‘Gem’ pear is a relatively new European pear cultivar with good fire blight resistance. Fruit can be eaten without ripening, either at harvest or upon removing from cold storage, when still crisp and juicy, or can be expected to ripen to a buttery melting texture after 30-60 days of regular-air (RA) storage (~30 °F). Although research initially indicated ‘Gem’ could be stored in RA conditions for 5 months with good quality retention, in practice ‘Gem’ storage has proved more challenging, primarily due to internal breakdown which can appear as early as 2 months after storage, either in RA or controlled atmosphere (CA) conditions. Additionally, with increasing commercial production of ‘Gem’, there is industry interest in extending storage beyond 5 months. This on-going study evaluates factors potentially influencing internal breakdown development, such as cooling delay (representing a delay of room temperature establishment at storage facility) and fruit maturity in year 1 and cooling delay and rate of controlled atmosphere (CA) establishment in year 2. In year 1, internal breakdown incidence was essentially absent for fruit harvested at 56 N flesh firmness but higher for fruit harvested at 44 N, especially where cooling was delayed. Fruit harvested at 56 N did not soften to below 18 N at 60 d storage, indicating a longer period of postharvest chilling is required for less mature fruit.
