Comparison of physiochemical characteristics of Citrus reticulata cv. Shatangju fruit with different fruit sizes after storage

'Shatangju' (Citrus reticulata) is a loose-skin mandarin cultivar with delicious taste quality. However, its fruit size varied greatly which might affect the storage results. This study investigated the physiochemical characteristics of 'Shatangju' fruit with different sizes after a long-term storage, and found that small fruit tended to have a longer shelf life. According to the results, the fruit with a higher transverse diameter tended to contain more seeds and had lower edible rate. The storability of 'Shatangju' fruit decreased with the increase of fruit size, in that the big fruit suffered more severe vesicle collapse after storage. Correspondingly, the physiochemical characteristics of the flesh varied among stored fruit of different sizes. The stored larger fruit tended to have higher content of cellulose, hemicellulose and lignin, as well as a lower content of soluble sugars, organic acids, and amino acids in the flesh, which led to the bad texture and tasteless flavor. We also found that the vesicle collapse of 'Shatangju' fruit was a very complicated syndrome involving a series of physiochemical changes rather than simple water loss. The results of the present study provided guidance for the classification and storage of 'Shatangju' fruit after harvest.