Raising the bar

by Emily Buckley
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Milling equipment suppliers have a very close working relationship with millers — and it is clearly evident in millers’ satisfaction with new milling technology (see article on 46). Diligently, suppliers strive to raise the bar, slowly evolving the age-old milling process to offer millers increased market profitability and potential. We talked to a few long-time suppliers to see which developments they think have been most influential on milling, as well as how feedback from millers drives innovation.


Globalization has to a large degree evened the levels of sophistication of mill facilities around the world. But regional differences still influence suppliers.

"While the global milling industry can be diverse, as the world in general becomes wealthier and more cosmopolitan, the differences in global milling become smaller," said Gerald Richardson, president of CETEC, the North American representative for Ocrim. "Cases in hand are China and the Far East, both of which 20 years ago had antiquated milling technology, and today by and large have technical expectations similar to those of North America or Europe."

Buhler still hears varying concerns from millers in different regions. The driving forces are the type and quality of the raw material available as well as the market demands. In some areas, the first priority is to supply sufficient nourishment to the people, whereas in other areas, high-quality and customer service are the millers’ top requirements, said Martin Schlauri, Managing Director of Milling and Baking at Buhler AG. "Hence, the achievements of milling engineers are valued differently," he explained.

For industrialized countries, he said, the key developments were complete mill automation, quality assurance equipment (online and loop control), and top sanitation in all aspects of the plant.

Yet worldwide, millers benefited from inventions for reduced production costs and lower maintenance, lower energy requirements, reduced personnel costs and higher yielding equipment.


Meeting maintenance and quality demands and creating new market potential have been key drivers for suppliers. Schlauri noted many specific developments from the last few decades, including cleaning machines with air recycling systems combined with functions to save space and as well energy, intensive scouring for better surface cleaning to reduce bacteria and mold; online automatic moisture measuring and control systems; and integration of color sorting systems for maximum cleaning.

He also commented on the rollermill developments, with double-high models, self-contained roll packs, gravimetric feeding devices, swing-out feed modules and rollermills with hinged covers for easy maintenance and sanitation. And thanks to new techniques in sieve motion and aerodynamic design of the air channel, purifiers have improved.

Markets for millers have expanded with the new processes for adding value to flour, such as mixing plants for premixes and flour heat treatment plants.

"The main drive from the customers are the words ‘ultimate purity and quality’ to prevent image losses and consequential damages," Schlauri said. "Equally important is increasing varieties of flours for new applications, offering value-added sectors even for non-food applications, reducing production costs in all aspects, and providing ultimate sanitation."

Schlauri said millers have also requested Buhler develop flour treatment to replace chemical additives or chlorine treatment, which are considered health hazards in many regions. In addition, millers have requested mixing systems to supply specialized flours to customers, addressing the needs of increasingly sophisticated and specialized bakers.

"A further request has come up for the removal of fungus-contaminated wheat to reduce the mycotoxin levels," Schlauri said.

Ocrim has seen similar driving factors, primarily in three areas, Richardson said. "The first area is automation, which reduces human error and analyzes data to improve performance and prevent losses. The second is equipment sanitation." In response to these, Ocrim has developed its @mill modular automation and management suite and its range of Inoxline stainless steel processing equipment. "Lastly, customers want to minimize downtime by increasing the interval between scheduled maintenance stops for machinery," he explained. "While modern materials and manufacturing components have helped in this, careful attention in the design stage of both plant and machinery are key in achieving this goal." He added that new equipment will almost always enhance a mill’s success because it is specifically designed to function longer between service intervals.


Satake has observed bakers’ demands as a driving force for millers. Bryan McGee, Special Projects Executive at Satake U.K. said that as bakers in developed markets strengthen their brand identity, quality issues become more important for the miller. McGee said the PeriTec process is gaining support among millers in the U.K. as a means of enhancing bread quality.

The new generation of vertical cereal processing machines has had a big impact on milling operations due to their greater product uniformity and resistance to choke blockages, he said. They were initially designed for rice pearling and then developed for maize degerming and wheat debranning. "Quality-driven markets are moving more towards debranning as a means of not only reducing mycotoxins, but also improving baking qualities of the flour," McGee said.

All of these methods have improved end-product quality for the baker. Yet Richardson sees another area where bakers are demanding improvement: consistent flour moisture.

