Project/Area Number |
07556012
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 試験 |
Research Field |
園芸・造園学
|
Research Institution | Hiroshima University |
Principal Investigator |
SAKURAI Naoki Hiroshima University Professor Faculty of Integrated Arts and Sciences, 総合科学部, 教授 (90136010)
|
Co-Investigator(Kenkyū-buntansha) |
WADA Naoki Matsushita-Kotobuki Engineer Electronics Industries Ltd., 開発研究所, 技師
YAMAMOTO Ryoichi Tedukayama College Professor, 食品, 教授 (10047384)
|
Project Period (FY) |
1995 – 1996
|
Project Status |
Completed (Fiscal Year 1996)
|
Budget Amount *help |
¥5,300,000 (Direct Cost: ¥5,300,000)
Fiscal Year 1996: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1995: ¥3,500,000 (Direct Cost: ¥3,500,000)
|
Keywords | Fruit softening / cell walls / viscoelastic proterty / acoustic wave / laser beam / Doppler effect / ethylene / stress-relaxation |
Research Abstract |
The following results were obtained ; (1) When kiwi fruit was vibrated, the Doppler shift of laser beam reflecting from the surface of the fruit was precisely determined by a laser Doppler vibrometer. (2) Amplitude of the vibration of fruit was monitored from 5 to 2000Hz, and several resonance peaks were detected. The resonance frequency decreased when an apple fruit was soften, as reported, but the decrease was not observed in other fruits, suggesting that the resonance frequency is not the best index for the fruit softening. (3) The shift of acoustic waves was observed, when the fruit proceeds softening. There was a good correlation between the phase shift and fruit softening in peach, pear, and citrus orange. (4) The phase shift reflects the inside organization of citrus fruit. (5) The differential signal between an accelerometer attached to the stage of vibrometer and the laser Doppler measuring machine tells the precise vibration signal derived from the test fruit. From these results, the fruit softening measurement system using a laser beam is superior to any other reported method, and is an excellent remote and non-destructive method to evaluate qualitatively and quantitatively the degree of fruit softening. Although we could not produce a prototype of fruit sorting machine, the algorism for evaluating the fruit texture is still being processed in Matsushita-Kotobuki Electronics Industries Ltd.
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