In one test comparing watercored fruit harvested on October 20 and on October 30, apples picked on the earlier date no longer had scorable watercore after 180 days in storage, but those from the second harvest still had a lot of watercore. There was a large amount of internal injury at all oxygen levels. In some cases, the browning had moved out from the watercored area seen at harvest into the outer flesh and also formed cavities. Even after only 90 days in storage, there was some internal breakdown, particularly in fruit from the second harvest. Although this can be mitigated by storing the fruit in oxygen levels of up to five percent, the higher oxygen level reduces the chances of successfully storing the fruit in CA in terms of other quality attributes, such as firmness.
Fruit stored at higher oxygen levels also loses more acidity.
Mattheis said there's good potential for storing Fuji apples at higher oxygen levels for shorter periods. Mattheis said more research needs to be done on storage temperatures.