During the Winter and Spring New Zealanders will notice an increase in the availability of
apples advertised as CA.
The CA stands for Controlled Atmosphere. This means the fruit has been stored in optimum conditions
in an effort to retain that just picked taste. Fruit and vegetables breathe oxygen and give off
carbon dioxide as part of the natural maturing process. Our fruit is harvested at the optimal time
and taken to high tech sealed CA coolstores.
Timing of harvest is critical to good storage results. By selective picking our apples are perfect
the moment they go into CA storage, and the process holds in that optimum freshness and crunch.
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Energy
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Nitrogen
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Oxygen
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Other CO2
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Temperature
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Normal Air
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78%
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21%
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1%
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Variable 0-30"(dm;
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Controlled Atmosphere
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96%
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2%
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2%
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Constant 0.5"(dm;
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CA virtually halts the fruits natural respiration “breathing” and puts it
in a state of hibernation.
When apples are removed from Controlled Atmosphere the normal life cycle continues. Controlled
Atmosphere Storage means everyone can have superior eating quality apples year round.
Influential Factors in CA
1. The Growing Season
2. Fruit Maturity at Harvest
3. Time Between Orchard and CA Store
4. CA Store Management
5. Natural Storage Life of the Fruit
Not all varieties perform equally well in CA storage. Braeburn, Pacific Rose, Granny Smith and Fuji
keep well until January. Gala strains are at their optimum eating in July and August.
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History of CA
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BC
Egyptians store in limestone crypts
1820
Jacques Etienne Berard professor in France researches effect of atmospheres on fruit ripening
1865
Benjamin Nyce in Cleveland built an air tight store and used ice for cooling.
1918
Kidd & West : Low Temperature Research Station at Cambridge UK
1929
1st commercial use in UK
*see story below
1965
Low Oxygen apple storage (2%)
1994
Yummy Fruit Company first to Supply CA apples NZ Market
* Controlled Amosphere Storage was first used commercially in
England before World War II. Farmers discovered their produce kept longer if stored in airtight
rooms. Apples take in oxygen and give off carbon dioxide as starches in the flesh change to sugar.
In the sealed rooms, this respiratory process reduced the oxygen, thus slowing the ripening
process.
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