Lesson 6 - Hygienic Design

The main reason for applying hygienic design principles is to prevent any contamination of products. Poorly designed equipment and plants are difficult to clean and can either cause or contribute to the contamination of products.

If you are involved in any food manufacturing, there is a good chance that you have experienced the effects of contamination in some way or another. Hygienic design is primarily aimed at eliminating the risk of these contaminations. When it comes to cleanliness, your plant is either clean or it is not. Let us look in more detail at what hygienic design is and why it is so important.

What is hygienic design?

Hygienic design is the design, construction and installation of equipment in such a way that it does not adversely affect food safety or quality.

It may be easier to view hygienic design as the design of cleanability. Imagine your facility as a warzone. The enemy is contamination in any form. Your army is your cleaning regime. You want to design your facility in such a way that the enemy has nowhere to hide or to find a foothold. This will give your army the best chance of flushing out the enemy and driving them out of your plant. The more hygienic the design is, the easier it will be to flush out any contaminants completely, and the lower the cost will be on resources.

Why is hygienic design important?

The consequences of bad hygiene have been with humans through the ages. It is believed that Alexander the Great’s death in 323 BC can be attributed to typhoid, which is a food-borne illness. Food poisoning has been responsible for many deaths over the centuries. Modern statistics from the CDC (Centre for Disease Control in the USA) indicate that each year, approximately 3,000 US citizens die from food poisoning. We can clearly see that in modern times, food safety is of greater importance than ever before. What factors do you think have contributed to this?

Firstly, we are now producing food products in increasingly larger facilities and widely distributing them. This means that a greater number of people can be affected over a wider geographical area. Secondly, there is an increasing move away from preservatives and overly-processed food; therefore, the risks of contamination are far greater. Lastly, we are being exposed to new forms of bacteria at an increasing rate due to globalisation and the ease with which these bacteria can spread around the world.

It is important that we realise the hidden costs of poor hygiene. If a contaminated product is detected before it leaves the factory, there is the cost of manufacturing and destroying the product. If it has already been bottled, both product and packaging costs are incurred. However, if it has left the factory, the costs will include the costs for product recall and, even worse, the impact on the company’s reputation.

What is the difference between hygienic, ultraclean and aseptic?

The above terms are often used loosely. When it comes to hygienic equipment, it is important that we understand the difference between these terms.

Hygienic equipment is designed to be effectively, completely and reliably cleaned in place. Certification in this regard deals with the efficiency of cleaning. There is still a small risk of contaminants entering through the equipment seals.

Ultraclean equipment has a level of protection against contamination from the atmosphere or environment. Thus, there is an additional layer of protection built in. For valves, this can take the form of hermetic (air-tight) seals where the barrier zone can be sterilised by steam or other means.

Aseptic is like a bullet-proof approach to hygiene. There is a mandatory hermetic seal, and this zone is continuously sterilised.

The level required depends on the product being made. For products with a long shelf-life, aseptic may be required.

Let us now consider the history of hygienic design.