Damage–Safety Trade-Offs in the Transition of Apple Harvesting Methods: Impacts of Mechanized and Intelligent Harvesting on Fresh-Market Quality and Food Safety

Apple harvesting is transitioning from conventional manual picking to harvest-assist platforms, vibration-based mechanical systems, and selective robotic harvesting. For fresh-market apples, harvesting efficiency cannot be evaluated independently of mechanical damage, postharvest quality deterioration, and food-safety risks. Compression bruising, impact bruising, abrasion, cuts, punctures, and stem-end tearing can disrupt the peel, cuticle, and cellular structure to different degrees, triggering reactive oxygen species accumulation, membrane lipid peroxidation, cell-wall degradation, enzymatic browning, and increased respiration and ethylene metabolism. These responses may subsequently be amplified during storage, transportation, and processing, leading to softening, decay, shortened shelf life, and potential patulin contamination. Centered on the damage–safety trade-off, this review compares the technical characteristics and typical damage profiles of manual harvesting, vibration-based mechanical harvesting, harvest-assist platforms, and selective harvesting robots; explains how mechanical damage is transmitted from cellular physiological responses to food-quality and safety outcomes; and proposes conceptual frameworks for a Damage Risk Index and a Harvest Suitability Score. The central objective of intelligent apple harvesting should therefore be to improve efficiency while preserving appearance, texture, nutritional quality, storage stability, and food safety.