Lumpy, bumpy breakthrough
May 1, 2015
by Laurie Gorton
It’s not your father’s Oldsmobile when it comes to depositors today. The machines that portion doughs, batters and fillings have changed to accommodate preparation of the inclusion-rich cakes, cookies and sweet goods — and savory pastries — that consumers hanker after. New designs and servo technology aid their accuracy and reliability, improving payback ratios as well.
“Consumers today want more exciting products with multiple colors and funny shapes,” said Rick Parrish, director of sales and marketing, Franz Haas Machinery of America, Inc., Richmond, VA. “They want tasty products with many flavors. And a new machine that offers high weight accuracy often gives the [baker] a short payback period.”
That goes for the fillings, too. “Consumers want more filling in their pastries,” said Jerry Murphy, president, Rondo, Inc., Moonachie, NJ. “They want the authentic mouthfeel of the fruits, vegetables and meats, not an undefined texture or taste. We had to improve our depositor to handle higher quantities of fillings and bigger pieces.”
Andrea Henderson, Rondo Heritage vice-president of sales, noted, “Even sliced apples in fillings are getting to be bigger pieces.”
Clearly, market trends favor better-than-ever fillings and finished baked foods. “Bakers need new depositors that allow them to respond to consumer-driven trends by offering value-added new products that incorporate premium, wholesome and healthy ingredients,” observed Stewart Macpherson, vice-president, sales and marketing, Unifiller Systems, Delta, BC. Gluten-free doughs also affect depositor performance, he added. “They present a new set of issues for wholesale bakeries,” he said.
Another challenge is the snackification of muffins, cupcakes and brownies, accomplished by turning them into miniature two-bite treats. The small size of the pan cavities responsible for shaping these baked snacks requires different depositing manifolds, noted Robert (Bob) Peck, vice-president, engineering, E.T. Oakes Corp., Hauppauge, NY. “I see a trend toward more mini-style products,” he added.
But above all, depositors need to be speedy and accurate. “Owning a semi- or fully automated depositing system will often increase product sales by enabling the baker to meet high demand at peak seasons,” Mr. Macpherson said.
And these machines must achieve such results without altering the desired product, noted John McIsaac, vice-president, strategic business development, Reiser, Canton, MA. “People want the quality of the product out of a depositor to be the same as they get out of the mixer,” he said.
Servos on the job
To help bakers handle changing market demands, many equipment manufacturers have applied servo technology to depositors. The now routine use of servo motors to replace air cylinders in powering depositor functions provides several benefits, according to Lance Aasness, executive vice-president, Hinds-Bock Corp., Bothell, WA.
Servos facilitate ease of use, he noted, by allowing operators to enter a product name or SKU code into the control terminal. All settings are implemented instantly and repeatable. “This can lead to higher overall yield because the depositor can be making saleable product more quickly than conventional air-powered systems,” Mr. Aasness said. Deposit profiles can be readily tuned to alter speed, acceleration and deceleration, thus reducing splashing and tailing. Servos are also quieter than air cylinders and don’t require compressed air, thus saving utility costs.
The presence of inclusions in doughs and batters may result in slight weight fluctuations in the finished product. “Depositors equipped with a servo-driven flow divider achieve consistent batter flow and even distribution of inclusions during depositing,” said Cesar Zelaya, bakery technology manager, Handtmann, Inc., Lake Forest, IL.
Servo-controlled metering pumps on the V60 depositor from Franz Haas minimize pulsations in dough flow, according to Mr. Parrish. “Constant dough pressure across the pump house is a key component to achieving high standards of weight accuracy,” he noted. The system also minimizes the distance doughs must flow from the feed rolls to the measuring pump, thus maintaining uniform pressure in the cavity above each of the metering pumps.
The benefits extend beyond accuracy, according to Neil Anderson, director of business development, Axis Automation LLC, Hartland, WI. “Servo-driven systems provide consistency,” he said. “[Bakers] told us they needed to increase production speeds without compromise. Quick and easy changeovers, often requiring no tools, allow flexibility in applications and speedy access for sanitation and maintenance.”
The need to maintain piece integrity inspired early designs of a number of depositing systems, and their manufacturers continue to build on that legacy. The Vemag system from Reiser, for example, got its start handling and scaling mixtures with large inclusions. Recent improvements enhance those capabilities.
