Quality Control in Food Packaging: Testing and Standards

Every food product you pick off a shelf has survived a journey – from a processing plant, through warehouses, onto trucks, and finally into your hands. The packaging around it did the heavy lifting. But how do manufacturers know if their packaging is strong enough, moisture-resistant enough, or durable enough for that journey? The answer lies in quality testing of packaging materials – a systematic process that evaluates whether packaging can protect food products under real-world conditions of storage, handling, and transportation.

Why quality testing of food packaging matters 🔗

Food packaging does more than hold a product. It serves as a barrier against contamination, moisture, oxygen, light, and physical damage. If packaging fails at any of these roles, the consequences range from spoiled food and economic losses to serious consumer health risks. According to QIMA, food packaging testing ensures that materials are compatible with the food they contain and can withstand a wide range of conditions – from exposure to contaminants to rough handling during shipment.

Quality testing also plays a direct role in regulatory compliance. Organizations such as ASTM International, the International Organization for Standardization (ISO), and the U.S. Food and Drug Administration (FDA) have developed detailed protocols for evaluating packaging performance. These standards specify the testing methods, acceptance criteria, and reporting requirements that manufacturers must follow. Without rigorous testing, food companies risk product recalls, legal action, and loss of consumer trust.

Understanding tensile strength testing 🔗

Tensile strength measures how much pulling or stretching force a packaging material can withstand before it breaks. This is one of the most fundamental mechanical tests for packaging films and sheets. When a plastic film wraps around a block of cheese or a bag holds rice, the material must resist stretching forces without tearing.

The test works by clamping a strip of the packaging material between two grips and pulling it apart at a controlled speed until the material fails. The result is expressed as force per unit area, typically in megapascals (MPa). According to ZwickRoell, the standard ASTM D882 covers tensile testing for thin plastic films and determines key values including tensile strength, elongation at break, and yield point.

What tensile testing reveals 🔗

Tensile testing tells manufacturers several important things about a packaging film. First, it shows the maximum load the material can bear – critical for packaging that undergoes stretching during filling or sealing. Second, it reveals how much the material can elongate before failure, which is important for flexible packaging that needs to stretch around irregularly shaped products. Third, it identifies the yield point – the stress level at which the material begins to deform permanently. Materials with properties recorded under ISO 527-3 or ASTM D882 standards give engineers reliable data for selecting the right film for each application.

Bursting strength testing 🔗

Bursting strength measures the maximum pressure a packaging material can withstand before it ruptures when force is applied from multiple directions simultaneously. Unlike tensile testing, which pulls a material in one direction, burst testing applies biaxial stress – meaning force acts on the material from more than one direction at the same time.

This test is especially important for paper, paperboard, corrugated cardboard, and flexible pouches used in food packaging. As explained by Xometry, manufacturers use burst strength testing to confirm that their packaging can hold up during transportation, stacking, and rough handling – situations where pressure can come from unpredictable angles.

Key standards for burst testing 🔗

Several international standards govern burst testing. ASTM D3786 covers the bursting strength of textiles and nonwovens, while ISO 2759 applies to paperboard, including corrugated cardboard. For flexible food packaging seals, ASTM F2054 provides a method to evaluate the minimum burst strength of seals by internally pressurizing a package within restraining plates. This test is particularly valuable for pouches and sachets, where seal failure could lead to leakage and contamination.

Another commonly used approach is the Mullen test, which evaluates corrugated linerboard’s ability to resist external or internal forces. This test is widely applied for shipping boxes and cartons that must endure the pressures of warehouse stacking and transit handling.

Water vapor transmission rate (WVTR) 🔗

Moisture is one of the biggest enemies of food quality. Products like potato chips, biscuits, and powdered spices must stay dry, while cheese, bread, and fresh produce need to retain their natural moisture. The water vapor transmission rate (WVTR) measures how much moisture passes through a packaging material per unit area per unit time, typically expressed as grams per square metre per day (g/m²/day).

