The effect of fruit maturity and storage duration on friction discolouration of Packham's Triumph and Doyenne du Comice pears
Date
2005-04
Authors
Burger, G. E.
Griessel, H. M.
Huysamer, M.
Journal Title
Journal ISSN
Volume Title
Publisher
International Society for Horticultural Science -- ISHS
Abstract
Friction discolouration (FD) is causing the South African pear industry
multi-million rand losses due to blemished fruit being rejected for the export market
and being sold locally. The occurrence of FD was studied over two seasons using
‘Packham’s Triumph’ and ‘Doyenne du Comice’ (Pyrus communis) fruit. The
influence of fruit maturity and storage duration were investigated by harvesting
over three maturities and storing fruit for up to three months. FD was induced using
a modified laboratory shaker that was shown to closely mimic pack line damage.
Polyphenol oxidase (PPO) activity and total phenolics (TP) content were also
evaluated. ‘Doyenne du Comice’ was more prone to FD than ‘Packham’s Triumph’.
Harvest maturity significantly influenced FD susceptibility, with the middle picking
maturity generally giving higher FD ratings. Increasing storage duration generally
increased FD ratings, although not consistently. PPO activity was not influenced by
harvest maturity, but was influenced by storage duration. In ‘Packham’s Triumph’,
the TP content was not affected by harvest maturity or storage duration, whereas
both these factors significantly influenced TP content in ‘Doyenne du Comice’.
Susceptibility to development of FD symptoms is not easily linked to either PPO
activity or TP content, and seasonal differences in susceptibility make prediction of
possible levels of FD very difficult.
Description
The original publication is available at http://www.actahort.org/books/671/671_53.htm
Keywords
Pyrus communis (Pears) -- Quality, Impact recording device, Fruit (Pears) -- Postharvest technology, Fruit (Pears) -- Diseases and injuries
Citation
Burger, G. E., Griessel, H. M. & Huysamer, M. 2005. The effect of fruit maturity and storage duration on friction discoulouration of 'Packham's Triumph' and 'Doyenne du Comic'e pears. Acta Hort. (ISHS) 671:377-384.