Hygienic design: No corners or cracks — the imperative importance of cleanliness in the food industry

There's more to today's food industry than the mass production of tasty and nutritious items. Whereas recent decades have seen major advances in production technology, the focus at present is very much on the topic of hygiene. From 4th to 7th April 2006, trade visitors from all over the world will be attending Anuga FoodTec, the International Trade Fair for Food and Drink Technology, where they can discover the most important innovations in this field.

In the past, hygiene in the food industry was largely a matter of experience, whereby a liberal use of cleansing agents and disinfectant often served to create a comforting and illusory safety margin. Today, however, the war on dirt and germs is a highly coordinated campaign waged with the weapons of science. Involved in the fight to ensure flawless and reproducible hygienic conditions are three mutually dependent factors: safety, shelf-life and cost. Although hygiene considerations initially require investment and generally necessitate extra planning when setting up new production facilities, such efforts ultimately have a positive impact on the bottom line. For if such issues are taken into account early enough, completely cost-neutral solutions can be implemented without further ado.

Recognition and elimination of risks
Each year, poor hygiene in the production of food leads to damages amounting to several billion U.S. dollars. The engineering industry is therefore committed to eliminating such sources of contamination. These almost always derive from design faults or negligence in the use of production machinery. Leaving aside the latter, it is the former that is the focus of what's termed hygienic design. This growing field of expertise combines a range of disciplines and is devoted to such tasks as the design of perfectly cleanable components, the right choice of materials and methods of processing them, and the installation of pipes and fittings that are self-discharging and free of dead space where deposits might accumulate.

Whereas the use of these types of components and fittings is really only common sense, other advances in this field - such as reliable biomonitoring - are the product of many years of experience and development. In order to impose some order on this complex and extensive body of knowledge, such advances in the hygienic design of components, processes and production machinery are now documented in national and international regulations and recommendations, which represent the latest developments in this field and are continually updated. This followed a period in which various sectors of the food industry conducted their own research in the field of hygienic design, which naturally resulted in a maze of different specifications. Today, however, certification according to recognised standards provides a major source of guidance for food manufacturers looking to evaluate machinery and components. As a result, it has become much easier to assess whether the criteria of hygienic design have been met and if equipment is suitable for everyday use.

Rules, standards and regulations
There is an immense complex of international laws, regulations, standards, organisations and authorities to regulate all the various hygiene issues in the construction of plant and production machinery for the food industry. These include - and such a list is no means complete - the European Hygienic Engineering Design Group (EHEDG) with its raft of guidelines; the stringent regulations of the U.S. Food and Drug Administration (FDA); the 3A Sanitary Standards in the dairy industry; the United States Department of Agriculture (USDA) and its regulations on the use of lubricants in the food industry; and the standards of the German Institute of Standardisation (DIN) along with those of the CEN, its European counterpart.

Meanwhile, organisations such as the German Engineering Federation (VDMA) have joined forces with the Industrial Organisation for Food Technology and Packaging (IVLV) as well as other partners in order to collate the knowledge available in scientific institutes and companies with a view to making it accessible to the industry as a whole. The idea here is to provide assistance with the search for relevant laws, regulations and standards as well as advice on how to implement them in practice.

Clean inside and out
The use of production plants and machinery designed and constructed entirely according to the principles of hygiene is becoming increasingly standard in the food industry today. This is also stipulated as a basic requirement in the EC Machinery Directive 98/37/EC. In many instances, weak spots are also being eliminated in older plant and machinery. On the other hand, no industrial installation operates in a vacuum, and by no means every process takes place completely in a closed system. Most products come into contact with the environment at some time or other, if only during filling and packaging. For this reason, and when it comes to avoiding cross-contamination, the spotlight now falls increasingly on the process environment. This generates a host of questions. In which direction do air currents flow in production premises? What are the walls and floor made of? Can lubricants or other production materials get into foodstuffs? How can contamination from the process environment and, above all, from production workers be avoided? After all, human beings continue to pose the biggest hygiene risk with regard to foodstuffs. At the same time, important insights have been gained into the actual conditions that obtain on surfaces involved in production. For example, our understanding of the origin, danger and resistance of biofilms and their interaction with different types of surface is improving all the time. In turn, this yields important knowledge for the development of effective and foolproof cleansing and monitoring methods for use in the food industry. Today, research is already looking for ways of implementing an online control of the hygiene status of production machinery.