Effects of Vibration Stress on the Quality of Packaged Apples during Simulated Transport

Purpose: The characteristics of in-transit vibration stress and possible damage to packaged apples were examined. Methods: A simulated transportation environment with a specific power density profile was used for vibration impact experiments to determine the resulting decrease in packaged apple quality. Apples with or without vibration stress were stored at low temperature (<TEX>5±0.8∘C</TEX>, 75-85% relative humidity) for 30 days. Statistically significant differences (p <TEX>≤</TEX> 0.05) were found between apples with and without vibration stress for concentration of oxygen (<TEX>O₂</TEX>; 11.2% and 14.1%, respectively; initially <TEX>29±0.4%</TEX>), carbon dioxide (<TEX>CO₂</TEX>; 26.4% and 21.8%; initially <TEX>1±0.2%</TEX>), and ethylene (79.4 <TEX>μLL⁻¹</TEX> and 55.6 <TEX>μLL⁻¹</TEX>; initially <TEX>14.1±0.6μLL⁻¹</TEX>) in the headspace of a gas-collecting container after 30 days of storage. Results: Significant differences were also measured for apples with and without vibration stress with respect to soluble solid content (15.4% and 14.9%, respectively; initially <TEX>12.9±0.8%</TEX> and <TEX>13.1±1.1%</TEX>), weight loss (10.1% and 8.2%), and firmness (139.7 kPa and 163.3 kPa; initially <TEX>213.8±6.2</TEX> kPa and <TEX>209.1±7.9</TEX> kPa) after 30 days of storage. Conclusions: The vibration stress clearly accelerated the degradation of apple quality during storage, resulting in increased weight loss, soluble solid content, and headspace <TEX>CO₂</TEX> and ethylene production, and decreased firmness and headspace <TEX>O₂</TEX>.