PHYSIOLOGICAL STORAGE DECAY ON ORGANICALLY GROWN APPLES PICKED AT DIFFERENT TIMES

The major part of Norwegian apples is marketed within two months after harvest, but because of increasing interest in freshly made juice and supply of locally produced food, storing of apples for a longer time is of increasing interest. The harvest time of apples is known to be important for the development of storage decay and knowledge about the optimal time for harvest of the main cultivar for storage in Norway, 'Aroma', was needed. Apples were harvested weekly in an organic orchard and stored at 4°C, in 2004-2006. The apples were picked 2 and 1 weeks prior to recommended harvest date for short term storage, at the recommended date and 1 or 2 weeks after. They were assessed for quality parameters and amount of storage decay (both physiological and fungal decay) monthly during and at the end of cold storage on February 1 and after two weeks at room temperature (20°C). In 2004 and 2006 the apples from the last picking had significantly more physiological decay than apples picked earlier at the end of cold storage. No significant differences were observed in 2005. Physiological decay after two weeks at 20°C was significantly higher on apples from the last picking in 2004, no difference between harvest times in 2005 and 2006. The amount of physiological storage decay was higher in 2005 than in the other two years. Predominantly, physiological decay was soft scald and internal or senescent breakdown. Physiological decay will be discussed together with fruit quality parameters.