Kiwifruit chilling injury (CI) damage occurs after long-term exposure to low temperature. A non-destructive approach to detect CI injury was tested in the present study, using a laser backscattering image (LBI) technique calibrated with 56 liquid phantoms for providing absorption coefficient (µ_a) and reduced scattering coefficient (µ_s’). Calibration of LBI resulted in a true-positive (TP) classification of 91.5% and 65.6% of predicted µ_s’ and µ_a, respectively. The optical properties of ‘SunGold™’and ‘Hayward’ kiwifruit were analysed at 520 nm with a two-step protocol capturing pre-classification according to the LBI parameters used in the calibration and estimation with the Farrell equation. Severely injured kiwifruit showed white corky tissue and water soaking, reduced soluble solids content and firmness measured destructively. Non-destructive classification results for ‘SunGold™’ showed a high percentage of TP for severe CI of 92% and 75% using LBI parameters directly and predicted µ_a and µ_s’ after pre-classification, respectively. The classification accuracy for severe CI ‘Hayward’ kiwifruit with LBI parameter was low (58%) and with µ_a and µ_s’ decreased further (35%), which was assumed to be due to interference caused by the long trichomes on the fruit surface.

In this study, the physiological indicators, reactive oxygen species (ROS) levels, and activities and expressions of key enzymes related to ROS metabolism were monitored to explore the mechanism of ozone treatment on the shelf life of postharvest Korla fragrant pears. The results show that postharvest fragrant pears treated with ozone had a higher firmness and lower weight loss rate and decay rate during their shelf life, especially in the late stage. Ozone treatment could also delay the occurrence of the respiratory peak and reduce the peak value. The generation rate of superoxide anion (O₂⁻), the hydrogen peroxide (H₂O₂) content, and the malondialdehyde (MDA) level were reduced in the ozone-treated group, while the activities of key enzymes, superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), related to ROS metabolism in postharvest fragrant pears were stimulated by ozone treatment, especially in the middle and late stages of shelf life. Analysis of the proteomics results indicates that the POD family enzymes were the main target protein in postharvest fragrant pears treated by ozone during the middle and late stages of shelf life. The activity and expression of antioxidant-related enzymes in postharvest fragrant pears were stimulated by ozone to accelerate the metabolism of ROS and maintain high quality, especially in the middle and late shelf lives.

Water loss is a key factor affecting the postharvest quality and shelf life of blueberries, and storage conditions (humidity and time) play an important role in regulating water retention capacity of stored berries. This study aims to explore the variation of moisture content (MC) in blueberries under different storage humidity and storage time conditions and to construct a prediction model for MC based on hyperspectral imaging. Four storage times (0, 7, 14, and 21 days) and three relative humidity (RH) levels (96%, 75%, and 56%) were set up in the experiment, and a hyperspectral imaging (HSI) system was used to collect image data of blueberries stored under different treatment conditions at 1.5°C. After preprocessing the spectral data using techniques such as denoising, normalization, and absorbance conversion, the partial least squares regression (PLSR) method was used to establish a water content prediction model. The results show that the model developed using data from a specific storage time has higher prediction accuracy than that from across the various storage periods. X‐loadings analysis shows that the 652–699 nm and 961–984 nm bands in the Vis‐NIR range have significant contributions to the MC estimation model. The best‐performing model was obtained for berries stored for 21 days at varying RH conditions (R ² = 0.74; root mean square error (RMSE) = 1.0% MC). Additionally, using the same spectral input data, compression firmness of the berries after 21 days of coolstorage could be estimated using PLS models with reasonable accuracy (R ² = 0.67; RMSE = 0.47 N).