Cold storage can protect fruit from decay, but for some species it produces a dry, grainy or mealy texture. The core cause is chilling injury, a set of physiological disruptions when susceptible fruits experience low but nonfreezing temperatures. Research by David Crisosto at the University of California Davis links mealiness in stone fruits to altered cell wall metabolism during cold storage, where normal ripening enzymes are suppressed or misregulated and pectin modifications prevent cells from rehydrating properly.
Causes at the cellular level
At a microscopic level, mealiness reflects changes in cell wall pectin and cell membrane integrity. Enzymes that normally soften fruit by breaking down pectin are inhibited or show altered activity after chilling. This leads to the formation of water-insoluble pectin and loss of cell-to-cell adhesion. Simultaneously, membranes become less permeable and leak cellular fluids unevenly, so juice that would normally make flesh feel juicy is trapped inside cells or lost. Ethylene-dependent ripening pathways may also be disrupted, so surface softness can occur without the internal juiciness consumers expect. Varietal sensitivity, harvest maturity and the exact storage temperature and duration all influence whether chilling injury appears.
Broader relevance and consequences
Mealiness reduces consumer acceptance and increases food waste across supply chains. For producers and distributors, the consequence is economic loss through downgraded fruit and shorter market windows. For smallholder farmers and regions with limited cold-chain control, improper or inconsistent refrigeration can inadvertently induce mealiness, shifting practices such as selling fruit at slightly warmer temperatures or altering harvest timing. Environmentally, extended cold storage and corrective measures such as controlled-atmosphere systems raise energy use, creating a trade-off between spoilage prevention and carbon footprint.
Postharvest management strategies focus on preventing chilling by using optimal storage temperatures for each species, applying preconditioning treatments to allow ripening enzymes to activate before cooling, and employing controlled-atmosphere storage to slow senescence without triggering chilling responses. Consumer education also matters because home refrigeration of sensitive fruits like peaches and nectarines at very low refrigerator temperatures can provoke mealiness. Understanding which cultivars are tolerant and following guidelines developed by postharvest researchers helps maintain texture while minimizing spoilage, balancing quality, cultural supply-chain realities and environmental costs.