It’s the consumers’ new mantra: “Less is more, and nothing artificial is best.” Today’s trend that finds shoppers eschewing food additives affects more than just bakery formulating. It also alters the design and performance properties of dough dividers. To achieve clean-label status for their bread and rolls, bakers are taking out the chemical improvers, conditioners and other additives long used to give machining tolerance.
Those decisions put pressure on dough handling technologies, especially dividing, and every divider manufacturer reports efforts to achieve “dough friendly” design. Such engineering attention now shows results in machinery that promises gentle processing and product flexibility. Engineering changes also pave the way to computer integration of manufacturing.
But yes, the divider still has to do its job producing consistent product weights — to act as the bakery’s “cash register” by preventing costly under- and over-portioning. The changes are significant.
“The issue we see a lot is [bakers] want minimum dough punishment for high-end specialty products but also want the best accuracy possible,” said Mark Rosenberg, president, Gemini Bakery Equipment Co., Philadelphia. “Normally, two primary factors are important: weight accuracy versus dough-friendly dividing.”
The divider has a simple function: to portion dough accurately at the speeds required, observed Roger Romsom, marketing and sales director of Benier NL, a member of The Kaak Group, The Netherlands. “But in addition, it must maintain the quality of the dough delivered to it by the mixer. This is a discussion we have with bakers all the time. They want the accuracy and capacity but say, ‘Don’t change my dough.’ ”
Formula-related needs are clearly at the heart of divider design changes. Cesar Zelaya, bakery technology manager, Handtmann, Inc., Lake Forest, IL, pointed to factors such as the increased use of delicate inclusions that optimize premium value for the finished product, additions of grains and seeds prompted by consumer demand and the rise of gluten-free products — all products with doughs sensitive to over-handling. “Besides these needs, dividers need to handle dough with a very wide range of water content from very low to high absorption, from 40 to 80%,” he said.
The impetus for change was stated succinctly by Larry Gore, director, sales and marketing, AMF Bakery Systems, Richmond, VA. “Bakers said our dividers needed to be more flexible so they could run different doughs through the same divider. This has been our focus in recent years,” he said. This need prompted the company to develop its new AMF Flex Technology. “This flexibility allows the divider to perform optimally on many different yeast-leavened doughs from slack doughs like English muffins to stiffer doughs like specialty rolls,” he explained.
Improvements run the gamut. Servo technology has been a game changer, and greater adjustability characterizes control over compression ratios in ram-and-knife and piston dividers. Portioning capacity for extrusion dividers has expanded to encompass piece weights from 10 g to 10 kg. New divider feeding methods reduce the stress on high-absorption dough, and adjustable dough width capability has been added to sheet-then-divide systems.
“We are focused on improving divider technology through use of servos,” Mr. Romsom said. The Kaak Group is represented exclusively in the US by Naegele, Inc., Bakery Systems, Alsip, IL. Kaak Group dough specialists extensively studied what was happening within the machine and how to manipulate its conditions via the servos. “We put more intelligence into the machine to guide operations,” he added. “The machine collects data from the process to make the operation more transparent.”
The result was the Benier Dough Master. “The knowledge gained from applying servos to it also helped optimize our other dividers — the Benier Dough Expert and Benier Dough Assist — which are smaller-range machines. We made small modifications and achieved better quality and accuracy to improve the existing models.”
Mastering parts and uses
Changes have also taken place with the advent of removable components, exchangeable dough pistons and adjustable cams and vanes. For Koenig, these features help bakers achieve higher standards in sanitation and handle larger dough weight ranges with improved weight accuracies, according to Richard Breeswine, general manager, Koenig Bakery Systems, Ashland, VA.
“The Industry Rex AW, Rex Futura Multi and Mini Rex Multi were recently launched to address these concerns when producing pretzel, sourdough, pre-fermented yeast and various other doughs generally under 70% hydration,” he added, noting that the company’s industrial capacity dividers now accomplish ±1% weight accuracy.
Equipment manufacturers have expanded the range of materials used in divider construction. For example, Mr. Rosenberg described adapting the Gemini/WP divider’s SR model with a special material in the dividing box to meet the challenges of handling low-pH sourdoughs. Other design changes allow better access for improved cleaning and reachability, and reduced maintenance, he observed.
Ken Weeks, project manager, Kemper roll lines, WP Bakery Group, Shelton, CT, noted changes in construction materials that improve sanitation. By making dough hoppers of plastic instead of stainless steel, the company eliminated Teflon coatings that can wear and get into the product. Switching to blue-colored plastic instead of white follows up on the request from bakers wanting better recognition of tramp plastic. The company adopted Intralox belts to replace felt for the spreading conveyors that transport dough pieces away from the divider. “They are easier to clean and do not absorb moisture, which causes felt belts to mold,” he added.
