Interview With Bengt Eliasson, Chairman Of The EHEDG Working Group Heat Treatment On The New EHEDG Guidelines

Friday, October 26th, 2018

Rob Groot, EHEDG Consulting Writer at Tetra Pak, Sweden and Chair of the EHEDG Working Group Heat Treatment interviews Bengt Eliasson, Chairman of the EHEDG Working Group Heat Treatment for his views on the renewed EHEDG guidelines on the pasteurisation and sterilisation of liquid food.

Groot: We’ve been pasteurising and sterilising for ages. Why renew these guidelines now?

Eliasson: Pasteurisation and sterilisation are widespread and important methods to preserve liquid food. This is why the initial guidelines for continuous pasteurisation and sterilisation were the very first guidelines that EHEDG published back in 1992. Since then, new technologies and new legal requirements and regulations have emerged. EHEDG translates all those developments into practical guidelines that the food industry can actually work with. We also want to help EHEDG community members to find the information they need more efficiently. Therefore, all EHEDG working groups recently agreed to structure their guidelines in a new and more user friendly format that structures information into categories like design, production and maintenance aspects.

Groot: So what’s new?

Eliasson: The old versions of these guidelines focused primarily on milk production, thus limiting its possible applications. The renewed guidelines covers other liquid foods and high acid products like fruit juices. They provide practical technical frameworks that cover a wide array of topics ranging from general considerations to hygienic process design, effective flow diversion, re-circulation and cleaning and control processes. They help readers to make sure that correct temperatures and processing conditions are maintained, that unacceptable deviations in key process variables result in an automatic flow diversion or shutdown and that the production process is stopped before fouling becomes significant or before thermophilic bacteria growth becomes too intensive. These guidelines also provide useful information on techniques to optimise energy efficiency and minimise maintenance intervals.

Groot: You mentioned energy efficiency. How sustainable is hygienic design? 

Eliasson: Energy efficient solutions in general, and heat recovery techniques in particular, are becoming more and more important for food producers. Thus, they are willing to invest in new techniques to optimise efficiency. Food producers not only want to save energy, water and chemicals, but also to maximise their productivity by minimising cleaning time intervals and waste. Hygienic design offers many possibilities to save energy and minimise downtime. These guidelines contain several chapters that help EHEDG community members to make sustainable choices to minimise contamination risks and to save energy and money. The guidelines illustrate that investing in hygienic design solutions is economically viable. By applying hygienic design we can shorten CIP times, make the production more efficient by overall increasing availability and reduce the total cost of production. Since investing in hygienic design improves overall efficiency, it’s is a cost saving investment it. It also avoids recalls and public health hazards.

Groot: Is there a link between hygienic design and new foms of energy re-use?

Eliasson: The guidelines also illustrate how certain systems work, for example a system that enables producers to preheat their products by heat recovery using a secondary circuit. Heat recovery systems are in general more complex in terms of plant design but the results are very satisfying, because they require significantly less energy. Even when investment budgets are limited, these guidelines offer interesting options. In sterilisation processes for example, it’s also possible to preheat a product after the holding section with a sterilised product in a regenerative heat exchanger, making for a less complex plant design and realising the same amount of energy savings.

Groot: Were these guidelines were developed by food safety experts? If so, who are they?

Eliasson: EHEDG made sure that the heat treatment working group consists of top level technical experts from a wide variety of disciplines. It is a broad team with origins in different parts of the industry, ranging from equipment design to process management, maintenance and quality control. Combined, these experts represent more than 200 years of hands-on experience. This way EHEDG makes sure that the guidelines are technically thorough and contain a high practical value. After reading these renewed guidelines, the EHEDG community knows what to do and how to do it.

Groot: So it’s not the germs we need worry about then, it’s our inner terrain?

Eliasson: Exactly. And let me conclude with yet another quote of the great Louis Pasteur, who not only discovered the power of pasteurisation, but who also had a very clear vision on food safety in general: “whether our efforts are, or not, favored by life, let us be able to say, when we come near to the great goal, I have done what I could.”