According to Measurlabs, WVTR is a key quality indicator for food and cosmetics packaging because an effective moisture barrier is critical for keeping products fresh and preventing spoilage. The standard test method ASTM F1249 measures WVTR by sealing a barrier film between a wet chamber and a dry chamber, then using a modulated infrared sensor to detect moisture transmitted through the material.

Why WVTR matters for food shelf life 🔗

A packaging material with a high WVTR allows too much moisture to pass through, which can make crispy foods soggy or cause dry products to clump. Conversely, a packaging film with very low WVTR helps extend the shelf life of moisture-sensitive products. The WVTR of a material depends on several factors including its thickness (thicker films provide better barrier), polymer crystallinity (higher crystallinity means lower WVTR), and temperature and humidity conditions during storage.

For comprehensive barrier evaluation, manufacturers also measure the oxygen transmission rate (OTR), which determines how much oxygen permeates through the material. Together, WVTR and OTR data guide manufacturers in selecting or designing multi-layer packaging structures that offer the right balance of moisture and gas barrier properties for each food product.

Impact resistance testing 🔗

Food packages endure drops, bumps, and collisions throughout the supply chain. Impact resistance testing evaluates how well a packaging material or a completed package withstands sudden shocks or forces. This is essential for products packaged in glass bottles, rigid plastic containers, or corrugated cartons.

There are two primary approaches to impact testing. The drop test simulates real-world drops by releasing a package from a specified height onto a hard surface, testing flat faces, edges, and corners. Standards such as ASTM D5276 and the ISTA 1A protocol define the procedures for conducting drop tests based on product weight and shipping conditions. The second approach is the dart impact test (ASTM D1709), where a weighted dart is dropped onto a flat film specimen to determine the energy required to cause failure.

Puncture resistance 🔗

Closely related to impact resistance, puncture testing measures a material’s ability to resist penetration by sharp objects. This is particularly relevant for flexible films that might encounter sharp edges during stacking or handling. ASTM F1306 tests slow-rate penetration resistance of flexible barrier films, while ASTM D5748 evaluates puncture through a protrusion test. Packaging that fails puncture testing is at high risk of developing micro-holes that can allow bacteria, moisture, or oxygen to reach the food inside.

Seal integrity and peel strength testing 🔗

Many food packages rely on heat seals to keep the product enclosed. A weak seal can lead to leaks, contamination, and reduced shelf life. Seal integrity testing checks whether the seals on a package are complete and free of defects, while peel strength testing measures the force required to separate a sealed joint.

According to ZwickRoell, peel tests on packaging seals are typically performed on 15-mm wide strips at a 180-degree peel angle under standards such as DIN 55529. The seal must demonstrate a certain stiffness depending on the type of packaging material used. Meanwhile, leak detection tests – such as ASTM D3078 (bubble emission method) or vacuum decay methods – verify that no micro-leaks exist in the finished package.

Why seal testing is non-negotiable 🔗

A package may have excellent barrier properties in its film material, but if the seal is compromised, all of that protection is lost. Seal failures are one of the most common causes of food spoilage in flexible packaging. This is why seal strength testing is performed not just during product development, but regularly during manufacturing as part of in-process quality control.

Compression testing 🔗

When packages are stacked on pallets in warehouses or inside shipping containers, the ones at the bottom bear the weight of everything above. Compression testing determines how much stacking load a package can sustain before it deforms or collapses.

The test involves placing the package between two flat plates and applying a progressively increasing load until the package fails. ASTM D642 is the standard method for determining the compressive resistance of shipping containers. For corrugated boxes, the Edge Crush Test (ECT) measures the force required to crush the corrugated board standing on its edges, which directly relates to stacking strength.

Compression testing data is critical for supply chain planning. It determines how high packages can be safely stacked during storage and transport, preventing product damage and reducing waste.

