Drop impact dynamic characteristics and relationship between its characteristics and firmness for peach

In recent years, there is an increasing demand for the quality of all kinds of fruits, and considerable researches on the measurement of quality of fruits have been carried out. This research is focused on the characteristics of frequency-spectrum of peach under lower height, and the correlation between response frequency and physical property parameters. The peach dynamic resonance frequencies were obtained based on the analysis of the dynamically measured frequency response of peaches drop onto plate with the drop height, the peach firmness, the peach mass and the storage day. As a result of the analysis, the dominant resonance frequencies (the response magnitude was the greatest) could be obtained and they were significantly affected by the storage days, the peach firmness, the peach mass. The drop height did not significantly affect the dominant frequency. The dominant frequency increased with the peach firmness increasing, and the dominant frequency decreased with increasing of the peach mass. The better relationship was obtained between the dominant frequency and the peach firmness or the peach mass, and the stiffness coefficient regressed on Magness-Taylor firmness had a good relationship. The peach firmness can be predicted by drop impacting method.