Essential Functions and Properties of Packaging Materials for Fresh Produce

Every year, approximately 1.3 billion tonnes of fresh fruits and vegetables are lost globally – much of it before the food even reaches a consumer’s plate. A significant share of this loss comes down to one overlooked factor: the packaging. Packaging for fresh produce is far more than a wrapper or a container. It is a carefully engineered system that contains, protects, preserves, and communicates – all at once. Understanding what packaging materials are expected to do, and what properties they must carry to do it well, is central to reducing post-harvest losses and delivering quality produce from farm to consumer.

The core functions of packaging materials 🔗

A properly designed produce container must contain, protect, and identify the produce – satisfying everyone from grower to consumer. These are not separate goals; they work together as a system. Let’s look at each function in detail.

Containment 🔗

The most basic function of any packaging material is to hold the produce together in a convenient, manageable unit. Bags, crates, hampers, cartons, bulk bins, and palletized containers are all designed to make handling, transporting, and marketing fresh produce more efficient. Good containment means the produce fits the package with minimum wasted space – reducing movement inside the container that leads to bruising, and optimizing the use of transport and storage space.

Containment also determines pack size. Consumer-oriented packages are typically limited to around 50 lb for easy manual handling, while bulk bins moved by forklifts can hold considerably more. Choosing the wrong unit size leads to inefficiencies across the entire supply chain.

Protection from mechanical damage 🔗

Fresh fruits and vegetables are biologically active and physically fragile. Without adequate protection, even short transit distances result in bruising, cuts, and compression injuries that make produce unsellable. The package must protect the produce from mechanical damage and hostile environmental conditions during handling and distribution. The condition of the package, in fact, often reflects the condition of its contents – damaged or collapsed containers are a reliable sign of mishandled produce.

For delicate items like strawberries or mangoes, individual or separated packing using molded trays or cushioning pads is recommended. Individual packing ensures each item’s microenvironment and reduces physical contact between units, limiting both bruising and the spread of disease-causing pathogens.

Protection from environmental hazards 🔗

Temperature fluctuations, excessive moisture loss, and contamination from dust, microorganisms, and physical pollutants are constant threats during the postharvest journey. Packaging containers should maintain an optimum environment for the longest shelf life, which may involve special materials to slow water loss from the produce, insulation to repel heat, or engineered plastic liners that maintain a favorable mix of atmospheric gases.

From a microbial standpoint, the FDA’s produce safety regulations require that food-packing material must be adequate for its intended use, cleanable or designed for single use, and unlikely to support the growth or transfer of bacteria. Non-toxic, food-safe materials are a non-negotiable baseline.

Preservation of quality and extension of shelf life 🔗

Fresh produce continues to respire after harvest. This ongoing biological activity consumes oxygen, releases carbon dioxide and ethylene, generates heat, and leads to moisture loss – all of which accelerate ripening, senescence, and decay. Packaging plays a direct role in managing these processes.

Modified atmosphere packaging (MAP) manages the in-package gas environment, and the in-package humidity level must also be considered to avoid condensation and mould or bacterial development. By creating a reduced-oxygen, elevated-carbon-dioxide atmosphere inside the package, MAP slows respiration, delays softening, and extends shelf life significantly.

Ethylene management is equally important. Ethylene causes shorter storage life, promotes senescence, softening, discoloration, and increases susceptibility to decay in fresh produce. Packaging materials that can absorb or block ethylene therefore play a meaningful role in maintaining quality during storage and transit.

Providing product information 🔗

Packaging is also a communication tool. The package must identify and provide useful information about the produce – typically including the produce name, brand, size, grade, variety, net weight, count, grower, shipper, and country of origin. This information is not just commercial convenience; it supports traceability, regulatory compliance, and consumer trust.

Under international frameworks such as the Codex Alimentarius General Standard for Labelling of Prepackaged Foods, pre-packaged produce labels should carry the food name, lot identification, date marking, and any special storage conditions. Clear labeling also enables buyers to assess freshness and handle the product correctly – reducing losses caused by improper storage downstream.

Essential properties of packaging materials 🔗

For packaging to carry out all the functions described above, the materials themselves must possess a set of well-defined physical, chemical, and mechanical properties. Selecting the wrong material – even with good design – can result in packaging failure and produce losses.

Mechanical properties 🔗

Packaging materials must physically survive the supply chain. Tensile strength determines how much force a material can withstand before tearing; flexibility allows materials to bend without breaking; and impact resistance determines how well packaging withstands sudden forces or drops. Corrugated fiberboard cartons, for instance, rely on their fluted inner layer for compression resistance, while polyethylene bags rely on tensile strength and flexibility to avoid tearing during mechanical filling and transport.

For fresh produce specifically, packaging materials also need adequate stacking strength. A carton that cannot bear the weight of stacked boxes above it will collapse, causing both packaging failure and produce damage – one of the most common complaints traced back to poor material selection.

Barrier properties 🔗

Barrier properties determine how well a packaging material controls the passage of gases, moisture, and light. Barrier properties include permeability to gases such as oxygen, carbon dioxide, and nitrogen, water vapour, aroma compounds, and light – all of which are vital factors for maintaining the quality of packaged foods.

