cauliflower, cucumber, eggplant, leafy greens, mango, nectarine, pawpaw, pea, peach, pineapple, plum, quince, rhubarb, silverbeet, sweet corn, tomatoes and zucchini.
A very few fresh produce lines can be stored for months before sale.
There are two main methods used to extend the longevity and quality of certain produce lines – controlled atmosphere and curing.
(a) Controlled Atmosphere (CA) is storage method used to extend the life of fresh produce. The air (with reduced oxygen) and temperature surrounding the stored produce is controlled resulting in the produce being put to ‘sleep’. In this state the produce’s life is maintained and the rate of internal breakdown is reduced.
CA allows the quality of the produce to be maintained, as well as making it available throughout the year. There is minimal decline in nutritional value. Some produce lines stored using CA are: apples, pears, and to a lesser extent grapes and green lemons.
(b) Curing is a simple, effective and natural way to extend the longevity of some root crops. These crops can be simply stored for months in a dry area with good airflow. Curing is applied to crops such as cassava, French eschallots, garlic, ginger, horseradish, mature carrots, onions, parsnip, pumpkin, swede, sweet potato, turnips and yams. In practice, however, these produce lines are not usually stored for very long periods.
Ripening and protecting fresh produce.
(a) Controlled Ripening with ethylene gas, a natural gas given off by fruit and vegetables as they ripen. The ethylene is used to ensure more uniform ripening prior to retail distribution. Controlled ripening is used primarily for bananas. It may be used for avocado, tomatoes, pears, pawpaw, plums, and in the de-greening of early Navel and late Valencia oranges.
(b) Waxing is used to reduce water loss, increase shelf-life, reduce breakdown and to enhance presentation. Wax is applied to the produce before storage or entry into the marketing/retail chain. Most waxes are derived from natural ingredients and waxed products must be labelled in accordance with the Australian Foods Standards Code. Waxing is mainly used on apples.
Prepared for the NSW Chamber of Fruit and Vegetable Industries Inc by:
Lawrie Greenup BSc Agr, MSc, Dip Env Stud Consultant to the Fresh Produce Industry