From Field to Supermarket: Protecting Fresh Produce

The Cold Chain Challenge

Paper is inherently hygroscopic; its cellulose fibers naturally seek to absorb water from the environment. In a refrigerated sea container (reefer) operating at 2-4°C and 90-95% Relative Humidity (RH), uncoated paper acts as a sponge.

• Fiber Swelling: As moisture enters, the hydrogen bonds between paper fibers weaken.
• Loss of Rigidity: The board loses its stiffness (ECT) and stacking strength (BCT).
• The Domino Effect: Bottom boxes in a pallet crush under the weight, bruising the fruit, restricting cold air circulation, and accelerating spoilage.

The Failure Modes of Generic Packaging

Before implementing our solutions, many agricultural exporters settle for standard packaging with minimal sizing. This leads to distinct and costly failure modes:

• Condensation Collapse: Moving pallets from cold storage to warmer packing areas causes immediate condensation (sweating), destroying box integrity in minutes.
• Friction Scuffing: Vibrations during ocean transit cause softened, wet boxes to rub against each other, erasing branding and exposing raw fibers.
• Bottom Sag: Moisture accumulating at the bottom of the pallet causes the flaps to yield, dropping the fruit.

The Anatomy of a Solution: Coaterex Functional Coatings

We partnered with several major Latin American fruit exporters who were facing combined rejection and repackaging rates of up to 5-8% at destination ports. We engineered a specific barrier strategy utilizing our VaporCoat® and HydraBan® lines.

• Targeted Moisture Repellency: Coatings applied to the inner and outer liners prevent exactly both vapor penetration and liquid condensation.
• Maintained BCT: By sealing the fibers, the board retains up to 80% of its dry compression strength even in 90% RH environments.
• Sustained Glueability: Formulated to ensure that the erected trays maintain their glued joints even under extreme cold.

Specific Solutions by Fruit Type

Not all produce breathes or sweats the same way. Our approach is tailored to the crop:

• Bananas & Plantains: Require high moisture hold-out inside the box to deal with the fruit's own transpiration during the ripening cycle.
• Stone Fruit & Berries: Often hydro-cooled or packed with ice pads. Require extreme liquid water resistance (Cobb <20) to prevent the bottom from falling out.
• Citrus: Often travel in open-top trays that require high scuff resistance and excellent print protection against condensation.

The Sustainability Mandate

Historically, the industry solved this with wax. Today, supermarket chains in Europe and the US refuse waxed boxes because they cannot be recycled and end up in landfills. Our functional coatings offer a 1-to-1 replacement for wax with a crucial difference:

• 100% Repulpable: Certified to break down completely in standard recycling hydrapulpers.
• Closing the Loop: Retailers can now sell the used boxes to recyclers instead of paying for landfill disposal, improving their own ESG metrics.

Measurable Results & ROI

After transitioning to the Coaterex barrier system, the metrics across multiple harvest seasons demonstrated clear financial and operational success:

• 0% Box Failure: Complete elimination of crushed boxes attributed to moisture weakening in over 500 trial shipments.
• Brand Protection: Graphics and branding remained pristine upon arrival, improving retail presentation.
• Cost Neutrality: The marginal cost of the premium coating was entirely offset by the savings from zero product loss and eliminated repacking labor at destination.

The Path Forward for Exporters

Protecting produce is no longer just about getting it there; it's about getting it there sustainably and profitably. By upgrading the functional barrier of the box, exporters protect their most valuable asset—their product—while aligning with the strict environmental demands of modern global retail.