Why is predicting kiwifruit quality in the cool chain so difficult?

To enable year round supply of seasonal products, such as kiwifruit, a portion of the harvested volume is cold stored. For kiwifruit, despite best efforts, a proportion of this cool stored stock’s quality diminishes to a point of being unsaleable resulting in fruit loss. Predicting the rate and extent of quality loss during storage in theory should be predictable based on knowledge of the at-harvest condition and time-temperature history of the stock, and applying a time-temperature-tolerance hypothesis. Unfortunately this has not proven to be the case with a number of factors contributing to proliferation of variability in the cool chain. This paper discusses evidential data for additional prediction complications introduced by grower line differences, cooling rate, storage temperature and ethylene concentration. Only when each of these effects can be measured and described will kiwifruit quality be able to be adequately predicted and hence industry storage losses reduced.