Comprehensive guide to understanding industrial cooking tunnels, comparing available technologies and selecting the solution best suited to your production line.
What is a food production cooking tunnel?
A food production cooking tunnel is a continuous cooking system designed for industrial production lines. Unlike discontinuous (or batch) ovens that process products in lots, the cooking tunnel moves products on a conveyor through different controlled temperature zones, allowing for homogeneous and consistent cooking.
This type of equipment takes the form of a tunnel equipped with a conveyor belt made of stainless steel or metal mesh. The products successively pass through several heating zones where they undergo different thermal treatments according to the recipe: progressive temperature rise, core cooking, drying, and then cooling.
The main difference with traditional industrial food ovens lies in the continuous operating mode, which guarantees high throughput and constant quality, particularly suited to the large volumes of modern industrial production.
Main applications in the food industry
Industrial cooking tunnels are used in many sectors of the food industry. Common applications include the baking of bakery and biscuit products (bread, pastries, biscuits, crackers), the production of ready meals in trays, the processing of meat and fish, the cooking of vegetables for canning or freezing, the manufacture of dairy desserts, as well as the production of snacks and aperitif products.
Each application requires specific parameters for temperature, conveying speed, and cooking mode, which explains the diversity of technologies available on the market.
Main cooking tunnel technologies
Forced air cooking tunnel: This technology uses forced hot air circulation to ensure homogeneous cooking. Ventilation allows for uniform heat distribution around the products, ideal for ready meals, meat, vegetables, and desserts. Temperatures and airflows are adjustable zone by zone to adapt to the different cooking phases.
Steam / pasteurisation cooking tunnel: Operating with saturated or superheated steam, this type of tunnel allows for gentle cooking at temperatures generally between 95°C and 120°C. It simultaneously ensures the cooking and pasteurisation of products, particularly suited to products in sealed trays, sauces, and sensitive preparations where maintaining texture is paramount.
Hot air / infrared tunnel oven: This equipment combines radiant heat and convection for fast cooking and controlled browning. Particularly effective for biscuits, crackers, pizzas, snacks, and bakery products, they offer high production throughputs with constant and reproducible quality.
Combined or mixed tunnels: These scalable solutions integrate several cooking modes into a single piece of equipment. For example, an initial steam zone for gentle core cooking, followed by a forced air zone for browning and drying. This modularity allows different types of products to be processed on the same line with maximum flexibility.
How does an industrial cooking tunnel work?
The operating principle of a continuous tunnel oven is based on the controlled movement of products through different thermal zones. The conveying system is the central element of this process.
Conveyor principle
The conveyor generally consists of a stainless steel belt or metal mesh, depending on the type of products processed. The belt speed is fully adjustable and determines the residence time of the products in each cooking zone. This speed typically varies from a few centimetres per minute to several metres per minute depending on the applications. The speed setting allows the cooking time to be precisely adapted to the characteristics of each product and recipe.
Concept of cooking zones
A continuous cooking tunnel is divided into several independent functional zones. The infeed zone allows products to be loaded onto the conveyor at room temperature. The preheating zone ensures a progressive rise in temperature to avoid thermal shocks. The cooking zone(s) maintain the temperatures necessary for core cooking. A drying zone (optional depending on the products) allows for the evaporation of residual moisture. Finally, the cooling zone progressively brings the products back to a temperature compatible with subsequent packaging operations.
Key control parameters
The main parameters controlled by the operator include the temperature per zone (independently adjustable), the conveyor belt speed, the type of energy used (electric, mains steam, natural gas, or LPG depending on the installation), air circulation (fan flow and direction), as well as steam injection in certain zones if necessary.
Example of product trajectory
Take the example of a ready meal in an aluminium tray. The product enters the tunnel at 15°C on the conveyor. It first passes through a preheating zone at 80°C for 3 minutes, then enters the main cooking zone at 180°C for 12 minutes to reach the required core temperature of 75°C. It then passes through a finishing zone at 160°C for 2 minutes, before entering a cooling zone where the temperature gradually drops to 40°C in 5 minutes. The product then exits the tunnel ready to be packaged.
Advantages of a cooking tunnel for the food industry
Homogeneity and reproducibility of cooking
One of the main strengths of a food industry steam tunnel or forced air tunnel lies in its ability to guarantee constant quality batch after batch. Every product undergoes exactly the same temperature profile for the same duration, which eliminates the cooking variations observed with discontinuous ovens. This reproducibility translates into a significant reduction in rejects and an improvement in the organoleptic and sanitary compliance of the finished products.
High throughput and continuous production
Unlike batch ovens that require loading, unloading, and cleaning times between bakes, the tunnel operates in a continuous flow. This characteristic allows for high production capacities, generally ranging from 200 kg/h to several tonnes per hour depending on the equipment dimensions and product type. Uninterrupted production integrates perfectly into modern automated lines in the food industry.
