Time isn’t on bakers’ sides. Growing pressure to increase throughput and product variety has them scrambling to get as many items out the door as possible in the shortest possible timeframe.

“Bakers are being forced into versatility,” said Dennis Kauffman, director of thermal products, AMF Bakery Systems. “Consumers don’t buy the same white bread week after week; some try rye bread, and some buy whole wheat.”

As modern consumer demands increase and become more immediate, turning up the heat isn’t an option to speed up the clock.

“You can’t just say, ‘If I push more heat, more BTUs, more energy into the product, I can just make it faster,’” said Shawn Moye, vice-president of sales, Reading Bakery Systems (RBS). “You have to determine the correct thermal platform and the baking curve for specific products.”

Time and temperature are no longer the only factors to consider. Variables such as moisture, heating type and airflow also bring opportunities for bakers to gain more control over the smallest details and dial in the process for precise and efficient baking.

“Today, we understand how, through chemistry and thermodynamics, we can intentionally and effectively deploy our heat tools to produce baked foods of any mass or mixture of ingredients and on any ratio of surface area to volume,” said Scott McCally, president, Auto-Bake Serpentine, part of the Middleby Bakery Group.

With clear product specifications and an open mind, bakers can employ parameter controls to unleash new — and seemingly endless — possibilities for efficient baking.

“The oven you bought 30 years ago was designed for one product; now, you make seven different products,” Mr. Kauffman said. “If you outfit it with different burners for energy efficiency, or if you set up different ­controls for automation, that’s where you can teach an oven to do new things.”

Beginning with the end

Before bakers can determine control settings on an oven, they must first define the product specifications.

“When a customer comes to us for a new oven, there’s a certain amount of information we need,” said Russell Garland, president, Advantech.

Understanding the finished product is the first step in determining how to make it.

“At some point within a range, the product dictates what you do in the oven, whether it’s time, temperature, moisture or any other feature of the machine,” Mr. Kauffman said.

A common misconception often has been that some ovens are only built for specific products. But Mr. Kauffman suggested reconsidering that notion.

“Many bakers believe that certain ovens don’t make certain products,” he said. “My challenge to them is to guess how the bread competing with theirs is being made. Not everyone uses a tunnel oven, so your loaf of bread could be sitting next to one that’s made in a totally different type of oven.”

The process in any oven — whether it’s baking a loaf of bread, a bun or a cookie — looks like an arc, or an S-curve, when achieving the final specifications. The bake must start out slowly to set the shape and size, followed by the moisture migration and finally the crust development and coloration, but every product type requires its own combination of the three to reach that perfect final outcome.

But no matter the combination, the order remains the same. For example, early crust development or case hardening — the result of high heat too early — will prevent moisture migration and not only risk burning the outer crust but also under-baking the center.

“An optimal combination is important for homogeneous color and browning and for the consistency of a crunchy crust and fluffy crumb,” said Richard Breeswine, chief executive officer, Koenig Bakery Systems.

In such a subjective process, the product is the constant.

“With our ovens, even with variable zones and dampers, we’re trying get the product where it needs to be — the spread, size, diameter and weight — we’re simulating baking a product the old-fashioned way,” Mr. Garland said.

Then again, bakers such as co-manufacturers don’t always have the luxury of knowing what the next product will be in their portfolio.

“That’s a bit of a challenge for us because we have to design a baking system that’s going to last 25 to 30 years,” said Kevin Knott, technical sales manager, Franz Haas Machinery of America. In this case, hybrid ovens that combine direct gas fire and convection offer flexibility for producers who don’t necessarily know what is on the horizon.

“They have more levers to control the finished product parameters such as size, taste or moisture,” he explained. “At the end of the day, it’s really not about what the oven looks like; it’s about what goes into the package.”

Feeding the machine

An oven isn’t a dumb animal, but it certainly is a hungry one.

“An oven likes to be full,” Mr. Kauffman advised. “And it likes to be steady. So, whatever the rate is, the oven just wants it to be uniform so it can react appropriately to what you’re asking it to do.”

For smaller and mid-sized operations that load the oven hearth manually or by using peels, lining up and spacing out the different products to achieve a consistent mass can do the trick, said Damian Morabito, president, Topos Mondial.

“By keeping the pounds per square feet the same on a given square foot area on the hearth, a baker can make fewer adjustments on the S-profile,” he said.

Mr. Kauffman also suggested that loading enough pans in a continuous run to prevent large gaps will help keep the oven from stopping and starting the heat.

But oftentimes, especially in an automated line, gaps can’t be avoided. In this case, it’s important to have an oven burner with a good turndown ratio to keep the temperature even and the machine running steady.

“A high quality, precision and efficient burner is very useful to the baker when it can go to a very low fire or a very low flame and maintain it,” Mr. Morabito said of Topos’ indirect-fired or cyclothermic J4 oven. “So when there’s less load in the oven or when the product changes, the burner isn’t going on and off; you can modulate it to a very low burner setting and maintain better control in your oven.”