Productivity gains exist as well because of higher throughputs and lower waste. “Proven benefits [from new dividers] on white bread can include up to 15% increase in cell count, up to 20% increase in softness, greater volume, improved crumb development and better color,” reported Keith Graham, marketing manager, Baker Perkins Inc., Grand Rapids, MI.
Sometimes, it’s a matter of building on proven designs to make them work even better. Such is the case with the Winkler WBD 100 bagel divider developed by WP Bakery Group. “We designed this bagel divider to run at 100 strokes per minute with a weight accuracy of ±1 gram,” said Patricia Kennedy, president. “This is done by the way we bring the dough into the divider and [by engineering] the drum to rotate completely to increase speed.”
Renewing volumetric methods
What exactly does “dough friendly” mean? Dividing is a volumetric process that cuts dough into pieces of consistent weight to comply with packaged goods labeling regulations. At a constant specific gravity, a given volume of dough should yield a given weight, but dough’s specific gravity decreases as it ages. Also, different formulas produce doughs of different densities.
“The principle of dividing is to take into the divider’s pocket only the amount of dough necessary to fill it and keep it in the same condition as it came from the mixer.” Mr. Romsom said. “This is the ideal, but in the real world, dividing can change the dough’s consistency. For some, this doesn’t matter; however, if your focus is on artisan products, you want to keep the cell structure intact because that’s what bakers tell us is responsible for the finished product’s taste and aroma.”
The push to improve accuracy has shaped the evolution of ram-and-knife dividers. “Weight accuracy can be achieved by compressing the dough to minimize the air bubbles or gas incorporated during mixing and or pre-fermentation,” Mr. Rosenberg explained. “The most important issue relates to the need to be able to adjust the amount of dough punishment from formula to formula. Products that need to be handled more gently with less stress are handled with less compression.”
The Gemini/WP divider is designed to control the amount of compression put on dough in the divider box and, thus, increase or decrease dough punishment to what it can tolerate. “Adjustable compression allows [bakers] to use the very minimum amount by lowering the pressure and reducing dough punishment,” Mr. Rosenberg said.
High-volume bakers have relied on ram-and-knife technology for many years. “These dividers offer great flexibility to bakers wanting to respond to increasing demand for greater variety in either standard or artisan style breads,” Mr. Graham said. Increasingly, this means working with doughs made with inclusions such as nuts, seeds and fruit pieces and few, if any, chemical improvers.
Additional changes also improve ram-and-knife dividing. Mr. Graham described a significant upsurge in output capacity to 10,800 pieces per hour. “This was achieved by redesigning the division box to incorporate an additional die and was done in recognition of a general trend toward higher-output lines,” he explained.
Sheeting dividers put the force of gravity to work to turn bulk dough into individual pieces. Released by gravity from the feed hopper onto a weighbelt, chunks of dough are joined into a continuous sheet and conveyed forward at a speed determined by their weight. The computer-integrated system signals the cutter assembly to portion accurate-weight pieces.
Matching of dough types is important with dough handling, according to a spokesman for Rheon USA, Irvine, CA.
The sheeting divider developed by Rheon handles no-time and long-fermentation doughs as well as very gassy formulations. The V4 Stress Free Dough Feeder at the front of a makeup line produces a continuous dough sheet, which is continuously weighted as it moves from the V4 to the makeup system and then cut for moulding or flat breads.
This method nearly always generates trim or scrap dough that must be recycled or discarded. To minimize the waste involved, Rheon USA introduced the Adjustable Width V4-Dough Feeder to its Stress Free makeup lines. The operator can adjust the width of the continuous dough sheet according to product specs. “This new technology allows a custom setting based on the width needed for products and helps reduce trim dough,” the Rheon USA spokesman noted. “The operators can manage the trim dough percentage for a wider range of dough types and product varieties to help control costs.”
Koenig adapted its patented TwinSat technology, developed for the company’s Menes dough sheeting system, as a way to feed dough into divider hoppers. It uses two satellite heads to eliminate stress during sheeting and dividing. “This new system improves the quality of high-end artisan breads while the various modular dividing components for cutting and shaping the dough add flexibility to produce all sizes of ciabatta, pizza and flatbreads, baguettes or loaf breads,” Mr. Breeswine said.
The company provides two different divider types: the Koenig Rex system for doughs with hydration of less than 70% and the Koenig Stress Free system for those over that level. “The Rex system gently divides dough with a slider block and piston system while the Menes stress-free line uses the TwinSat system,” Mr. Breeswine explained. “It’s the dough characteristics that determine the type of divider used to gently divide the dough and retain the cell structure.”