Optimised energy efficiency
Modern industrial cooking tunnels are designed to minimise heat loss. Reinforced wall insulation, independent management of each heating zone, and heat recovery from flue gases allow for optimised energy consumption. The power of each zone is adjustable based on the actual needs of the recipe, thus avoiding the energy waste observed with oversized ovens operating at partial capacity.
Product flexibility and adaptability
The same tunnel can be configured to process different product ranges through recipe settings. Zone temperature settings, conveying speed, and cooking modes (dry heat, steam, mixed) can be easily saved and recalled. This flexibility allows manufacturers to diversify their production without investing in multiple specialised pieces of equipment, thereby reducing investment costs and floor space requirements.
Integration into automated lines
Cooking tunnels integrate naturally into continuous production lines. Upstream, they can be fed directly by depositors, thermoformers, or filling equipment. Downstream, they interface with blast chilling, deep-freezing, or packaging systems. This integration allows for the creation of complete, highly automated lines, reducing manual intervention and improving the overall productivity of the workshop.
Selection criteria for a food cooking tunnel
The choice of a cooking tunnel represents a significant investment that must be carefully considered. Several technical and economic criteria must be taken into account to select the equipment best suited to your needs.
Target production capacity
The first question to ask concerns the desired throughput. Do you need to produce 300 kg/h, 1 tonne/h, or more? For products in trays, what rate in units per minute are you aiming for? These data will determine the dimensions of the tunnel, primarily its length and the width of the conveyor belt. Under-sizing will limit your growth, while over-sizing will lead to unnecessary investment and operating costs.
Types of products to be cooked
The nature of your products directly influences the technological choice. Meats generally require forced air cooking with precise core temperature control. Ready meals in sauce may require gentle steam cooking. Breaded products require dry cooking to maintain crispiness. Vegetarian products based on vegetables or legumes often require mixed profiles. Clearly identify your current and future ranges to choose the most versatile technology.
Desired cooking mode
Dry heat, saturated steam, forced air, infrared, or a combination of several modes? Each technology offers specific advantages. Forced air provides homogeneity and versatility. Steam preserves tenderness and allows for simultaneous pasteurisation. Infrared provides speed and browning. Mixed systems offer maximum flexibility but represent a higher investment. Your choice will depend on your priorities between organoleptic quality, yield, flexibility, and budget.
Quality and sanitary constraints
The food industry imposes strict hygiene and traceability standards. Your food production tunnel oven must meet several requirements. Homogeneous cooking guarantees that core temperatures required for microbiological safety are reached. Hygienic design facilitates cleaning with stainless steel materials, rounded corners, and the absence of retention zones. Cleanability is achieved through easy access, side doors for intervention, and potentially Clean-In-Place (CIP) systems for critical zones. Traceability of cooking parameters must be ensured by recorders or supervision systems.
Energy performance
Energy represents a major operating cost. Several aspects should be considered. The type of energy available on your site: do you have sufficient electrical power, mains steam, or natural gas? Each source has its advantages in terms of cost and performance. Modular heating zones allow for the optimisation of installed power according to your recipes. Good thermal insulation reduces losses. Heat recovery systems improve overall efficiency. Ask for projected energy balances to compare solutions.
Footprint and integration in the workshop
Cooking tunnels are bulky pieces of equipment. Their length can reach 15 to 30 metres depending on the application, with a width of 2 to 4 metres and a height of 2 to 3 metres. Check compatibility with your available space, ceiling height, and maintenance access. Modular design generally allows for several sections to be assembled to adapt the total length. Also, consider upstream (raw material supply) and downstream (finished product evacuation, packaging) logistical flows.
| Tunnel Type | Main Energy | Typical Products | Main Strengths |
|---|---|---|---|
| Forced air tunnel | Electric / Gas | Ready meals, meat, vegetables, desserts | Cooking homogeneity, fine time/temperature adjustment, versatility |
| Steam / pasteurisation tunnel | Mains steam / Boiler | Tray-packaged products, sauces, sensitive products | Simultaneous cooking + pasteurisation, texture preservation, tenderness |
| Hot air / infrared tunnel oven | Electric / Gas | Biscuits, crackers, snacks, pizzas, bread | High production, constant quality, controlled browning, crispiness |
| Mixed combined tunnel | Multi-energy | Diverse ranges, complex products | Maximum flexibility, multi-product adaptation, independent zones |
Moulds and accessories for cooking tunnels
The efficiency of a food production cooking tunnel also depends on the quality of the moulds and supports used during the cooking process. These complementary pieces of equipment play a decisive role in the final appearance of the products, line productivity, and ease of use.
Silicone moulds for intensive use
Maé Innovation, a recognised expert in silicone moulds for the food industry, offers solutions specifically designed to integrate perfectly into production lines equipped with cooking tunnels. Our professional-quality silicone moulds have essential characteristics for intensive industrial use.
