The need for dedicated pilot plant infrastructure for insect rearing and processing: a case-study from Belgium

Insects have the potential to form the basis of a sustainable value chain that plays a key role in the transition to a biobased economy. Numerous companies recognize the potential of insects, but immediate application on an industrial scale is hampered by several obstacles such as regulatory uncertainties and the need for support to upscale their processes. Another challenge is that only limited information is available on industrial insect rearing, and the information that is freely available often comes from small-scale research. Translating the research findings of that small-scale research to industrial scale is often cumbersome. In Belgium, KU Leuven and Thomas More in collaboration with VITO started doing research on insect rearing and processing about a decade ago. They recognized the need to add expertise on pilot scale, aside from their research on laboratory scale, as an intermediate step towards industrial production. The realisation of the Insect Pilot Plant in Belgium has enabled their ambition to offer such solutions at pilot scale. Additional benefit of having this pilot facility is that increased reliability and flexibility that comes with it enables the standardisation of all experiments, lab-scale as well as pilot scale, further increasing the expertise of the research centres involved and their ability to transfer that expertise to the sector.


Introduction
As the world's population continues to grow and society gains a better understanding of our impact on the environment, there is an increasing demand for alternative and sustainable protein sources (Henchion et al., 2017).In terms of these alternative proteins, plant and fermentation-based products currently gain most attention.Yet, insects are also emerging as a promising alternative (Bashi et al., 2019).Several insect species are capable of converting low-value organic side streams into high-value biomass that can be used as feedstock for food, feed, and technical applications (Van Peer et al., 2021).Although the use of insects for food and feed has a long tradition in many countries, it did not receive attention in the Western world until the turn of the century (Van Huis, 2022).
The production of insects for food and feed is growing rapidly across the world.More than 1 billion euros have been invested in this sector and investments are expected to reach 3 billion euros by 2025 (IPIFF, 2021;Pippinato et al., 2020).Today, about one hundred com-panies operate in this sector in Europe which produce over 6,000 metric tonnes of insect meal annually (IPIFF, 2021).By 2030 the total production capacity of the European insect sector may reach 1 million metric tonnes of insect meal (IPIFF, 2021).Simultaneously, research on insects as food and feed is also increasing.More than 80% of all peer reviewed scientific articles on this topic were published during the last five years (Van Huis, 2022).These figures show that this new sector is thriving, although at the same time, due to the very fact that the insect sector is still in its infancy, many challenges still remain.
In Belgium, research on rearing and processing of insects for food, feed and technical application started about a decade ago.In 2016, 3 institutions (KU Leuven, Thomas More University of Applied Sciences and the Flemish Institute for Technological Research (VITO)) all located in the province of Antwerp joined forces and applied for an investment grant to acquire dedicated infrastructure needed for rearing, harvesting, and processing of insects at pilot scale.The dossier was given the suitable name Insect Pilot Plant.The goal of the Insect Pilot Plant project was to increase the expertise of the research centres involved and facilitate the transfer of that expertise to the target groups.
In this opinion paper we discuss the realisation of the Insect Pilot Plant and its importance for insect rearing and processing.We will elaborate on the importance of conducting pilot studies and on the added value of this particular infrastructure.In addition, we also discuss how such infrastructure contributes to ensure that the obtained knowledge reaches the sector and helps it to move forward.

Need for pilot scale research
Most research published on insect rearing and processing involves small-scale studies.For example, insect feeding trials are often conducted with only about 100 insects in small trays with a surface area not being larger than 100 cm2, while industry often rears more than 10,000 insects in trays having a surface area of at least 2,000 cm2.It has been shown that such a difference in size has a significant impact on the results, and consequently on the usefulness of lab scale results for the industry.For example, for black soldier fly (Hermetia illucens, BSF) larvae, both growth and composition are influenced by the crate size in which they were reared (Yakti et al., 2022).Along with the latter, the temperature can be significantly affected by scaling since the area-to-volume ratio of the rearing tray is much larger on a small scale than on a large scale.As a result, heat transfer on small-scale will be more efficient than on a large scale.Moreover, at small-scall temperature can be manipulated to precise and narrow ranges, which is not achievable on an industrial scale (Wray et al., 2022).
A second important aspect is the scalability of techniques used within studies on lab-scale when upscaling.For instance, manual mixing of different side streams for example is no longer feasible when 500 kg of feed needs to be produced.Production of bigger amounts of insect feed requires the use of different equipment that might alter the physical structure of the obtained substrates (e.g.coarser texture), which in turn can alter larval performance compared to lab-scale research.Another example is the drying of insects.Lab-scale research often prefers freeze-drying as it has a minimal impact on the chemical composition of the insects, however the technique has clear limitation on its capacity and has a high energy cost (Hernández-Álvarez et al., 2021).Thermal, microwave, or radio-frequency drying are more scalable alternatives, however they all influence the quality (e.g.color or protein functional parameters) of the insects different (Melgar-Lalanne et al., 2019;Huang et al., 2018), especially when the batch size alters the duration of the treatment needed.Such effects are important to be taken into account and explored before translating lab-scale processing methods to industrial scale.

