Mechanical damage of ‘Huangguan’ pear using different packaging under random vibration

Abstract

The mechanical damage of fresh fruit under random vibration during postharvest transportation is a major problem in agricultural industry. This paper investigated the mechanical damage of ‘Huangguan’ pear (Pyrus bretschneideri Rehd. ‘Huangguan’) under random vibration excitation considering package type, vibration level, and vibration duration. Limited white noise with the frequency 3 Hz – 80 Hz was used as the excitation spectrum. Results showed: vibration results in the obvious decline of pear firmness. Firmness of pears with five package types after vibration decreased 9 % to 26 %. Package type had a great effect on the mechanical damage of pears. The package type of expanded polystyrene (EPS) tray + expandable polyethylene (EPE) net cover can provide the best cushioning effect for pears. The response vibrations of pears are related to positions. The resonant frequencies of stacked pears were concentrated in the range of 23 Hz–56 Hz. Response vibrations of pears in the corner were more severe compared with the pears in the center. In addition, the damage rules of pears with the package type of corrugated paperboard division + paper wrapping under different vibration levels and durations were revealed. The relationships of damage area and vibration level, firmness and vibration level, damage area and vibration duration conformed to linear correlation. Exponential function can be used to describe the relationships of damage volume and acceleration level, damage volume and vibration duration, firmness and vibration duration. This study provides references for vibration resistant packaging design of fruit, and thus to minimize the mechanical damage of fruit in supply chain.