By Allergen Bureau

In-depth knowledge of Hygienic Design improves not only allergen risk management but increases productivity and sustainability – a report by David Lowry, Chairperson EHEDG NZ Regional Section

In-depth knowledge of Hygienic Design improves not only allergen risk management but increases productivity and sustainability – a report by David Lowry, Chairperson EHEDG NZ Regional Section

Hygienic Design is a term often used in the food industry, but what does it mean exactly?

EHEDG, the ‘European Hygienic Engineering & Design Group’ defines Hygienic Design as “Design of components, assembled equipment, utility services and manufacturing plants to avoid contamination of foods with foreign materials and enable cleaning to an appropriate microbiological, allergenic or chemical standard.”

EHEDG Document #8: Hygienic Design Principles states:

“The fundamental reason for applying hygienic design principles is to prevent contamination of food products. Equipment and factories of poor hygienic design are difficult to clean. Residues (soil) may be retained in crevices and dead areas. Product residues allow micro-organisms present in the product to survive and multiply. Additionally, contaminants, e.g. foreign matter, allergens, lubricants, detergents and disinfectants, might be carried with the product during processing and packaging. The primary objective of equipment and factory design is to fulfil engineering functions. Sometimes the requirements of hygienic design conflict with the functionality. An acceptable compromise must never put the food safety at risk. It is more effective to incorporate hygienic requirements into the initial design, because upgrading an existing design can be prohibitively expensive and may fail. Benefits are not only product safety, but also the potential of increasing the life expectancy of equipment, reducing maintenance measures, enhancing sustainability and lowering operating costs.”

In many regards hygienic design is the foundation block on which allergen management is built for food manufacturing facilities. While hygienic design incorporates other HACCP pre-requisites in its scope, the primary consequence of hygienic design is on cleanability. No matter how smart and fit for purpose a cleaning and sanitation program is, it cannot be effective if there are areas where soils are entrapped and not readily accessible in the timeframe or with the tools available for cleaning.

Although an item of equipment can be designed in compliance with the design principles for cleanability, it may not be suitable for use with of all kinds of food (e.g., a pump used for liquids might be easy cleanable but used for liquids with particles might not be cleanable). Integrating hygienically designed equipment and factories is not a guarantee to achieve cleanliness to a pre-determined level (e.g., to an acceptable level, with respect to allergen protein levels). Depending on the food product (e.g., sticky, or viscous products), the important cleaning parameters: time, temperature, chemistry, and mechanical action, may need to be increased for successful cleaning. The intended use must be considered.

While most allergen product recalls are due to the presence of undeclared allergens caused by labelling errors, cross contact due to poor production, scheduling, poor equipment design and poor cleaning regimes between product changes is also a problem. Problems of allergen cross contact can be exacerbated when foods containing certain allergens are made on the same line as those producing other products that contain different allergens. This is where hygienically designed equipment that is easy to clean and effective cleaning regimes – especially during changeovers – is crucial. Cross contact is a risk that is increasing as manufacturers move away from lines and equipment dedicated to making just one product and use more flexible production lines capable of making different products. This level of flexibility is both desired and required to provide companies with the agility they need to respond quickly to changes in consumer demand for different products.

Changeover cleans are carried out for quality, integrity or safety. But whatever the reason, they need to achieve the right result, fast, and that can be hugely influenced by the design of the equipment. All too often, however, production demands mean that not enough time is allocated to thoroughly clean equipment between production runs, or incorrect detergents and procedures are used, potentially causing allergen cross contamination to be missed.

The right hygienic design is paramount to facilitate fast and effective cleaning of food processing equipment. Cleanability is a very important hygiene requirement independent of the cleaning methods, e.g. automatic or manual (including clean-out-of place (COP)). Improperly or insufficiently cleaned equipment is a potential allergen risk and cannot be effectively disinfected. Equipment and factories which are difficult to clean will require procedures which are more severe, using more aggressive chemicals as well as longer cleaning and decontamination cycles. Consequences are higher costs, reduced availability for production, reduced lifetime of the equipment and more effluent, i.e., productivity and sustainability outcomes.

The considerations involved in conducting hygienic design risk assessments and the detailed understandings relative to types of equipment and their integration in a process line requires training and education from an expert base. EHEDG provides that functionality through its product portfolio of subject matter Guidelines, expert Training & Education offerings, Equipment Testing & Certification programs, and extensive network of Global experts and practitioners available to members. The EHEDG Guidelines are science-based, developed by expert working groups representing all food safety stakeholders, i.e., food manufacturers, equipment and service providers, regulators, academia, and workplace Health & Safety. The Guidelines offer practical hygienic design rules for food processing buildings, food production environments, and a wide range of food processing equipment types and are regularly updated and added to, keeping pace with new technologies and food industry practices.

For more information on how to become a member of EHEDG and the benefits it offers – visit and/or feel free to contact David directly at the New Zealand Regional Section of EHEDG –