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Need for dedicated infrastructure One obstacle often encountered in research is the lack of dedicated infrastructure.For instance, food and feed safety are key in the production and processing of insects.To safeguard this, conditions and restrictions are imposed by the government.These must prevent unwanted contamination of food that poses a possible health risk to consumers.For insect rearing and processing, many overviews of the relevant risks and legislation have been made in recent years (Lähteenmäki-Uutela et al., 2021).Nevertheless, the novelty of the insect sector implies that major questions currently still exist on the relevance of the restrictions and conditions imposed by governments.Zooming in on the microbiological safety, the current European legislation for insects as feed (Regulation (EU) No 142/2011) encompasses criteria on Salmonella, Enterobacteriaceae, and occasionally Clostridium perfringens.However, it remains unclear whether these are indeed the most rel-Journal of Insects as Food and Feed 0 (2023) 1-5 evant risks to include in legislation.To answer this question dedicated infrastructure with both the adequate biosafety containment level (L2) and the approval to rear insects is needed, which does require to adhere to more requirements to avoid the escape of insects from the L2 biosafety facility for example.At the same time, the effective implementation of food and feed safety legislation for insect production is not always straightforward.A few organisations such as, for example, the International Platform of Insects for Food and Feed (IPIFF) and the Flemish Strategic Platform Insects (SPI) drew up a manual to help insect producers and processors to correctly interpret and implement the regulations in practice (IPIFF, 2019;Spranghers et al., 2021).But here again, the sector is in its infancy and there are almost no practical examples of good practices available as they exist already for other agri-food sectors.Having dedicated infrastructure would also allow research to meet the hygiene requirements as dictated in food and feed safety legislation.
Besides hygiene, sustainability is also an important factor in insect rearing and processing.Although this is often used as an argument to promote this sector as a sustainable alternative to conventional protein sources, apart from the use of side streams as feed, there is actually little research into, for example, energy consumption and greenhouse gas emissions during rearing and processing.These are parameters that are not only important for the image of the sector but extremely important information for companies when applying for environmental permits (Berggren et al., 2019).

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The need for comparability and the usefulness of research A smooth flow of knowledge and information between research and practice is needed to drive innovation in the insect sector.Dedicated pilot scale infrastructure allows for demonstration of know-how.For instance, for pigs, poultry and cattle, there are already numerous applied research and demonstration centres where results from small-scale applied research are tested at relevant scale and environment.These organisations provide translation of the research to the industry and vice versa, the need to investigate specific and industryrelevant knowledge gaps is passed on to research.Indeed, the research carried out should be relevant to the industry.In this regard a crucial role is reserved for organisations such as for instance the European IPIFF and the Flemish SPI, as they can foster interactions between industry, research and authorities.Besides the many techniques available in the plant, general bio-safety precautions were also taken into account in the design.For instance, all materials used can be disinfected and cross-contamination is avoided because the various processes carried out throughout insect rearing and processing do not come into physical contact with each other.One of the climate chambers is also equipped with a separate ventilation system specifically for rearing allergen-producing insects.This system prevents researchers from being exposed to these allergens through the air.The pilot plant also has two research labs, one of which is equipped and licensed as a containment level 2 laboratory (L2).This is a rather unique combination as it combines the permission to rear liv- ing insects with the use of biosafety level 2 (L2) microorganisms.It can thus be used for the investigation of foodborne pathogens during the rearing and processing of insects to update the legislation on the most relevant risks.
Today the Insect Pilot Plant is used for multidisciplinary research and demonstration projects in which the developed expertise is the basis to support interested research partners, companies, the government and the general public.
More information on the Insect Pilot Plant can be found on the website: www.insectpilotplant.be.
Journal of Insects as Food and Feed 0 (2023) 1-5 Downloaded from Brill.com 12/26/2023 11:03:27AM via Open Access.This is an open access article distributed under the terms of the CC BY 4.0 license.https://creativecommons.org/licenses/by/4.0/ As an example, IPIFF recently released a document in which they listed research priorities(IPIFF, 2022).Also, initiatives such as the workshop to establish standard methodologies for R&D at the Insects to Feed the World conference in 2022 organised by the Organisation for Economic Co-operation and Development (OECD), or the establishment of working groups on standardisation and insect nutrition of the Study Commission Insects of the European Federation of Animal Science (EAAP) are of crucial importance for the future success of the sector.