“We added larger double-screws to our small machine lineup,” Mr. McIsaac explained. “This improves piece identity without sacrificing weight control.” The company also augmented attachment options, thus increasing flexibility. “A recent visitor to our customer center came in to test a depositor for her inclusion-laden fruit cakes,” he said. Wanting to try a new product, technicians swapped in a different attachment that handled the new dough with the same degree of accuracy on the same base machine but in a completely different shape.
Risco USA Corp., South Easton, MA, invented a pumping technology that carefully maintains variegated texture in high-inclusion masses. “The roots of our company are among Italian sausage makers,” said Paul Kean, Risco’s vice-president. “The basic machine was developed for processors who wanted to show clearly visible lean and fat components; they don’t want them smeared together.”
This pump does not “roll around” or compress pieces as they move through the system. “When the dough comes out, there is no smearing of chocolate chips or crushing of nuts,” Mr. Kean observed. Improvements for the Risco depositor include a clean cut-off system and higher machine speeds through a redesign of the depositing head and a new actuating technology.
Patented vane-cell technology in the Handtmann depositor is gentle on inclusions in batters and cookie doughs, Mr. Zelaya noted. “It can properly process doughs and batters containing large inclusions such as blueberries and chocolate without breakage or smearing,” he said.
Another style of depositors uses pistons to deliver portions of batter or dough, and there’s been progress in this category, too. Franz Haas, for example, developed a new set of pistons for its MPRD depositor to accommodate particulates. “Inclusion size, of course, depends on the size of the deposit,” Mr. Parrish explained. “A special ‘cutting piston’ ensures no ingredients are blocking the in- or out-feed. If pieces are present, they will be cut.”
How mixtures travel through the depositor matters as well. Mr. Aasness described the Hinds-Bock depositor’s large product flow path. The company engineered the depositor with smooth, blended internal radii and positive shut-off spouts that accommodate particulates.
Physical dimensions and roll gaps require change to manage inclusion-rich cookie doughs. “Larger inclusions require larger gaps between the feed rolls so the inclusions pass through with minimal damage,” David Kuipers, vice-president, sales and marketing, Reading Bakery Systems, Robesonia, PA, explained. But he cautioned, “Larger inclusions reduce piece-weight accuracy.”
Pump, meter, release
The heart of a depositor is its pump. This technology, too, has been under pressure from the new generation of sweet goods and pastries. Depositor manufacturers reported improvements.
“The design of the V60’s metering pump gear teeth are optimized to ensure gentle handling of large inclusions in the dough mass without destroying them,” Mr. Parrish explained. This depositor uses positive displacement lobe-rotor dosing pumps that impart a low pulsing flow to provide accurate metering across the conveyor and in each row. To stop dough flow, the pumps reverse to create a vacuum, resulting in a uniform finish to the product with no tailing.
New for these machines is multi-port metering capacity. Mr. Macpherson described the Unifiller MultiStation depositor as “an all-around workhorse.” The volumetric system is fully computer-controlled to deliver speed, volume, flow pattern, deposit delay, cut-off and pre-charge via pre-programmed recipes controlled by a touch-screen terminal.
Flow dividers ensure even distribution of dough across the width of conveyor belts or pans. Mr. Zelaya described how Handtmann coupled its VF-620 depositor with its FS-510 servo-driven cutter mounted on a cantilevered frame. This setup can produce as many as 250 cuts per minute with a blade or wire.
Depositors can even deliver dimensional effects. Used to create filled wafers, the Franz Haas MPRD has the ability to move in three planes. “The X movement is the direction of the wafer displacement, the Z movement is an up-and-down motion, and the Y movement is crosswise to the direction of the wafer displacement,” Mr. Parrish explained.
If the pump is a depositor’s heart, then its manifold is its fingers, controlling the location and shape of the deposits. New approaches to manifold design have already opened new product development options for aerated batters.
“In cake depositing, there’s been a lot of activity,” Mr. Peck said. As more and more bakers add mini-muffins and bite-size cupcakes to product offerings, their depositors must hit smaller and smaller pan cavities. Finished mini products can be 1 to 2 in. in diameter; regular cupcakes are usually 2½ in. in diameter. “We had to make the depositor a lot more accurate. So, we developed different manifolds to accomplish this,” he explained.
To address this need and to reduce waste, Oakes designed a specialty slider valve. “It drops deposits straight down with a very clean cut-off,” Mr. Peck said. The valve severs batter flow, permitting no tailing.
