There is a long history behind flour milling, which started when hunters and gatherers began using stones or mortars for crushing grains. With the increasing division of labor, the milling occupation to process wheat, rye or spelt came into being. During the Middle Ages, the milling profession in Europe came to be known as disreputable and dishonest because of all the possibilities for cheating. But in the 16th century, Reich law decreed that it was an “honorable” and “guild-worthy” profession.

Challenges for millers

Today, millers around the world, whether their mills are large or small, are important suppliers for many different food producers. Bühler has routine contact with its customers, hearing from mill operators about the changes that have taken place in their area of work over the past years, and how these changes affect their work and their needs in terms of mill expansion. There are two increasingly big challenges shared by customers. Businesses that process the flour are demanding increasingly higher flour quality and guaranteed consistency within narrow parameters.

Along with the growing product diversity, based on desires by consumers, which the mill’s customers have to offer, is the increasing demand for specialty flours. This confronts mill operators with the challenge of offering a constantly expanding range of flour products while maintaining consistent quality and keeping prices competitive.

Changing markets for raw materials

Our customers also report changes regarding their suppliers. International grain markets have changed significantly in the past 20 years. Up until recently, there were central export organizations to ensure standardized and clearly defined product qualities in the countries that export grain. However, recently the supply chain on the grain market has become fragmented.

This has an advantage for individual millers in that it allows their needs for grains to be freely covered on a large market. But, the reverse side to this is that the miller must deal with many different qualities of grain. If a miller wants to provide consistent flour quality, he needs to purchase cleverly and mix various raw materials together. Flour made from the same batch of grain is, for the most part, only possible for regional flour specifications or organic products. In addition, there is a global overcapacity of 30% to 40% in the milling industry, which puts pressure on price competitiveness. Of course, this overcapacity often is due to mills being located “in the wrong place” and/or in poor condition. This explains why demand for new mills is holding steady.

These changes and trends in the milling industry have a direct effect on planning and constructing new mills. To manufacture flours with consistent quality from varying raw materials — in addition to the quality of the plant components — a permanent monitoring of processes and products is essential. A growing number of sensors and software are assisting or even replacing manual control by the miller and help to guarantee as well as verify permanent quality.

Traceability for every single processing unit all the way back to the wheat field is possible in modern mills. The changed customer demands encountered by flour mills also entails additional plants for the storage of diverse flours and the blending needed for the desired products.

Building mills is still an adventure

The challenges in building a new mill also have changed. The biggest obstacle is not the actual planning of the mill but dealing with local and national officials that can lead to complications and/or delays in the permitting process for new plants. Although it is the customer’s responsibility to obtain the permits, Bühler, which has built mills for 150 years, is directly involved in the process as the project manager and as a supplier of the necessary equipment. But difficulties can arise anywhere between the permitting phase and the construction of the building’s shell and infrastructure by local contractors through to the plant installation and commissioning. Bühler has found that building a mill “anywhere in the world” is always an adventure because of the local circumstances.

Bühler Mill E3

Construction of a new flour mill is oriented to ecological and economical features. Customer requirements for mills must be taken into consideration just as much as the many legal regulations that demand compliance. In addition, increasing competition exerts pressure to improve product quality while lowering production costs.

The next generation of mills needs to enable production of market-conform flours at the lowest cost possible. The next generation of mills at Bühler is called “Mill E3.” This is a building shell made of conventional parts that is only three stories high and has correspondingly less building volume. This lowers costs for infrastructure.

The actual mill itself is assembled in the finished building shell using pre-installed and tested modules, which significantly reduces time and material for installation. These modules are built compactly and comprise mostly new, energy-saving plant components.

A new Mill E3 can be built in a short time. It requires less space and has a more economical total cost. And, thanks to energy-saving technology, it consumes significantly less energy per tonne of processed wheat. Just the energy for the grinding alone is reduced by 10%. The energy savings for the entire mill is 7% to 10% while, it must be noted, keeping the same parameters for yield and product quality.

Alternatives to grinding?

The basic principle of grinding has stayed the same for thousands of years: kernels are crushed into powder between two hard surfaces. Our researchers have tested alternatives and developed them to market maturity. But neither the use of lasers or ultrasound have yielded lab test results close to the pulverizations methods, and they were certainly not superior. Even a chemical approach using enzymes to dissolve the bran and crush the endosperm was proven to be less promising. There is still biotechnology.

The biotechnological conversion of wheat directly into bread or pasta is conceivable but still open for implementation. I don’t think consumers are ready to eat such bread or pasta. The trend seems to be moving in the opposite direction: Consumers want their bread as a natural product with as few unnatural ingredients as possible.

For mill builders, this means we must keep developing milling technology to make it highly efficient, compact, economical and easy to maintain, and to create mills that can monitor and optimize the process themselves. But experienced millers will never be redundant, even in such a modern mill. The miller will be the one who must determine the efficiency of production using his abilities and knowledge. Our plants will be there to offer increasingly resourceful support for his tasks.