Refining extruder performance
Newer on the scene is extrusion dividing. Like ram-and-knife systems, these dividers convert bulk dough into a stream of individual pieces for further processing. But the way they operate is significantly different, and their evolution follows different avenues.
Seeking to improve dough handling, Reiser re-engineered the infeed system of its Vemag divider to cut down on imparted stress. “The heart of our machine is our unique double-screw portioning,” said John McIsaac, vice-president, strategic business development, Reiser, Canton, MA. Looking at the path of dough, the company opted for larger pockets in the screw system. “This has allowed us to make fewer revolutions per portion, reducing machine speed.” The company also evaluated the effect of vacuum and pressure, working to optimize both.
“We have also made advances with our control systems for more precise scaling,” Mr. McIsaac continued. “Our flow dividing for English muffins and rolls is [managed with] no valves, motors or throttle, just consistent even weights across four, six, eight or more lanes without additional force or controls.”
Taking a different approach, Handtmann employs patented vane cells to portion dough, and this system has been refined, too. This design “lets bakers easily adjust the cam and vanes as they wear so the divider can always stay on its original factory settings without the need to regularly replace components,” Mr. Zelaya explained.
In the bakery environment, this results in reduced downtime and simpler labor requirements for tear-down, setup and changeover, he said, describing savings as significant over the lifetime of the equipment.
Improvements in control technologies have also been made. For example, the Handtmann Communication Unit (HCU) has been integrated into its dividers. Mr. Zelaya described how this works. “[The HCU] checks individual piece weights against the standard and automatically makes any
extremely minor weight adjustments back to the exact target weight in the next dough pieces,” he said. Weight variations are less than ±1%.
Knitting things together
Dividers don’t perform in a vacuum; their actions must fit smoothly with increasingly fast processing lines producing an escalating number of product styles.
Decisions start with understanding the product and its process, Mr. Rosenberg explained. That includes “the whole process from mixing to dough processing to baking with all the relevant data of ingredients, process flow and the necessary flow times,” he said. “This is the basis for the definition of the right hardware.”
An essential factor is the treatment doughs get before dividing. “Dough hydration and dough floor time will impact the integration between mixing and dividing,” Mr. Breeswine observed. “No-time doughs are fairly simple to handle through an integrated system while higher hydration doughs with long floor time require some thought.”
Proper fit is important, Mr. McIsaac emphasized. “Once we are certain we can provide the best dividing solution, we configure the machine to give the customer the best combination of product quality and scaling accuracy,” he said.
High capacity must be accompanied by smooth operation and accurate piece weight. “A successfully integrated system is one that never allows the divider to run short of dough or to have a dough waiting in the mixer,” Mr. Graham observed. “The former obviously leads to a break in production, but before that [happens], a low head of dough in the divider hopper will lead to the production of a few lightweight pieces.” Keeping dough waiting in the mixer inevitably results in excess gas formation and lower density — all resulting in reduced piece weight. “Feedback from a checkweigher is used to automatically adjust the divider to compensate for this, but not before a few lightweight pieces have been produced,” he added.
Dividing should be seen in terms of the whole forming process, Mr. Graham advised. “While installing an Accurist2 on a line will lead to an improvement in texture, the effect can be greatly enhanced by using Baker Perkins rounders and Multitex4 moulders designed with the same principle in mind.”
Connecting via electronics
In the quest for efficiency, bakeries have become much more interconnected, and that aspect also affects divider selection. “More and more bakeries are moving to Ethernet communications,” Mr. Gore reported. “The setup from ingredient handling, mixing and dough makeup is often integrated into one communications network.”
Like all of its new equipment, AMF configures its dividers with recipe management for automated setup when switching from one product to another. “With the new divider designs, very few, if any, adjustments are made manually,” he added. “With today’s demands for variety, changeovers have a direct impact on performance and quality. With such communications, one input changes multiple operations instead of the operator having to make multiple setup adjustments manually.”
Equipment manufacturers typically build dividers as independent machines, yet they can be readily integrated into an ingredient handling or mixing system. “The bowl tipper of the mixing system normally has a proximity switch, which looks into the hopper.” Mr. Weeks explained. “When the dough reaches a certain level, this gives the signal to the bowl tipper that it can tip the dough into the hopper. No additional integration or other factors are required.”
Seamless integration with other equipment is the norm for modern dividers. “With line utilization and efficiency becoming more and more critical because of ever-increasing labor and construction costs, system integration and versatility are key decision factors,” Mr. McIsaac said.The market changes continually, Mr. Zelaya observed. “We’re finding that when bakers are evaluating new equipment now, they are spending even more time considering possible products they may need to produce in the future and trying to anticipate the demand those doughs may place on their equipment,” he said.