Studies explore storage ideas for Anjou pears

Jan 31, 2014 by Marcia Wood
A technology for detecting problems in stored apples turns out not to work well as an early warning system for Anjou pears kept in very-low-oxygen storage, ARS research shows. Credit: Doug Wilson

Fresh Anjou pears, harvested in late summer from orchards in Oregon and Washington, will usually be available in supermarket produce departments through early spring of the following year. That's thanks to, in part, science-based, long-term-storage technologies that help postpone ripening.

In ongoing studies, U.S. Department of Agriculture (USDA) researcher James P. Mattheis and his colleagues are tackling some of the problems that may affect this popular pear while or after it has been kept in refrigerated, low-oxygen storage, also referred to as controlled-atmosphere storage.

Some of this research suggests that tactics that work well for keeping fresh apples free of plant diseases or other disorders while in controlled-atmosphere storage may not necessarily be quickly or easily applied to meet Anjou pears' storage needs.

In one early study, Mattheis and coinvestigator David R. Rudell, Jr., both with the USDA Agricultural Research Service (ARS) Tree Fruit Research Laboratory at Wenatchee, Wash., and former postdoctoral research associate David Felicetti, tested chlorophyll fluorescence monitoring as a candidate "early warning system" for keeping an eye on the quality of stored pears.

According to Mattheis, the technology is used successfully to detect problems in stored apples. That's because an increase in the fluorescence levels in the chlorophyll in a stored apple's peel apparently correlates well with an increase in problems linked to low oxygen levels.

When apple chlorophyll levels go up during storage, storehouse managers know to raise the oxygen level slightly to prevent damage to the fruit.

But the Anjou research, documented in scientific articles in Postharvest Biology and Technology in 2011 and 2013, showed that the monitoring system didn't work well in detecting either black speck or pithy brown core in Anjou pears that were stored, experimentally, in extremely low oxygen conditions.

The scientists found that black speck and pithy brown core occurred despite the fact that there were no detectable changes in the affected pears' chlorophyll fluorescence levels. For that reason, Mattheis is—for now—advising packers to use caution before relying on chlorophyll fluorescence for monitoring stored Anjou pears in very low oxygen conditions.

Black speck is an unwanted speckling of the pear's skin; pithy brown core, as its name implies, discolors the pear near its core and changes the pear's texture from delectable to unpleasantly fibrous.

This and related ARS-led Anjou pear research at Wenatchee is described in the January 2014 issue of Agricultural Research magazine. ARS is the USDA's chief intramural scientific research agency.

Explore further: Catfish industry embraces USDA pond management research

add to favorites email to friend print save as pdf

Related Stories

Enhanced lure proves irresistible to orchard pest

Jul 08, 2013

New lures that entice codling moths with the scent of food and a possible mate are available for use in monitoring this orchard pest and controlling it with carefully timed applications of insecticide. The ...

Ripe Fruit Preferred

Nov 05, 2007

Fall, the season of colors: Leaves turn red, yellow, and brown. The disappearance of the color green and the simultaneous appearance of these other colors are also signs of ripening fruit.

Recommended for you

France fights back Asian hornet invader

2 hours ago

They slipped into southwest France 10 years ago in a pottery shipment from China and have since invaded more than half the country, which is fighting back with drones, poisoned rods and even chickens.

Tide turns for shark fin in China

2 hours ago

A sprawling market floor in Guangzhou was once a prime location for shark fin, one of China's most expensive delicacies. But now it lies deserted, thanks to a ban from official banquet tables and a celebrity-driven ...

Manatees could lose their endangered species status

15 hours ago

About 2,500 manatees have perished in Florida over the last four years, heightening tension between conservationists and property owners as federal officials prepare to decide whether to down-list the creature to threatened ...

User comments : 0