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Ruben Groot: Beneath the surface: Producing quality fish feed with sustainable resources

November 27, 2018

Aquaculture is on the rise, but with a limited supply of fish meal and fish oil, sustainable alternatives are needed. 

The following is an edited transcript of Tom Martin's interview with Ruben Groot. Click below to hear the full audio:




Tom:              We're talking with Ruben Groot, aquafeed nutritionist at Alltech Coppens, where he not only oversees feed quality but also engages in research and development at the Alltech Coppens Aqua Centre. Thank you for being with us, Ruben.


Ruben:           Thank you, Tom.


Tom:              As the aquafeed nutritionist at Alltech Coppens, you are responsible for maintaining the quality of almost 200 different feed recipes. Is that variety species-specific, and can you tell us about the work?


Ruben:           Indeed, we have a very high number of recipes. They’re not only species-specific, they’re also system-specific. We produce for roughly ten different fish species. The most dominant are trout, sturgeon, catfish and some other species, such as sea bass and sea bream.


                        So, we have feeds for different species, but we also have feeds for different systems. Trout, as an example, are grown in recirculating aquaculture systems (RAS). And, for all these different systems, we also have different feeds.


                        In addition to industrial feeds, we have quite a large range of hobby feeds — for angling, for hobby, for ponds, for aquaria. It's a high variety of products that we have.


Tom:              To stay on top of quality and maintenance, do you have to constantly sample and test?


Ruben:           That's very important for maintaining the high quality that we require for the feeds. We actually test quality at all the different points in our factory. When the newer raw materials are coming in, they will first be tested. We’re looking at physical properties — does it look good? Is the smell okay? We even have a new infrared device, which allows us to measure protein, fat, ash and phosphorus within seconds. That really helps with maintaining the quality.


                        We also test further down the line. Raw material is the first point, and then, of course, also, the quality control of the end products is very important. So, we look at physical parameters — again, is the quality of the pellet okay? Is it hard enough? Is the shape all right? Is it too big or too small? And, again, we look at the protein and fat levels, among others. There is a lot of quality control going on in the factory.


Tom:              For those not engaged in aquaculture, could you explain why fish meal and fish oil are not an endless resource?


Ruben:           Fish meal and fish oil are generated from wild-caught fish. The supply of fish meal and fish oil cannot increase any more, but aquaculture is increasing very fast. There is a limited supply of marine resources. We now need some substitution of fish meal and fish oil.


Tom:              Is it possible to produce a high-quality product without those ingredients?


Ruben:           Definitely, yes. For the last eight years, we have been developing Neo Green trout feed, which is a completely fish meal- and fish oil-free diet for trout. Trout is a carnivorous fish species. This is a very difficult fish to create a fish meal- and fish oil-free diet for, but we have been able to successfully replace the fish meal and the fish oil while maintaining a high-performance feed.  


Tom:              I mentioned before that you are the aquafeed nutritionist at Alltech Coppens. Can you tell us a bit more about that role and what you do at Alltech Coppens?


Ruben:           My main responsibilities are, of course, maintaining the quality of the feed formulation itself. I also work intensively with different departments in our company. For example, with the purchasing of raw materials, I need to be aware what kinds of changes are happening in the market, so I can adjust the formulations based on that. Of course, the bases of the price are the recipes, but you can imagine that fish feed production is also very dependent on the formulation that's used. There is a lot of communication between nutrition and production so we can ensure high-quality of the feeds in the entire process.


Tom:              Can you talk about the research that's going on at the Alltech Coppens Aqua Centre? Is there a proprietary issue there, or are there things that you can talk about?


Ruben:           As a nutritionist, I'm also part of the research and development (R&D) group at Alltech Coppens. It illustrates the strong link we have between research and nutrition. Almost everything that we do in R&D can be directly translated into the feed formulation. Some examples of that are testing of new raw materials we can use into feeds formulation, and researching the effect additives, for example.


Tom:              What are some new ideas in feed development that are helping aquafarmers convert to a zero-fish-in and zero-fish-out process?


Ruben:           The main development is looking beyond replacing fish meal by plant protein sources. In our case, we use some animal byproducts to replace the fish meal. But some new developments are, for example, insect meal, which is a very promising new animal protein source. I have also had a lot of contact with a producer that is working on bacterial protein. It is also quite an interesting new raw material that could be used to replace fish meal.


Tom:              Is there an insect or are there insects that show particular promise?


Ruben:           At the moment, there is a lot of work going on in black soldier fly larvae. They mainly use the larvae because the larvae do not have an exoskeleton yet. The protein content in that is still very low, and fish have some difficulties utilizing the protein. The black soldier fly larvae are, however, one of the more interesting species.


Tom:              When you're developing feeds, do environmental impact considerations come into play?


Ruben:           Yes, of course. If I just take one example, of phosphorus: phosphorus is a mineral that is required for the normal growth of fish, but [if] phosphorus levels are too high, the fish will not be able to utilize it to the full extent. Some of that excess will go back into the environment. It's about finding a balance. A little is not good, but too much is also not good.


Tom:              Alltech Coppens is known for its ability to develop feeds for eels, which I understand is quite challenging. What makes the formulation or production of eel feeds more difficult, and how has Alltech Coppens overcome that?


Ruben:           The eel is a very picky eater; it will react to the smallest changes in quality. So, for example, we have made contracts with one fish meal supplier to always give us a constant batch of fish meal for those feeds. From the raw material side, we know we always have a constant supply of raw materials.


                        In addition to that, we also focus on maintaining the quality of the pellets that we're using. When we make eel feeds, we make high volumes. Then, we can make one batch that has the same quality — that helps us a lot.


Tom:              What recent innovations in aquaculture have captured your imagination and your interest?


Ruben:           Regarding raw materials, for example, the bacterial protein is, I think, very interesting, but I already talked a little bit about that. Another thing that has really caught my interest is net energy formulation. This is still a fairly new concept in aquaculture. It has been around for a lot of years in pig and poultry nutrition, but it shows a lot of promise in aquaculture as well.


Tom:              Ruben, what do you enjoy most about what you do?


Ruben:           The thing I enjoy in aquaculture is that there is still so much to do. There is still so much to discover, so much to improve. There are so many different fish species you can work on. It's really the difference in the work — no one week is the same. It's always different. It's —


Tom:              Never a dull moment.


Ruben:           Never a dull moment.


Tom:              Ruben Groot, aquafeed nutritionist at Alltech Coppens. Thank you so much for being with us.


Ruben:           Thank you as well, Tom.



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