From skin barrier to shelf stability: Pretreatment, drying, and packaging strategies for blueberry quality preservation

This is the authors' abstract. We don't add key points for this paper.

The wax-rich cuticular layer of blueberries, together with their high perishability and delicate internal structure, creates major challenges for dehydration, freezing, drying, and long-term preservation. This review synthesizes recent advances in blueberry preservation from a skin-barrier-to-shelf-stability perspective, with emphasis on how surface resistance controls moisture transport, product quality, and storage performance. Pretreatments are organized according to their dominant effects: physical disruption of the cuticle and epidermal tissues, membrane permeabilization by electric fields, volumetric or infrared-assisted heating, cryogenic or freezing-induced structural modification, and chemical or enzymatic alteration of waxes and cell-wall components. Across the reviewed studies, these approaches can enhance water removal and solute exchange, accelerate drying, increase apparent effective moisture diffusivity, and influence rehydration behavior. However, transport improvement does not always ensure better product quality. Excessive permeability, high temperature, uneven energy delivery, or severe tissue disruption may increase pigment degradation, enzymatic browning, juice loss, texture collapse, or reduced visual and sensory quality. Therefore, each strategy is evaluated in relation to both processing efficiency and quality attributes, including color, texture, microstructure, water activity, phenolics, anthocyanins, antioxidant capacity, and rehydration behavior. The review also highlights the need to connect pretreatment and drying outcomes with validated storage and packaging performance. For dried blueberries, shelf stability should be linked to water activity, sorption behavior, glass-transition-related physical stability, and moisture- and oxygen-barrier packaging. Future research should prioritize standardized reporting, cultivar- and maturity-specific validation, sensory evaluation, shelf-stability endpoints, sustainability indicators, and techno-economic analysis.