Under the current circumstances, it has never been more important to look into ways to increase efficiency in bakeries, starting with their centerpiece: the tunnel oven. Mindful technology innovation is here to provide benefits in efficiency and sustainability. Baking a vast range of high-quality products is only the start of what cutting-edge tunnel ovens can do.

Oven preferences are different on each side of the ocean: while European bakeries favor product flexibility, high-capacity oven systems are preferred in the US. Electrically heated ovens are also more in demand in Europe. However, all markets and technology developers share one common priority for oven improvements: sustainability.

Hydrogen innovation: AMF

For AMF Bakery Systems, innovation in tunnel ovens means focusing on sustainability, primarily looking into energy efficiency and minimizing carbon footprint. As bakeries all over Europe are turning to electricity, AMF can turn its gas-fired Den Boer oven into an electric one, with several other solutions for modular electric baking.

The newest development has already made a name for itself and earned awards for innovation in sustainability: the Multibake® VITA Tunnel Oven by AMF Den Boer is a direct-fired oven, with hydrogen-fueled burners. It comes in various configurations: it can have grids for pans, mesh belts for hearth products, and stone plates for pizza, flatbread and a large variation of bread products. The versatile Vesta oven is suitable for baking trays for almost any product baked in a tray or tin. Lex van Houten, Regional Marketing Manager at AMF explains: “AMF Vesta Vita Hydrogen-heated tunnel ovens can bake any product that is normally baked in a natural gas-heated oven. AMF is able to offer customized solutions for many baking processes, for sustainable future-proof bakeries with net-zero emissions.”
Configurations are based on the type of products and the (current and anticipated) desired production rates. A stone-baked pizza will require significantly different conditions than a croissant, for example. The requested specifications will influence anything from steam and convection to impingement and moisture control. And the list continues. “That is why AMF teams and engineers all have a background in bakery and/or processing, so they know the right questions they need to ask and the advice they should provide to customers, to determine together the most advantageous configurations,” van Houten underlines.

Given a ‘to-bake’ list of multiple products, this oven is designed for flexibility based on the primary, most demanding product, and including elements identified after reviewing the whole product list in detail, to cover all bases. Based on this analysis, additional features can be added, such as extra top heat, bottom convection, infrared burners, or extra exhausts, to name some.

Resulting configurations of the Multibake Vita Tunnel Oven can comprise loading systems, infeed modules with exhaust hoods, steam modules for creating crust and color, multiple convection modules, modules with higher density burners on the top or bottom of the baking chamber, discharge modules, and even cooling modules. Later upgrades, when needed, entail simply adding modules to address higher production volumes or/and additional product ranges.

Heavy-duty baking
The AMF Vesta Tunnel Oven a is heavy-duty, high-capacity tunnel oven with lengths of up to 63 m, making it ideal for products requiring longer bake time or higher density. This oven has built-in grid hearths specifically for pans and trays. “It has a robust steam zone to condition products, and options for redundant drives, exhaust, and combustion blowers. It features the patented Guardian Chain Management System with predictive lubrication, and maintenance alarms,” van Houten details. The Guarding Chain Management System stores the length of the main grid chains at installation and keeps a log of the chain’s length every time the oven starts and stops. It also incorporates independent pneumatic-hydraulic tensioning systems that use minimal pressure to tension the chain and allow the chain to cool without tension. Low tension on the chains also facilitates the lubricant’s flow into the chain bushings.

The Vesta Tunnel Oven comes with standard bottom burners and optional top burners and a complete Coloraider convection system, which consists of fans and tubes that collect heat from the top of the baking chamber. This heat circulates through a series of delivery tubes fitted across the baking chamber, above and below the product zone. “The main ducts are adjustable to direct the heat to the top or the bottom of the oven. In addition, the outlets of the tubes can be rotated to direct the airflow towards or away from the pans,” the specialist details. The number of Coloraider zones is relative to the length of the oven, each having its own fan and 25 to 30 tubes.

“Its efficiency has been improved with better monitoring of the exhaust and the addition of AMF Sustainable Oven Service Technology,” van Houten highlights.

Another efficiency feature is the Direct Spark Ignition (DSI). AMF uses custom-built DSI for all its ovens. The Vesta Tunnel Oven, along with its sister the Vesta Tray Oven, are built to operate 24 hours per day for decades.

Baking smart and smart baking
The AMF Sustainable Oven Service technology monitors all of the functions of the oven, tracking temperature, airflow, occupancy, gas consumption and fan vibration, and logging the data for analysis. “With this information, AMF makes solid recommendations that can improve combustion efficiency, even heat distribution, product color, and more,” he details. In the future, the AMF Mixer Guardian System will be able to provide information to the oven for automatic adjustments, based on mixing energy and dough temperature, AMF anticipates.

For future developments, AMF is looking at alternative and sustainable heating sources that are the best match to the specific market: “Countries with plenty of electricity may choose all-electric ovens, or even hydrogen heated ovens, or both. Countries with limited electricity generation and distribution may choose natural gas, propane, hydrogen, or a blend of different fuels,” van Houten explains.

What should be expected from AMF ovens going forward? He anticipates: “We will continue to develop more of our ovens modular that can reduce installation time and costs up to 80%. We will keep on developing turnkey systems that are scalable for the future.”