Thermoforming is one of the most widely used manufacturing processes in food packaging production. It works by heating a plastic sheet until it becomes pliable, then forming it over or into a mould to create a specific shape. The process is fast, cost-effective, and capable of producing high volumes of consistent, food-safe packaging. The sections below answer the most common questions about how thermoforming works in food packaging, what materials it uses, and how to get the most from it.
What types of food packaging are made using thermoforming?
Thermoforming is used to produce a wide range of food packaging formats, including cups, lids, trays, bowls, clamshell containers, and coffee capsules. The process is particularly well suited to packaging that requires a precise, repeatable shape and a food-safe surface finish, making it the dominant production method across dairy, beverage, and ready-meal categories.
In the dairy sector, yogurt cups and margarine tubs are among the most common thermoformed products. These require tight dimensional tolerances so that lids seal correctly and stacking remains stable throughout logistics. Beverage lids, including those used for hot and cold drinks in foodservice, are also produced at high volume using thermoforming because the process delivers the consistency needed for reliable sealing.
Beyond cups and lids, thermoforming is widely used for fresh produce trays, ready-meal containers, and blister packs for portioned food items. Coffee capsules represent a more precision-demanding application, where the geometry of the capsule must be exact to ensure correct extraction pressure and airtight sealing. Food packaging accounts for roughly half of all thermoformed plastic packaging production, reflecting how well the process suits the specific demands of the food and beverage industry.
How does the thermoforming process work step by step?
The thermoforming process begins with a flat plastic sheet or roll that is fed into a machine, heated to a specific temperature until it becomes soft and malleable, then formed into shape using a mould, cooled to hold that shape, and finally trimmed to produce finished parts. The entire cycle repeats continuously in production, enabling high output rates.
Here is a more detailed breakdown of each stage:
- Sheet feeding: A roll or stack of plastic sheet is fed into the thermoforming machine at a controlled rate.
- Heating: The sheet passes through a heating zone where it is brought to the correct forming temperature. The temperature varies depending on the material and part geometry.
- Forming: The heated sheet is pressed or drawn into a mould using a combination of mechanical force, vacuum, and sometimes compressed air. This gives the packaging its final shape.
- Cooling: The formed part is cooled rapidly so it retains its shape when removed from the mould.
- Trimming and stacking: Finished parts are trimmed from the sheet, stacked, and prepared for downstream processes such as filling, sealing, or labelling.
In inline production setups, the plastic sheet is extruded and fed directly into the thermoforming machine without cooling and reheating, which saves energy and maintains material quality. The thermoforming process is highly adaptable, with mould changes allowing manufacturers to switch between product formats relatively quickly.
What plastic materials are used in thermoformed food packaging?
The most commonly used plastic materials in thermoformed food packaging are polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), and polylactic acid (PLA). Each material offers a different balance of rigidity, clarity, barrier performance, and compatibility with food contact regulations.
Polypropylene is widely used for yogurt cups, margarine tubs, and hot-fill containers because it withstands higher temperatures and offers good chemical resistance. Polystyrene is lightweight and easy to form, making it a common choice for lids and trays, although its use is declining in some markets due to recycling challenges. PET is valued for its clarity and recyclability, particularly in applications where product visibility is important, such as fresh produce packaging and beverage cups.
Sustainability considerations are reshaping material choices in thermoforming food packaging. Recycled PET (rPET) is increasingly used as brands and manufacturers work to increase recycled content in their packaging. Bio-based materials such as PLA, which is derived from plant starch, are also entering production lines, particularly where compostability is a priority. Processing these newer materials requires thermoforming machines capable of handling a broader range of forming temperatures and material behaviours.
What’s the difference between inline and standalone thermoforming machines?
Inline thermoforming machines are directly connected to an extruder, forming packaging from freshly produced plastic sheet without an intermediate cooling and reheating step. Standalone machines process pre-made plastic rolls or sheets independently of extrusion. The key difference is efficiency: inline systems reduce energy use and material degradation, while standalone machines offer greater flexibility for smaller runs or multiple material types.