For fresh produce, the balance between gas permeability and barrier performance is especially critical. A film that is too impermeable traps carbon dioxide and moisture, encouraging anaerobic conditions and mould. A film that is too permeable fails to create any modified atmosphere benefit. Most polymeric materials used in MAP – including polyethylene, polypropylene, and polyvinyl chloride – have lower water vapour permeability relative to the transpiration rate of fresh produce, so most water evaporated from the produce stays within the package, raising the internal humidity. Packaging engineers must account for this to prevent condensation problems.

When packaging is required at the source or when extended storage life is desired, the packaging film should have high gas permeability and anti-fog properties. Anti-fog coatings on the inner surface of films prevent water droplets from forming a visual haze, which would obscure the produce and reduce consumer appeal.

Physical and optical properties 🔗

Transparency is a practically important physical property for consumer-facing packaging. Transparency allows consumers to see the product inside, building trust and appeal – clear plastic containers for salads let customers inspect freshness before purchase. Plastic bags (polyethylene film) have long dominated fresh produce retail packaging partly because of this clarity, which allows easy visual inspection without opening the package.

Thickness also matters. Thicker materials generally offer better protection but use more resources and add cost and weight. Finding the right balance for each commodity is part of thoughtful packaging design.

Chemical compatibility and food safety 🔗

A packaging material must be chemically inert – it should not react with the produce, impart off-flavours or odours, or leach harmful substances into the food. This is a baseline safety requirement. Under the FDA’s produce safety rule, food-packing materials must be adequate for their intended use and unlikely to support the growth or transfer of bacteria. Materials that fail this requirement, regardless of their other properties, are unsuitable for fresh produce packaging.

Non-toxicity and food-contact compliance 🔗

Related to chemical compatibility is the requirement for non-toxicity. All food-contact packaging materials used for fresh produce must comply with food safety regulations in their respective markets. The FDA in the United States and corresponding bodies in other countries maintain lists of approved food-contact substances. This is not merely a regulatory formality – it directly protects public health.

Sustainability as an emerging property requirement 🔗

In recent years, environmental performance has become an increasingly important criterion alongside the traditional technical properties. Jurisdictions around the world are enacting legislation that limits or eliminates certain plastics, and reuse, recyclability, and even the total elimination of packaging are now top concerns in the produce industry.

This has accelerated the development of alternative materials. Edible coatings and wrappings made from natural biomaterials act as protective layers on fruits and vegetables, decreasing respiration, transpiration, ethylene production, and microbial deterioration, while extending postharvest shelf life. These materials – based on polysaccharides, proteins, and lipids – offer a path to reduced plastic use while maintaining functional packaging performance.

Corrugated fiberboard, despite being one of the oldest packaging materials in the supply chain, remains widely used precisely because it is recyclable, relatively lightweight, and printable. Traditional packaging materials including wood, corrugated fiberboard, bamboo, jute, polyethylene, and paper continue to serve practical roles, while modern innovations in nanotechnology, ultrasound processing, and intelligent packaging are being explored to improve produce quality and reduce food waste.

How these functions and properties work together 🔗

It is worth emphasizing that the functions and properties of packaging are not independent considerations – they interact. A material selected purely for its barrier properties may fail mechanically under stacking loads. A highly transparent film may transmit too much light, accelerating deterioration of light-sensitive produce. A fully biodegradable tray may lack the moisture resistance needed for high-humidity commodities.

Ideal packing material for fresh produce should combine appropriate gas permeability, mechanical strength, food-contact safety, and compatibility with the specific commodity’s respiration rate and physical characteristics. This is why packaging selection is not a one-size-fits-all decision – it requires matching the material’s properties to the biology and supply chain requirements of each crop.

The ultimate measure of success is simple: does the packaging deliver the produce to the consumer in a condition that reflects its quality at harvest? When functions are correctly fulfilled and properties are properly matched, packaging becomes a genuine tool for reducing post-harvest losses, protecting farmer income, and ensuring food security.

What do you think? Given that fresh produce continues to respire inside its package after harvest, how do you think packaging engineers should prioritize the balance between gas barrier properties and breathability – especially for high-respiration commodities like leafy greens or berries? And with sustainability concerns rising, do you think biodegradable or edible packaging can realistically replace conventional plastics across the entire fresh produce supply chain?

References

1. https://www.sciencedirect.com/science/article/abs/pii/S2214289424001509
2. https://content.ces.ncsu.edu/introduction-to-the-postharvest-engineering-for-fresh-fruits-and-vegetables/9-produce-packaging
3. https://www.intechopen.com/chapters/79725
4. https://marketready.uky.edu/sites/default/files/2022-06/Packaging%20Requirements%20for%20Fresh%20Fruits%20and%20Vegetables%20-%20NC%20State%20Extension.pdf
5. https://www.fda.gov/media/107298/download
6. https://pmc.ncbi.nlm.nih.gov/articles/PMC4006172/
7. https://www.fao.org/fao-who-codexalimentarius/sh-proxy/fr/?lnk=1&url=https://workspace.fao.org/sites/codex/Standards/CXS+1-1985/CXS_001e.pdf
8. https://fiveable.me/principles-food-science/unit-11/packaging-materials-properties/study-guide/r1VNvyOOGoB1MeHU
9. https://www.newfoodmagazine.com/article/16971/barrier-packaging-materials/
10. https://www.sciencedirect.com/science/article/pii/S2772753X24001072