Postharvest quality

Cucumber postharvest quality is primarily determined by water status, texture and skin colour.

Cucumbers are highly sensitive to weight loss, and even small levels of dehydration can lead to a loss of firmness and turgidity. Once weight loss exceeds approximately 2%, cucumbers often become visibly less turgid and are generally no longer acceptable to consumers.

Cucumbers do not produce ethylene, but they are highly sensitive to ethylene produced by other crops. Exposure to ethylene accelerates softening and yellowing of the skin due to chlorophyll degradation. Higher ethylene concentrations shorten the allowable storage and marketing period.

If cucumbers are harvested or held beyond the optimal commercial stage, they may develop a bitter taste, reducing eating quality. In addition, cucumbers are sensitive to chilling injury, particularly when stored below approximately 7 °C, depending on cultivar and storage duration. Typical chilling injury symptoms include water-soaked areas, pitting of the skin, and accelerated quality decay during subsequent handling and retail.

Packaging and postharvest treatments

Packaging plays a central role in maintaining cucumber quality by limiting moisture loss.

• Shrink-film packaging (LDPE) is widely used. Cucumbers are packed in LDPE film and briefly heated to shrink the film tightly around the fruit, effectively reducing transpiration. Under these conditions, cucumbers can be displayed in supermarkets at room temperature and relatively low ambient humidity with limited quality loss.
• When plastic film is not used, cucumbers are often packed in cardboard boxes, which help maintain a high relative humidity in the immediate surroundings of the fruit and thereby reduce weight loss.
• In open packaging systems (e.g. plastic crates without lids), cucumbers should be stored at high ambient relative humidity to slow dehydration.
• Edible coatings or waxes may be applied to further reduce moisture loss. Such coatings should not negatively affect appearance, taste or consumer acceptance.
• Laser printing can be used for product identification or branding, provided it does not cause skin or flesh damage.