Resistance to extreme temperatures is one of the main strengths of Maé moulds. Capable of withstanding thermal ranges from -40°C to +280°C, or even more depending on the formulations, they adapt to all cooking profiles encountered in tunnels, whether forced air, steam, or infrared cooking. This thermal resistance guarantees exceptional durability even in intensive use with repeated cycles.
Easier demoulding after cooking represents a major benefit for productivity. Thanks to the natural non-stick properties of food-grade silicone, products are easily released without the need for additional fats or release agents. This characteristic simplifies operations at the tunnel exit, reduces manual intervention times, and limits the risks of breakage or deformation of delicate products.
Adaptation to continuous production lines is a fundamental criterion. Maé Innovation moulds are dimensioned to fit perfectly on the conveyor belts of cooking tunnels, respecting standard widths and allowing for an uninterrupted continuous flow. Their design allows for maintaining a high rate while guaranteeing the dimensional consistency of the products.
Comprehensive expertise in baking supports
Beyond silicone moulds, Maé Innovation masters a complete range of solutions for cooking tunnels. Glass fibre moulds offer an alternative for certain applications while maintaining good thermal properties. Baking trays in various materials (perforated, solid, coated) complete the range to adapt to all types of products: biscuits, pastries, bread, ready meals, desserts, snacks. This global expertise allows for supporting manufacturers in the choice of supports best suited to their production and product quality constraints.
Frequently asked questions about cooking tunnels
What is the difference between a tunnel oven and a steam cooking tunnel?
A tunnel oven primarily uses dry heat (hot air, forced convection, or infrared) to cook products, while a steam cooking tunnel uses saturated or superheated steam as a thermal vector. The tunnel oven is better suited for products requiring browning, drying, or crispiness (biscuits, roasted meats, snacks). The steam tunnel is preferred for gentle cooking, pasteurisation, and sensitive products where texture and moisture must be preserved (sauced dishes, vegetables, certain meat products). Combined tunnels also exist that integrate both technologies to offer maximum flexibility.
What is the impact on energy consumption compared to a batch oven?
A cooking tunnel generally offers better energy efficiency than a batch oven for high-volume production. The main gains come from the elimination of repeated preheating and cooling cycles, better thermal insulation of modern equipment, independent management of each heating zone which avoids unnecessary overheating of the entire oven, and the possibility of recovering heat from flue gases or exhaust air. On significant continuous productions, savings can reach 20 to 40% of energy consumption per kilogram of cooked product. The initial investment is admittedly higher, but the energy return on investment is generally fast in intensive production.
Can a tunnel be used for several different types of products?
Yes, most modern cooking tunnels are designed to process different product ranges thanks to the customisable recipe system. You can save several cooking profiles with different temperatures, conveying speeds, and heating modes. Changing production is simply done by recalling the corresponding recipe on the control interface. This flexibility has some limits, however. Products must have dimensions compatible with the belt width. Cooking modes must remain consistent with the tunnel’s technology (a steam tunnel cannot make products crispy). Product changes require cleaning to avoid cross-contamination, especially in the case of allergens. Using adapted moulds, such as those offered by Maé Innovation, greatly facilitates this versatility by allowing different formats to be cooked with the same durable supports. Within these constraints, the same tunnel can typically process 5 to 15 different recipes depending on its configuration.
What is the average lifespan of an industrial cooking tunnel?
With regular care and rigorous preventive maintenance, the lifespan of a well-designed cooking tunnel can reach 15 to 25 years. The stainless steel mechanical structure is particularly durable. Elements subject to wear such as conveyor belts, conveying chains, electrical resistors, or gas burners require periodic replacement (every 3 to 7 years depending on usage intensity). Electronic and automation systems may evolve or be modernised after 10 to 15 years to benefit from new supervision technologies. The initial manufacturing quality, usage intensity, and maintenance reliability are the three decisive factors for the equipment’s longevity.
What are the advantages of silicone moulds in a cooking tunnel?
Professional silicone moulds, such as those developed by Maé Innovation, offer many advantages for use in industrial cooking tunnels. Their resistance to extreme temperatures (-40°C to +280°C and above) allows them to withstand all thermal profiles without degradation. Easier demoulding thanks to the natural non-stick properties of silicone improves productivity at the tunnel exit and reduces rejects. Their flexibility allows for moulding complex shapes while maintaining excellent mechanical strength under intensive use. They are compatible with all types of cooking (forced air, steam, infrared) and integrate perfectly into continuous lines. Their lifespan, superior to traditional metal moulds, makes them a profitable investment. Finally, food-grade silicone meets the strictest health safety standards for food contact, an essential criterion in the food industry.
A bespoke mould project for your production line?
Maé Innovation designs and manufactures silicone and glass fibre moulds and baking trays perfectly suited to your tunnels and production lines. Benefit from our expertise to optimise your productivity and the quality of your products.
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