Mechanical damage, particularly bruising, is a major cause of postharvest losses in fresh produce, significantly impacting fruit quality and marketability. Apples, being highly susceptible, experience external forces during handling, storage, and transportation, primarily from vibrations, impacts, and compression. This study analyzes the effects of vibration parameters (intensity and duration), truck suspension systems, apple varieties, and packaging configurations on minimizing apple bruising under realistic transportation conditions. Two apple varieties, Fuji and Jonagold, were packaged in corrugated boxes with trays, reusable plastic containers (RPCs) with trays, and volume packing systems. They were exposed to random vibration profiles based on ASTM D4169, simulating leaf-spring and air-ride suspensions at intensities 0.2, 0.3, 0.5 and 0.7 Gravity Root Mean Square (Grms) for 1, 3, and 5 hours. Additionally, a multi-layer packaging setup was tested to evaluate damage distribution across layers. Results demonstrated that vibration intensity, duration, and suspension type significantly influence bruising. Leaf-spring suspensions caused more damage than air-ride systems, especially at higher intensities and longer durations. Apples in the top layer of stacked packages experienced the most damage, while lower layers benefited from load distribution. Among packaging types, corrugated board with Hexcel wrap outperformed others, offering improved protection and recyclability. To further assess factor importance, Random Forest Regression was applied, revealing vibration intensity as the most influential factor, followed by duration, packaging type, and apple variety. These findings support the need for optimized packaging and vibration control strategies. This study highlights the importance of combining vibration testing, sustainable packaging materials, and multi-layer designs to reduce apple bruising. It also suggests the development of new ASTM/ISTA test profiles tailored to produce distribution, including multi-axis vibration testing for improved simulation accuracy.
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