Pears are harvested mature but not yet ripe, and require a chilling time in cold storage in order to ripen properly at room temperature. Different pear varieties have specific handling and storage regimes, depending on the desired length of storage time needed, and the maturity of the fruit at harvest. The goal is to have fruit that will ripen a few days after consumers purchase them at the market, with excellent fruit quality for eating. Ripening pears is a complex process. Fruit are placed in cold storage immediately after harvest to stop the ripening process, so that fruit can be stored long-term, and available for market on specific dates. The cold temperatures and controlled atmosphere (CA) storage stop the natural ripening process, which inhibits ethylene, a ripening hormone. In order for pears to start the ripening process again, at the proper time for marketing, they need to remain at cold temperatures for a specific amount of time (“chilling requirement”), with or without ripening treatments such as addition of ethylene, and then “conditioned” at warmer temperatures before packing and shipping. There have been challenges in storing winter pears long-term due to their ripening processes and susceptibility to fungal storage rots. Currently scientists at Washington State University (WSU) in cooperation with researchers at Oregon State University (OSU) are studying ripening compounds to use for improved fruit quality. (learn more) For more information related to pear handling and conditioning refer to the USA Pear Handling Manual (conditioning begins on page 21).
Useful Resources and References:
More information specific to handling and storage of pears can be found using the links below. Additional resources can be located using the search box at the top of this page.
- Postharvest Information Network, pear webpage.
- Postharvest Handling and Storage of Pears, article links.
- Pear Handling Manual, USA Pears, Pear Bureau Northwest, 2012. (Accessed: 1/19/17).
WTFRC Research Reports:
- Systems approach for ensuring superior pear fruit quality, D. Sugar and K. Evans, 2013.
- Ripening capacity and decay control in winter pears, D. Sugar, 2014.
- Inheritance of chilling–dependent pear fruit ripening, R. Bell, 2014.
- Pear fruit quality improvement, D. Sugar, 2009.
- Molecular techniques to study apple and pear pathogens in CA storage, S. Stokes, and P. Sholberg, 2005.
Trade Articles on Pear Storage:
- Pear research never ending, M. Hansen, Good Fruit Grower, February, 2014.
- EU regulations stifle fruit exports, M. Hansen, Good Fruit Grower, March, 2012.
- MCP results influenced by temperature, G. Warner, Good Fruit Grower, June, 2012.
- More predictability with MCP needed, G. Warner, Good Fruit Grower, June, 2012.
- Problems with pear ripening, G. Warner, Good Fruit Grower, August, 2011.