"While we have succeeded in getting wheat of constant moisture in a mill, we have not succeeded in getting flour of constant moisture to a baker, Richardson explained. There are many reasons, he said. Primarily, moisture loss through the milling process can’t be controlled because we cannot economically control the climactic conditions within a mill. Compounding this is the fact that pneumatic conveying also dries the flour.

"This not only means that the miller doesn’t sell the optimum yield of flour he could obtain, but also that the baker starts with a constantly varying moisture level

in his flour, thus varying the consistency of the dough.

"The answer is to add moisture to the flour," he said. "But, there is a feeling that water may constitute an additive in flour, and thus have to be declared on the bag, along with wheat. If this could be ruled a part of the process and not the addition of an ingredient, both millers and bakers would undoubtedly benefit. In many parts of the world this is done with great success."

Several suppliers also noted color sorting technology’s potential to greatly increase end-product quality for the baker, while adding sophisticated cleaning and another level of quality control for the miller.

"Color sorting has had a big impact on quality standards in rice mills and will be adopted by wheat millers as capacities increase and component costs fall," McGee predicted. "Color sorting is now a viable alternative to classic mechanical sorting of grain prior to milling."


Across the world, millers have also benefited from improved sifting designs. Sifting designer Great Western Manufacturing, said that its customers have certainly driven its innovations over the years. The common themes among its requests are improved quality assurance methods and improved safety for the plant personnel, said Bob Ricklefs, sales manager.

In response, Great Western designed a sifter to be directly inserted into a pneumatic conveying line as a quality assurance tool for removing remaining oversized impurities at a stage closest to the customer, for instance at the end of a conveying line running to bulk truck/rail loading or immediately prior to packaging. This also allows the elimination of equipment, such as cyclone receivers, airlocks, receiving hoppers and blowers, which would be required for a standard atmospheric pressure sifter.

"We believe the In-Line Tru-Balance sifter is a truly innovative machine not only for millers but their customers as well," Ricklefs said. "The costs for purchasing, installing, cleaning and maintaining extraneous equipment is eliminated.

Complimenting the new sifter designs is the introduction of sieve cloth stretching equipment and new binding techniques that have dramatically improved the efficiency of the sifting operation.

According to Sefar, which specializes in manufacturing sieve cloth for processors, pneumatically stretched screens have a controlled tension that allows for consistency across the entire sieve surface. "With the use of cyanoacrylate adhesives on quick-change trays, the miller is able to stretch and glue as many as 14 screens in one hour, greatly reducing down time," said Mike Branson, product manager for Sefar’s North American division. "Adhesives also secure all of the threads, not just the stapled areas, and the sanitary bond eliminates the threat of insect infestation. As a result of these advantages, all of the major sifter manufacturers have standardized their new sifter constructions to include glue-on style frames."


Suppliers and millers clearly have a very close working relationship. But German supplier Vibronet has a particularly unique relationship since it has also been operating a mill in Lahnau, Germany since 1938. The mill produces 120 tonnes per day of wheat, rye and rice flour, delivering to both small and wholesale bakeries. Vibronet said most of its product ideas were invented while trying to run its mill as efficiently as possible, in regards to costs, hygiene and personnel.

Dieter Graf, who both supervises the mill and is head of Vibronet, speaks as both a miller and supplier. "All our inventions are first tested here in daily operation and only then brought to the market," Graf said. He finds particular benefit in Short Milling Diagrams that reduce investment cost, energy consumption, maintenance and personnel needs.

Graf also points out the great importance of tempering and moisture control advancements that shorten the temper time, reduce bacterial number, increase total yield and save energy. It also increases flexibility in production by allowing special millings possible within hours.

The biggest change he has witnessed in milling is the online quality control monitoring techniques. "Online intake control measures protein, moisture, temperature and specific weight for added quality control throughout the processes to guarantee uniform and optimal end-products," Graf explained. "Optimal production control and quality assurance are prerequisites for an economical production with highest quality standards. This requires reliably measured values of all process-critical parameters."

Graf said he primarily hears requests to further simplify the milling process so that a mill could be "handled just as easily as a dishwasher," with ability to turn it on and off and to choose a program.


These innovations have all worked together to evolve the milling process. In the end, Martin Schlauri focused on the overall mill process. "It is not an individual piece of equipment that brings success to millers," he said. "Milling is a sequence process in which each individual piece of equipment must fit the process technology applied, and each piece of equipment must be of equal quality and standard, as every chain has the strength of its weakest link."