Author: lalander

Over the last year, the BSF group has conducted exciting experiments as part of the Happy Salmon project. We received big batches of two species of macroalgae (Ulva and Saccharina) for the Nordic SeaFarm in Dingle, to be used as feed substrate for rearing BSF larvae. The algae was mixed with brewery spent grains, provided by Train Station Brewery in Knivsta and vegetable waste, ensuring a nutritiously balanced diet for the larvae. Interestingly, the larvae grew quite well in this blend substrate and achieved a high body protein (40%), while the fat content was considerably lower than our larvae usually are (< 15%), making this larval biomass a good feed ingredient.

The frass fertilizer obtained in these experiments also had interesting properties, having > 80% of organic matter and a NPK ratio of 3/1/3. However, the most exciting results regarding this frass fertiliser was the composition of beneficial microorganisms, stimulated by the presence of the algae in the larval diet.  Moreover, the frass container plant hormones,   including auxins, gibberellins and cytokinins, which are important regulators of plant growth and metabolism. These novel results are being investigated and assessed now to see how different plant species can benefit from frass when it is applied in the soil.

As a next step, the larvae produced with the macroalgae and brewery spent grains are being pressed and defatted, and then used as a nutritious feed ingredient for the production of fish feed. Skretting, a global leader in sustainable aquaculture nutrition, in Norway will use this feed in salmon growth trials. We believe that this BSF larvae-derived ingredient can be considered a more sustainable feed ingredient for aquaculture. Fingers crossed for interesting results to come!

The seminar is given in English and can be seen here.

On Thursday the 12th of September at 12:15 pm CET, Cecilia Lalander will tell her view on the matter. Tune in! It will be available online afterwards if you don’t have time to watch live.

Worth knowing is the SLU University Library’s popular science lunchtime lecture series. Here, exciting and recent research results from SLU are presented. We offer a light lunch, and after the lecture listeners have the opportunity to ask questions.

In our article Recirculating frass from food waste bioconversion using black soldier fly larvae: Impacts on process efficiency and product quality recently published in the Journal of Environmental Management, we showed that food waste-derived frass, an unstable fertilizer with phytotoxic properties when used fresh, can be reused in the bioconversion process as part of the larvae’s feed. This approach offers several benefits for both the process and the quality of the resulting larval biomass and frass fertilizers.

Several studies reported phytotoxicity (adverse effects on plant growth, physiology or metabolism cause by several different substances) in frass from black soldier fly larvae (BSFL), especially when growing crops in greenhouses and using frass as a fertilizer or growing media. We believe that this phytotoxicity is related to the fact that waste bioconversion with BSFL is very rapid (< 14 days), and that there therefore is no time for the organic matter to be stabilized. Stabilizing this “fresh” frass’ organic matter is crucial for its safe use as a fertilizer or soil amendment. However, studies have shown that the post-composting of frass can be the major source of greenhouse gas emissions and increase the overall environmental impact of this treatment. Finding a more viable and sustainable way of stabilizing fress frass was the main goal of this study.

The hypothesis of the study was that a significant portion of the organic matter in food waste-derived frass remains relatively undigested, allowing the BSFL to further consume and digest it, thereby increasing the degree of decomposition. This hypothesis was confirmed, as the frass produced after consuming the food waste with frass inclusion (called recirculated frass) had a lower organic matter content than the fresh frass. In addition, several characteristics of the recirculated frass pointed towards higher maturity and higher stability, which indicates that it is safer to use as fertilizer. Interestingly, not only the resulting frass, but also the larval biomass was positively affected with this frass recirculation process. A significant correlation of larval biomass composition and frass-inclusion rate was establisheda, showing that as frass inclusion increased, the larval biomass had higher protein content and lower fat content. Considering that protein ingredients are the most expensive input in animal feeds, this is likely to be of interest to the insect industry.

One of the most intriguing findings of this study was that recirculating frass back into the bioconversion process significantly increased the larval yield per unit of waste. This indicates that incorporating fresh frass into the larvae’s diet allows for a higher biomass of larvae using the same amount of waste. This innovative method for enhancing both the process and product quality is highly promising. We are now developing new studies on frass recirculation to better understand the underlying mechanisms and explore any additional benefits this approach may offer.

