Prestorage conditioning, diphenylamine improve condition of 'honeycrisp' apple
Tuesday, April 22, 2014
Scientists determine methods for improving resistance to controlled-atmosphere-related injury
EAST LANSING, MI--Since the introduction of 'Honeycrisp' apples in
1991, the variety has become a consumer favorite for its unusual texture
and delicious flavor. Honeycrisp has increased in popularity with
growers as well; Michigan, New York, and Washington boast significant
numbers of 'Honeycrisp' orchards. As the growing area dedicated to the
variety has grown, the need to find better methods for improving storage
performance has become more important to growers. Because 'Honeycrisp'
is very sensitive to low temperatures and can be damaged by
controlled-atmosphere conditions, long-term storage of the apples can be
Carolina Contreras and Randy Beaudry from the Department of
Horticulture at Michigan State University and Nihad Alsmairat from the
Department of Horticulture and Crop Science at the University of Jordan
published a study in HortScience that revealed some important
information for apple producers. "Our work was conducted in two phases,"
Beaudry explained. "The first phase was designed to determine whether
'Honeycrisp' apples were susceptible to controlled-atmosphere injury, to
determine the relative influence of O2 and CO2,
and to identify a treatment combination that would reliably generate
symptoms so that control measures could be subsequently evaluated." In
the second phase, the scientists evaluated options for avoiding injury
to 'Honeycrisp' during controlled-atmosphere storage. Fruit were
conditioned at 3º C, 10º C, and 20º C for 5 days and then exposed to one
of nine different storage treatments.
In the first experiment, 'Honeycrisp' exhibited a high sensitivity to both low oxygen and elevated CO2 levels. "We found that the controlled-atmospheres used induced injuries typical of those associated with CO2
(i.e., small brown lesions and associated lens-shaped cavities) and
also larger dark brown lesions with often irregular margins," the
authors said. "The extent of the injury was higher for those fruit in an
atmosphere with elevated CO2 for each level of O2."
Subsequent experiments took place over 3 years, during which the
researchers reproduced the controlled-atmosphere (CA) injury from the
preliminary study with varied intensity. Although the researchers
observed high variability between orchards and years, they found two
treatments that effectively controlled the CA injury. "We found that
the brown lesions in the cortex were completely suppressed by DPA
application, even when the prestorage conditioning temperature was 3º
C," Beaudry said. "The incidence of cavities ranged from 0.1% to 0.3%
under the same DPA treatment. On the other hand, the most affected
treatment was 3/3 followed by 3/0, 21/0, and 21/ 0 plus 1-MCP."
The authors noted that, while there is good progress toward
determining optimal storage recommendations for 'Honeycrisp' additional
studies are still warranted. "For instance, although the 7-day
prestorage conditioning treatments provided some protection against the
development of CA injury, shorter durations should be investigated to
prevent quality loss resulting from excessive ripening, which could
cause increased skin greasiness and undesirable flavor profile."
The study includes additional recommendations for handling 'Honeycrisp' in prestorage conditions.
The complete study and abstract are available on the ASHS HortScience electronic journal web site: http://hortsci.ashspublications.org/content/49/1/76.abstract
Founded in 1903, the American Society for Horticultural Science
(ASHS) is the largest organization dedicated to advancing all facets of
horticultural research, education, and application. More information at ashs.org
This press release also available on EurekAlert! - view here
Prestorage Conditioning and Diphenylamine Improve Resistance to Controlled-atmosphere-related Injury in 'Honeycrisp' Apples
Carolina Contreras, Nihad Alsmairat, and Randy Beaudry
HortScience 49:76-81. [Abstract]
Corresponding author. E-mail: firstname.lastname@example.org