Accuracy requires good process control, and Mr. Peck suggested tracking consistency through X-bar control charts showing upper and lower limits for deposited weights. “Check deposit weights often,” he advised, “and adjust the manifold distribution valves when necessary.”
Accuracy starts with the processes ahead of the depositor, according to Piet Vader, sales manager USA, Tanis Food Tec, Lelystad, The Netherlands, which is exclusively represented by Naegele, Inc., Bakery Systems, Alsip, IL. “Only when you have full control over parameters such as viscosity, pH, density, capacity, temperature and crystal structure will you be able to deposit within the narrowest range possible,” he said.
Mr. Vader recommended a change in batter preparation method, stepping away from batch systems in favor of in-line aeration. He described a system that controls batter temperature through use of scraped-surface heat exchangers and by insulation of the process to avoid ambient influences from room temperatures and humidity.
Match the depositor to the product, Mr. Vader advised. “Avoiding high shear, mechanical stress and vacuum in the depositor will lead to density control,” he noted.
Both high and low extremes in viscosity present difficulties in depositing. “Attention needs to be paid to heavy, viscous and difficult-to-handle materials,” Mr. Anderson said. Several models of the Comas depositors represented by Axis address such problems.
Gluten-free is no cakewalk, either, according to Mr. Macpherson. “The biggest challenge is that some gluten-free batters have very high viscosities,” he said. “It sometimes can be a challenge to maintain accuracy when drawing the product into the metering chamber and then placing the product where you want it and getting clean cut-off.”
Fillings rival batters and doughs in their diversity, and depositing systems designed specifically for fillings are being adapted to those differences. “Fillings are costly, and therefore, overdosing of filling reduces the margin significantly,” Mr. Murphy said, stating the case for automation as a guarantee of high weight accuracy.
Rondo recently re-engineered its Rondofiller, a universal filling system, to make it more flexible by offering screw, piston and, most recently, Moyno pump capabilities. Mr. Murphy outlined the differences in filling methods. Mechanical depositors work best for creamy to semi-viscous, self-flowing filings, and pneumatic depositors best suit soft to firm fillings with small pieces of fruits and vegetables. “The universal filler gently applies all types of filling,” he noted. “Pieces of fruits, vegetables or meat are not damaged on application.”
Like inclusion-rich cakes and pastries, fillings today are getting chunkier, whether sweet or savory. “The trend is to hand-held products for eating on the go,” Mr. Murphy said. “The stromboli, for example, is an interesting new application, essentially a sauce, cheese and meat mixture inside a folded or rolled dough piece.”
Ms. Henderson added, “The Rondofiller easily handles flowable liquids like tomato sauce that may also include chunks of cheese, pepperoni, sausage and other such ingredients. We’re also seeing a number of Indian food applications. Those fillings often include peas, and you have to handle them without destroying their texture. We knew we had to modify our existing equipment.”
In today’s bakery manufacturing environment, accuracy is essential. While consumers may treasure the minor variations that characterize handmade goods, strict packaging regulations demand uniform weights. Such accuracy can dictate semi- or fully automated methods.
The manufacturers interviewed here noted accuracy requires a systems approach and careful engineering of individual components. “The systems are engineered to finite tolerances,” Mr. Anderson said. “The accuracy is designed and built into the machine. Once set up and commissioned, the [baker] can be confident that when he presses ‘start,’ the machine will perform consistently and repeatedly with almost zero interruption.”
Accuracy also depends on up- and downstream conditions. That’s the reason most depositor manufacturers engineer their machines to be part of complete processing lines. Risco is the latest to take this approach. “We have a lot of customers who are going from hand-scooping their doughs to bringing in a depositor and the associated systems to feed it and the oven,” Mr. Kean explained. “They don’t want to be the integrators of such lines, so we are doing it for them. We also integrate with other equipment manufacturers.”
What’s the best way to keep depositors running at their peak accuracy? “Benchmark the equipment,” said Sam Pallottini, die product sales manager, Baker Perkins, Grand Rapids, MI. “You should always benchmark the performance of a new machine, when the rolls, dies, harp and frame are new. All components wear over time. If you properly benchmark a new machine, you can determine what wears and how quickly, so you can replace those parts before they affect performance.”
In the end, it’s basic maintenance that’s an absolute requirement. Mr. McIsaac reported that Reiser has worked to make maintenance an easier task. “Also, we fully train the operators and the folks who work on the machine when we install it.”