บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Softening characteristics of Chinese pear 'Yali' fruit with special relation to changes in cell-wall polysaccharides and their degrading enzymes.

Ning, B.; Kubo, Y.; Inaba, A.; Nakamura, R.;

Scientific Reports of the Faculty of Agriculture, Okayama University Year: 1997 Issue: No. 86 Pages: 71-78 Ref: 21 ref.

1997

บทคัดย่อ

Softening characteristics of Chinese pear 'Yali' fruit with special relation to changes in cell-wall polysaccharides and their degrading enzymes.

The softening characteristics of Chinese pear cv. Yali [Pyrus bretschneideri] fruits, based on changes in the rates of respiration and ethylene production, flesh hardness, the content of cell-wall polysaccharides and the activities of their degrading enzymes were determined, in comparison with Japanese pear cv. Nijisseiki [P. pyrifolia] and European pears La France and Bartlett [P. communis]. Rates of respiration and ethylene production in Yali, La France and Bartlett fruits increased with the advance of ripening, the most significant increase of ethylene production being shown by Yali fruits. Decrease of flesh hardness during ripening was rapid in La France and Bartlett fruits, but slow in Yali and Nijisseiki fruits. Although rapid increase of pectin methylesterase activity in La France and Bartlett fruits was observed with a concomitant decrease of flesh hardness, the activity was maintained at a lower level in Yali and Nijisseiki fruits. Increase in polygalacturonase activity during ripening

was rapid in La France and Bartlett fruits, but slight in Yali and Nijisseiki fruits. Cellulase activity increased with the decrease in flesh hardness in La France and Yali fruits, whereas its increase was slight during ripening in Nijisseiki and Bartlett fruits. Increase in the content of water-soluble pectin and decrease in the content of hydrochloride-soluble pectin during flesh softening were very slight in Yali and Nijisseiki fruits in contrast with La France and Bartlett fruits. From the results obtained, it appears that maintenance of long-term hardness in Yali fruits during ripening is due to lower activities of enzymes responsible for degrading cell-wall polysaccharides, compared with those in other pear fruits.