AMF’s tray, tunnel and continuous ovens also have a high turndown ratio to keep the heat even.

“When a product is coming toward a heat source, it has to react,” Mr. Kauffman observed. “The reaction time comes from the controls, and when the oven knows what’s coming, it helps the burner react. This is important because when you have skips or gaps, you need to turn the heat down to avoid burning the next product.”

Because AMF manufactures complete system solutions, it is able to set up oven controls to best respond to the product being made and ensure that the oven is uniformly fed.

“We’re in a unique position that we can size our systems from the mixer all the way through post-packaging,” he said.

Eliminating flash heat is the key to ensuring consistency.

“In the old days, bakers would run water pans through the oven to get rid of the flash heat,” said Nathan Stockton, sales manager, CH Babb. “But with our stainless steel oven design, and the oven’s inherent low emissivity rate, you can get repeatability even if the oven has been empty for an extended period of time.”

A low emissivity rate also reduces the chance of over-baking from uneven heat distribution.

Running consistent product is also important in rack ovens, said Bruce Gingrich, vice-president, sales, WP Bakery Group USA.

“If you are using a rack oven, you should bake full racks of the same size, time and temperature items,” he said. “Mixing sizes will result in uneven baking, regardless of the oven quality or the controls.”

Dialing in the details

Back in the day, bakers who focused on temperature didn’t think about the “why” behind it. They didn’t need to; many of them were trained to have a hands-on approach to nearly every aspect of the process, so they could simply touch the dough or eye the final product and adjust the temperature from there.

Today, modern technology allows bakers to fine-tune nearly any baking variable, and some of these controls make temperature a relatively smaller piece of the puzzle.

For example, RBS employs what it calls “energy mode,” in which the process bakes to energy as opposed to temperature. This method uses the BTUs required for proper moisture removal from the food.

“The traditional baking method is temperature, but energy mode focuses more on the gas flow,” Mr. Moye explained. “With this mode, if a burner were to go out in an oven, the PLC is programmed to recognize that and compares it to the pressure in the air manifold and opens the air valve a little further to keep the new required volume of combustion air through the burners.”

In essence, baking to fuel flow increases efficiency because it eliminates much of the operator interface … and the potential error that can come with it.

Controlling airflow is another way that bakers can perfect this process. To help achieve this, Gemini Bakery Equipment Co.’s indirect-fire tunnel ovens are equipped with a vertical turbulence system.

“Variable speed airflow is reversible top-to-bottom or bottom-to-top,” noted Ken Johnson, president, Gemini. “This results in uniform hearth product bake and uniform pan product bottoms and side walls.”

Because moisture removal is at the essence of the oven’s function, dialing in moisture control is a critical factor.

“If you know how much moisture is in the product — or the oven itself — you can predict the moisture level in the food and get better uniformity and even shelf life,” Mr. Kauffman suggested.

AMF offers a feature for baking by moisture or humidity, which gauges the water vapor inside the oven.

“When you know what that level is, you can get the product weights right, and it’s the same every single day,” he said.

Mr. Knott said humidity control is a relatively new practice, especially from a cost standpoint.

“It’s more available to bakers today than it was 10 or 15 years ago,” he said. “Now, we can measure the number and actually control the moisture in the bake chamber to set a repeatable number for a more consistent product.”

Mr. Stockton agreed that maintaining proper humidity is on the forefront of the latest benefits in oven controls.

“Humidity has become more important, as to the grams per kilogram of water in the air,” he said, “because it enhances the transfer of heat into the product itself as well as assisting in controlling or stabilizing the pre-set oven parameters, and it could actually change the parameters.”

Damper controls also have become a more readily available oven feature. Bakers used to tinker with the damper to stick with a standard temperature, but now they can fine-tune those settings for enhanced control over moisture.

“Controlling positioning of dampers and other mechanical adjustments typically made by operators drastically reduces the possibility of human error,” Mr. Johnson said.

And it’s not just about the moisture that’s coming out of the food. Inserting steam into the oven can affect the look and texture of the product, especially for hearth-style artisan bread.

“How to distribute the steam, when and how to deliver it, and how to control the steam zone has evolved over the years to where the baker has a lot more control to get the crust the way they really want, over the way it was done in the past,” Mr. Morabito said.

By injecting steam into an oven via distribution piping, misting or sprays early in the S-curve, bakers can control the expansion of artisan products’ crusts like Kaiser rolls or hoagie rolls.

“We have a steam curtain — a physical curtain — to block the steam and keep it in a particular zone if the baker so desires to do that,” Mr. Morabito said. “Or for some products, the baker might want the steam to migrate down and burn off to give the product a nice bloom and shape.”

Conversely, using steam at the end of the cycle adds a sheen to the finished product.

“Some of our customers use a mister or spray at the discharge end of the process to give it a beautiful shine,” Mr. Morabito observed.