In the berry sector, even minor technical failures can lead to significant losses. Strawberries, raspberries and blueberries are highly delicate: they bruise easily, respire rapidly and deteriorate quickly if conditions are not optimal. In this context, the most effective improvements often come not from dramatic innovations, but from consistent control of the fundamentals. Tray sealing is one of those fundamentals.
Why tray sealing has become the industry standard
Across packing operations, reliability remains the top priority. Heat sealing provides a stable, repeatable packaging solution, unlike clip-on lids that can shift due to handling or machine settings.
For berries, a single defective seal does not just mean the loss of one pack — it can disrupt automated retail and distribution systems further down the supply chain. Consistency in sealing therefore becomes essential for maintaining operational flow and product integrity.
Material flexibility supports sustainability goals
As sustainability requirements evolve, packhouses are working with a wider range of materials: APET, fiber trays, mono-material films and paper-based solutions. Tray sealing allows these transitions to take place without fundamentally redesigning the packaging line. This flexibility has become a cornerstone of sustainability strategies in the berry category.
Matching atmosphere control to the fruit
Modified atmosphere packaging (MAP) is not a one-size-fits-all solution for berries, which are too sensitive for aggressive vacuum levels. More refined approaches are increasingly used:
- MAP-F systems for subtle oxygen and CO₂ adjustments,
- MAP-V with very moderate gas levels,
- or natural atmospheric systems that rely on carefully selected film permeability and tray ventilation to match the fruit’s respiration rate.
These solutions are often simpler, less energy-intensive and aligned with the industry’s drive to achieve more with less intervention.
A practical example: transitioning to paper-based film
A recent example highlights this evolution. Emery Soft Fruits in the UK needed to integrate paper-based film on PET trays for Ocado. Although seemingly straightforward, paper films present technical challenges due to moisture absorption and print variability.
By installing a contrast sensor and adapting machine programming, the engineering team enabled operators to switch easily between different film types using pre-set “recipes.” The solution ensured consistent performance regardless of the operator and has since become a model for similar transitions.
The importance of real-world testing
Experience shows that even the best technical advice cannot replace real machine trials using the customer’s trays and films. Testing centers therefore play a critical role in validating new materials and MAP configurations under realistic conditions.
For berries, where fruit quality can vary daily, controlled testing environments allow packers to fine-tune sealing parameters before full-scale production, reducing risk and minimizing waste.
Managing peak-season pressure
Anyone involved in berry production understands how quickly volumes can surge during peak season. Operations may move from steady throughput to maximum capacity almost overnight. Equipment must absorb these spikes without damaging fruit or compromising seal integrity.
Precise control of denesting, feed flow and sealing pressure becomes essential. A stable sealing process reduces downtime and unexpected stoppages — two factors that directly influence profitability in short-season crops.
A foundation for the future of berry packaging
With decades of industry experience, one conclusion stands out: the berry sector rewards consistency over complexity. While the future will bring more recyclable materials, greater automation and fewer line operators, the fundamentals will remain unchanged — protect the fruit, manage its atmosphere and stabilize the process.
Tray sealing continues to be one of the most controlled and adaptable solutions to meet these objectives, supporting producers and packers as they navigate evolving material, sustainability and performance requirements.