We are not even halfway through June, and we already have two major highlights to share.

On June 5th, the Ambassador of Japan, Mr. Noke Masaki, visited us. Björn demonstrated the urine diversion toilet and explained the benefits of urine dehydration technologies. The Ambassador then came down to the BSF container, where Cecilia gave a short presentation of the technology and our research on the topic. Ivã and Viktoria then guided our visitors through the BSF lab, answering questions about the rearing and fertilising potential of the flies and their frass.

A week later, a joint delegation from Kenya-Lycksele came by for lectures from Björn and Cecilia, followed by visits to the urin diviring toilet and dehydration system, followed by a tour of the fly container, where Viktoria showed the eager participants around.

Knowing that our technologies and ideas gain international interest keeps us motivated to continue contributing to a circular society.

On April 23rd, representatives of the EU ambassadors came for a visit to the ET Department and had a pe[e]k at our urine diverting toilet where Björn and Prithvi talked ab   out the future of urine dehydration and the potential it harbours.

After the toilet, the visitors went on to our Black Soldier Fly container were Cecilia, in bitter cold winds, shared our vision on how to contribute to a circular food and feed production, if food waste would get accepted as a feed source for insects.

The evening ended with a dinner at the castle in Uppsala where ideas and visions for the future were exchanged.

Last week, Cecilia and Viktoria embarked on a night-train journey to attend the grand opening of ENORM biofactory in Midjytland, Denmark. On the 5th of December, ENORM opened its doors and welcomed visitors to inaugurate Scandinavias biggest insect company. The long-term goal of  ENORM is processing substantial amounts of organics to produce equally substantial volumes of insect-derived products.

To say that we were impressed is an understatement, and we wish ENORM all the best with their endeavors.

If you want to know more, see their linkedin post of the event and an episode of Vetenskapsradion På djupet (in Swedish) in which they interview Jane Lind Sam, the founder of Enorm.

Evans Were has joined the Kretsloppsteknik group as a Postdoc Research Fellow. At SLU, Evans will investigate the mechanisms and dynamics of infectious biological agents, including prions, bacteriophages, and spore-forming bacteria in the process of bio-conversion of biowaste using black soldier fly (Hermetia illucens) larvae. Larvae of H. illucens remarkably convert biowaste into larval biomass (high-quality protein feed) and residue (biofertilizer) as end products. Understanding the dynamics of infectious biological agents within this process is crucial to ensure process safety and efficacy.

Evans worked as a technical assistant researcher at the Hans-Ruthenberg Institute, University of Hohenheim. There, he taught bench techniques (including microbiology and molecular biology) to graduate students. Before joining Hohenheim, Evans worked as a research assistant at the International Institute of Tropical Agriculture (IITA) in Uganda. At IITA, Evans optimized methods for molecular characterization of plant pathogenic microorganisms and supported phytopathology and plant breeding teams. This work led to the discovery of novel genetic traits that enhance resistance to some of the most economically important diseases of banana, a crop that provides food security and income for over 400 million people globally.

Evans was born and raised in Uganda, where he completed his diploma and BSc degree in Biological Sciences, and MSc degree in Molecular Biology from Makerere University. Evans earned his Doctorate in 2023 from the University of Hohenheim, Germany where he studied the notorious phytopathogenic fungus, Fusarium oxysporum f. sp. cubense tropical race 4.

Hi, our names are Ava & Evelina. We are two 17 year old girls in our final year studying Natural science (Naturvetenskap) at Rosendalsgymnasiet. For nearly three years we’ve been studying topics based around scientific subjects. Part of our studies consists of a scientific rapport, called a Gymnasiearbete (highschool diploma work), a requirement needed to graduate next summer. Throughout the next couple of weeks we’ll be doing laboratory work in the Department of Energy and Technology at SLU. We intend on focusing on the link between larvae and algae infected mussels from the Baltic Sea. We’ll be guided by Viktoria Wiklicky and Dr Cecilia Lalander who will help us in carrying out our studies.