I had an interesting discussion recently with a fish nutritionist about the use of black soldier fly larvae (BSF) as a potential fishmeal replacement for the aquaculture industry. The conversation was very engaging and led us down an interesting path of debate and enlightenment about this topic. I thought I would share with you some highlights and offer you a chance to reflect and hopefully comment on the topic- so please feel free to respond to the post.

My initial point to this individual with regards to the BSF industry was focused on the "good" the system presents to the environment. The idea that BSF can be used to recycle food waste and produce protein. Doing so, keeps these wastes from entering landfills and potentially polluting the environment. The system appears to have many strengths as it takes something of potentially no value and converts it to products of value. Of course, BSF represent a key product as it has been shown as a potential fishmeal replace for diets of fish grown in aquaculture. 

What I learned (informed) is the use of the term "replacement" is not appropriate as the nutritional makeup of the BSF is not equal to fishmeal. This did not come as as surprise to me. But, I did learn I need to me more careful with the language used to describe BSF products and their value. I am still not sure what the appropriate term should be - but I will definitely be more careful with describing the value of the product. 

​As a side note, I also would like to point out BSF fed brewery waste are higher in some of the key components needed in fish diets (e.g., higher protein and select amino acids such as methionine), while having lower fiber content. Furthermore, where brewery waste can spoil if not used quickly- BSFL produced from the system can be stored. Furthermore, BSF can take heterogenous materials and create a homogenous product where nutrients are concentrated.

The second learning point from this discussion is spent brewery grains can be fed directly to some fish or other aquaculture species grown in culture (I included a few references for your review). These materials can be a partial "substitute" for select ingredients.  The key word here is "some" as it cannot be generalized across all fish species. I do not say this as something that is new to me but rather as a reminder to be more cognizant about the language I use and to avoid generalizations. Be specific, do not generalize, and be concise and clear with the language used when talking with others.

A Few Papers to Read:
Incorporation of brewery waste in supplementary feed and its impact on growth in some carps

Pito brewery waste as an alternative protein source to fishmeal in feeds for Tilapia busumana

New developments in aquatic feed ingredients, and potential of enzyme supplements

Third, education is critical for creating opportunities for the BSF industry. While many of us recognize the value of the BSF to the world, many are still not aware of the potential of this system and what it means to the various commodities (e.g., aquaculture, poultry, or agriculture in general as related to compost). So, we all should take the time to start the discussion with learning more about what others know before launching into benefits of the system. Patience and education are vital to gain acceptance and advance the science.

Fourth, we still have a lot of work to do.  I really enjoyed the discussion and learned a lot from it. Most importantly, I recognize even more the need for conducting research, building partnerships, and expanding the BSF industry beyond entomology.  Experts from other fields bring so much to the table and should be engaged and invited to join the effort for deciphering all aspects BSF. 

I thought I would share this experience with you as I came to the realization that such interactions are important for everyone to be aware of (talking amongst ourselves simply creates an echo chamber of agreement)- and that the industry still has a ways to go towards acceptance. I welcome the challenge and look forward to working with those accepting, or not, of the capabilities of the BSF industry to impact the world in a very positive way.

I came across this paper this morning while looking for another paper on a  completely different topic (insects as feed for rabbits- I will explain later).  But, what a surprise!! I believe this paper is open access, which means everyone should be able to read it.

Nogales-Mérida, S., P. Gobbi, D. Józefiak, J. Mazurkiewicz, K. Dudek, M. Rawski, B. Kierończyk, and A. Józefiak. Insect meals in fish nutrition. Reviews in Aquaculture 0.

So, why do I like this paper so much?

• The authors provide context as related to insects as a natural feed for fish (really nice table summarizing across insect species and provide references).

 

• They provide an assessment of protein and lips content in insect meal.

 

• I am probably wrong, but I believe this is one of the most extensive reviews of insect meal in aquaculture strictly speaking from the amino acid perspective. 

 

• The authors provide a review of all amino acids as related to published literature on nutritional aspects of insect meal across insect species.

 

• They also provide a great table listing studies that used insects of some sort as fish meal for a number of aquatic species ranging from turbot to rainbow trout. 

 

• Issues with nutritional imbalances in diets provide to fish- great summary detailing why such research is critical for the insects as feed industry.

 

• Fatty acid content of five insect meals provided as well as citations

Periodically, articles are published that provide an overview of the BSF and its use in waste management. In many cases, information presented is a rehash of previously published material in books or other review articles. So, it can be challenging to locate the unique information presented. Now, don't get me wrong. I appreciate any and all papers published on the topic as they all serve a purpose in terms of education and perspective given.

But with regards to today's post.... every now and again, a unique article (a nugget of gold) comes along that I think provides some unique assessments of the BSF as related to a given topic. This paper does exactly that:

Kumar, S., S. Negi, A. Mandpe, R. V. Singh, and A. Hussain. 2018. Rapid composting techniques in Indian context and utilization of black soldier fly for enhanced decomposition of biodegradable wastes - A comprehensive review. J Environ Manage 227: 189-199.

This paper provides some very detailed assessments of the BSF for waste management and where it fits in the current paradigm of BSF industrialization. They provide a general overview of composting (e.g., vermiculture) in general as well. And, they take it a step farther and offer information on current patents (limited overview) currently on BSF technology. 

I highly encourage everyone to read this paper if available to you.