Developing Future Aquafeeds and the Use of Insect Meal: A fishmeal perspective.

A few days after the insect farming workshop was held in Scotland, IFFO published an article in Fish Farmer.

Developing Future Aquafeeds and the Use of Insect Meal: A fishmeal perspective

As a start, it is probably useful to get some perspectives clear.  Perhaps surprisingly to the readers of Fish Farmer, IFFO, The Marine Ingredients Organisation, recognises the importance of, and need for, novel ingredients production for aquafeed.  As everyone involved with aquaculture knows, the sector continues to grow over time, and with that growth comes an ever-increasing need for feed.  Marine ingredients, especially fishmeal and fish oil are important components of aquafeed, and that position is not under threat.  Terrestrial crops such as soya and wheat which have been used as partial substitutions for protein and fat in feeds are not set to provide significant increases in production as there just isn’t the opportunity for additional arable farming in undeveloped regions of the terrestrial environment around the world.  What is required is a range of novel ingredients that complement the use of fishmeal and fish oil, which secure production efficiencies and health of farmed stock, maintain farmed fish quality, without carrying any additional significant environmental impacts within a global animal feed ingredients sector.  The farming of insects and the production of insect meal seems to fit in rather well with that viewpoint.

Some of the opinions expressed during the day exposed unfortunately misinformed positions on the environmental impacts of fishmeal and fish oil production.  Presumably this is a strategy for communicating the perceived benefits of insect farming as holding apparently superior environmental credentials in the minds of some.  There is a place for novel ingredients production, but let’s be clear – the vast majority of fishmeal and fish oil production is sustainable with at least 50% of annual production certified as coming from responsibly-managed fisheries.  In addition to this, insect meal production has a very long way to go to reach anything like the commercial volumes that the marine ingredients sector has been supplying for decades, and upon which the modern aquaculture industry is founded.  The novel ingredients need to stay more focused on their own stories and less on criticising others if they are to mature into commercially viable industries in their own right.

From a production perspective we heard a lot of detail about research and small-scale commercial production units.  The production of insects for feed seems to be focused on the Black Soldier Fly (BSF).  With BSF there is considerable available substrate that could be utilized for feed for farming BSF, and that in itself does make the system potentially useful in achieving a protein supply from low value resources.  When some of those resources are already themselves used as ingredients directly for aquafeed (e.g. DDGS, microalgae), then one does question whether the addition of another trophic level in the production process is worthwhile as it carries cost and environmental impact considerations.  One fascinating point was that the insects themselves produce faecal waste material (known as frass), which also carries some regulatory and practical disposal issues.

In terms of production quantities, the discussion indicated that there are really only pilot scale, or very small commercial volumes at the current time, although there was also some apparent confusion between quoted volumes of insects, and volumes of actual insect meal.  The reduction ratio from insects (i.e. pupae) to meal was quoted as roughly 4-5:1, which is similar to fishmeal, suggesting that any equivalency in global insect meal production will require an approximate 20 million tonnes of insects to be produced every year.  That is very far off current volumes.

From a nutritional perspective we heard that insect meal carries a similar amino acid profile to fishmeal.  This must be a standard, somehow scientifically-defined, fishmeal, because as those in the industry know, fishmeals differ in composition depending on the raw material, so the amino acid profile changes according to which fish species is present in the derived material.  That fact aside, it appears that there is a strong point of difference between fishmeal(s) and insect meal with regard to the other micronutrients present such as the vitamins and minerals that are present in rich concentrations in fishmeal and which the feed companies know so well are crucial for fish physiology and growth.  Not least in this regard is the presence of the long chain omega-3 fatty acids in fishmeal, and having seen a picture of the fat portion of insect meal at the workshop, which appeared to be solid at room temperature (i.e. highly saturated), there seems little quality comparison with regard to lipids.

Other nutritional issues include the presence of chitin and the need for its removal or management in the product as it has comparatively low digestibility with different fish species having apparently different chitinolytic enzyme profiles.

This was an interesting and useful information exchange platform in a room full of enthusiasm for a potential new industry and what that could mean for Scotland.  It can be important, but as with all aquafeed ingredients they should be complementary to marine sources, to ensure that the optimal nutritional benefit from fishmeals and fish oils can be achieved in support of high-quality aquaculture products.

Dr Neil Auchterlonie