In an inline configuration, the extrusion and thermoforming steps are synchronised into a single continuous process. Because the plastic sheet is never fully cooled between extrusion and forming, the system avoids the energy cost of reheating. This makes inline setups particularly attractive for high-volume, single-material production lines where consistent output is the priority.
Standalone thermoforming machines offer a different kind of value. They can process a wider variety of pre-made sheet materials and are easier to reconfigure for different products or materials. For manufacturers producing multiple packaging formats or working with specialty films, a standalone machine provides the operational flexibility that a fixed inline line cannot. Many production facilities use a combination of both, matching the configuration to the specific output requirements of each product line. Explore the full range of thermoforming machine options to understand which configuration suits your production needs.
How does thermoforming compare to injection moulding for food packaging?
Thermoforming and injection moulding are both used to produce plastic food packaging, but they differ significantly in cost structure, output speed, and design flexibility. Thermoforming is generally faster and more cost-effective for thin-walled, high-volume packaging such as cups and lids, while injection moulding is better suited to thick-walled, structurally complex parts where dimensional precision is critical.
The tooling cost for thermoforming moulds is typically lower than for injection moulding tools, which makes thermoforming more accessible for manufacturers who need to change formats regularly or who are producing a wide variety of packaging sizes. Thermoforming also produces less material waste per cycle for thin-walled parts, and the process runs at higher cycle speeds for these applications.
Injection moulding produces parts with more uniform wall thickness and can achieve tighter tolerances on complex three-dimensional geometries. For applications such as reusable food containers, closures with integrated threads, or parts requiring structural integrity under load, injection moulding may be the preferred choice. However, for the core categories of food packaging production, including dairy cups, beverage lids, trays, and capsules, thermoforming delivers the combination of speed, cost efficiency, and output volume that makes it the industry standard.
What factors affect output and efficiency in thermoforming production?
Output and efficiency in thermoforming food packaging production are primarily determined by cycle speed, mould configuration, material consistency, machine stability, and the degree of automation in downstream handling. Optimising these factors together is what separates high-performing production lines from average ones.
Cycle speed depends on how quickly the machine can complete each forming, cooling, and trimming cycle. Machines with advanced drive technology and optimised motion sequences can achieve higher cycle rates without compromising part quality. Mould configuration also plays a significant role: a larger mould with more cavities produces more parts per cycle, but only if the machine can maintain consistent forming pressure and temperature across the entire mould surface.
Material consistency affects both cycle time and part quality. Variations in sheet thickness or temperature distribution across the sheet lead to forming defects and increased scrap rates. Machines that maintain precise temperature control across the heating zone reduce these variations significantly.
Automation in stacking, counting, and downstream handling reduces labour costs and the risk of damage to finished parts. Integration with Industry 4.0 systems, including sensor monitoring and remote access, allows production managers to track machine performance in real time, identify inefficiencies early, and reduce unplanned downtime. Together, these factors determine the true cost per unit produced and the speed at which a capital investment pays back.
How GABLER Thermoform supports your food packaging production
We design and build high-end thermoforming machines specifically for food packaging production, combining advanced drive technology, precision engineering, and full-service support into a single solution. Our machines are built to deliver measurable performance advantages across the factors that matter most in production:
- Higher output: Our high-end machines achieve up to 20 per cent higher output than comparable systems, reducing cost per unit and accelerating return on investment.
- Optimised motion sequences: A fixed top yoke, tilting bottom table, and separate servo drives for lifting and swivelling minimise tool wear and support higher cycle rates.
- Material flexibility: Our machines are capable of processing conventional plastics as well as recycled PET and biodegradable PLA foil, supporting your sustainability goals.
- Industry 4.0 readiness: State-of-the-art sensor technology and remote access give you full visibility of machine performance and enable proactive maintenance.
- Full-service support: From installation and commissioning through to spare parts supply and ongoing customer service, we provide a complete carefree package.
Whether you are scaling up dairy cup production, introducing new packaging formats, or transitioning to more sustainable materials, we are ready to support you with the right machine and the right expertise. Contact GABLER Thermoform to discuss your production requirements and find the solution that fits your operation.