Storage and shelf-life of apples grown in Norway - II. Effects of controlled atmosphere storage on 'Summerred'

Apples of the cultivar 'Summerred', grown in Norway (59 degrees 40'N), were harvested in September and stored in controlled atmosphere (CA) at 3 % O-2 + 3 % CO2 or in normal air (NA) at 2 degreesC until the middle of January. After removal from storage in December and January, the apples were kept o ne week at room temperature, simulating shelf-life. There were only small o r no differences in fruit quality between the two storage methods. Principa l component analysis (PCA) of shelf-life samples revealed three components explaining 87 % of the total variation. The most important cause of variati on were the storage methods (41% explained), followed by storage period (31 % explained) and the variation caused by year of harvest (15 % explained). Beneficial effects of CA-storage for 'Summerred'-apples were of minor impor tance and therefore they cannot justify the cost of CA-storage.