Additional quality tests for food packaging 🔗

Tear resistance 🔗

Tear resistance testing measures the force needed to propagate a tear in a packaging material after an initial cut has been made. The Elmendorf tear test (ISO 6383) is commonly used for plastic films. This is important because during package opening or rough handling, a small tear should not propagate uncontrollably across the entire film – especially when the package contains food that could spill.

Coefficient of friction (COF) 🔗

The coefficient of friction measures how easily one packaging surface slides against another. This may sound minor, but it affects how films move through packaging machinery, how bags stack on shelves, and how packages slide during palletization. If a film is too slippery, packages may slide off a pallet; if too sticky, they may jam the filling machine.

Migration testing 🔗

Beyond physical tests, chemical migration testing is essential for food packaging safety. This evaluates whether chemical substances from the packaging material transfer into the food. Both overall migration (total substances transferred) and specific migration (individual substances like phthalates, BPA, or heavy metals) are measured. Regulatory agencies including the FDA and EFSA set strict limits on permissible migration levels.

Environmental conditioning tests 🔗

These tests expose packaging to controlled temperature and humidity extremes to simulate real-world conditions during storage and transport. For example, a package shipped from a cold warehouse to a hot delivery truck must maintain its structural and barrier integrity despite rapid temperature changes. Altitude simulation testing is also used for products transported by air, where reduced pressure can stress sealed packages.

The role of standards in packaging quality 🔗

Quality testing without standardized procedures would produce inconsistent and unreliable results. That is why globally recognized organizations provide the framework that packaging testing follows:

ASTM International has developed hundreds of packaging-related standards covering everything from tensile strength (ASTM D882) and burst strength (ASTM D3786) to seal integrity (ASTM F88) and water vapor transmission (ASTM F1249). These standards provide detailed procedures, specimen requirements, and reporting formats.

ISO standards offer internationally harmonized testing methods. ISO 2758 covers paper bursting strength, ISO 527-3 addresses plastic film tensile properties, and ISO 11607 sets requirements for medical device packaging – principles that also influence food packaging practices.

ISTA (International Safe Transit Association) focuses on transport simulation testing. Their test protocols replicate the hazards packages encounter during distribution, from vibration and compression to drops and atmospheric conditioning.

Compliance with these standards not only ensures product safety but also builds credibility with retailers, regulators, and consumers across markets.

Building a packaging quality control programme 🔗

Effective quality control in food packaging is not a one-time activity – it is an ongoing programme integrated into every stage of packaging development and production. Here is a practical approach:

Material qualification: Test all incoming raw materials (films, foils, adhesives, inks) against specifications before they enter the production line. Tensile strength, WVTR, and migration testing are typical at this stage.

In-process testing: Monitor seal strength, fill weight accuracy, and visual defects during the packaging operation. This catches problems early before large batches are affected.

Finished package testing: Subject completed packages to drop tests, compression tests, and leak detection to confirm they meet performance requirements.

Shelf life validation: Use accelerated ageing tests under elevated temperature and humidity to predict how packaging performance will change over the product’s intended shelf life.

Continuous improvement: Track test results over time to identify trends, optimise material usage, and reduce costs without compromising protection.

What do you think? Given the growing demand for sustainable and recyclable food packaging materials, how do you think quality testing protocols will need to evolve to keep pace? And does the packaging of a food product influence your own purchasing decisions more than you realise?

References

1. https://blog.qima.com/food-contact/food-packaging-testing-methods
2. https://store.astm.org/products-services/standards-and-publications/standards/paper-standards-and-packaging-standards.html
3. https://www.zwickroell.com/industries/plastics/thin-sheeting-and-plastic-films/astm-d882-film-tensile-test/
4. https://www.xometry.com/resources/materials/burst-strength/
5. https://industrialphysics.com/standards/f-2054/
6. https://measurlabs.com/methods/water-vapor-transmission-rate-wvtr/
7. https://peekage.com/blog/packaging-testing-methods
8. https://www.zwickroell.com/industries/food-packaging/testing-of-packaging/
9. https://en.wikipedia.org/wiki/Package_testing