In a recent special study, the Food and Agriculture Organization of the United Nations noted, "…the amount of fish that can be produced annually from the wild is finite. Thus, much research has focused on finding replacements for fishmeal and fish oil in fish feeds."[1]

Verlasso uses yeast as a replacement for fish oil in feed. In doing so, we are able to reduce our dependence on feeder fish without compromising the health—or quality—of the fish we raise.

In the ocean, algae produce omega-3s. These omega-3s move through the food chain and, eventually, into feeder fish that provide the fish oil used in salmon diets.

We have taken the omega-3-producing capability of the algae and transferred it to yeast. This process is a genetic modification and we call the yeast a genetically modified microbe.  The result is that our yeast make omega-3s exactly as the algae do. 

We grow the yeast in a process called fermentation. As they grow, the yeast cells are fed a simple sugar (glucose) and salts. The yeast convert these ingredients into omega-3 oils and proteins.  We then make our  salmon’s diet with the yeast (which is less than 10% of the feed) and other ingredients such as proteins, oils and vitamins. With this menu, we ensure that the salmon continue to receive the omega-3 oils that are crucial for them and good for us.  At the same time, we dramatically reduce our dependence on challenged populations of wild caught feeder fish.

The use of yeast as an ingredient is a very old practice. Both beer brewing and winemaking rely on this simple organism as a catalyst of the fermentation process. In baking, yeast is the leavening agent that makes dough rise.

We developed our new feed recipe not to minimize costs but to reduce pressure on the ocean’s feeder fish. In addition, by feeding our fish a fish oil replacement, we can significantly reduce the level of PCBs (polychlorinated biphenyls) associated with salmon fed a 100% wild-caught feeder-fish diet.

Feed Efficiency

We measure the effectiveness of our salmon’s diet using an industry-standard feed conversion ratio, or FCR. This is one way to determine how efficiently the fish convert what they eat into body mass. Generally, the lower the FCR, the more efficient the feed.

Salmon are very efficient at converting feed. It’s possible to raise about five times more salmon on one pound of feed compared to beef cattle fed the same pound. Likewise, you can get about two and a half times more salmon than pork from a pound of feed. These numbers can vary based on location, agricultural conditions, season, weather and many other factors. But you can be assured that Verlasso salmon are a highly efficient use of natural resources.

Our innovative diet is one of the ways we’re able to feed our fish exactly what they need, and no more. We also use underwater cameras to monitor the feed, so it doesn’t pass through the pens uneaten. This is part of our conscientious approach to ensuring our fish’s health while minimizing environmental impact.

Fish Meal and Fish Oil

Verlasso is unique in its Forage Fish Dependency Ratio (FFDR) for fish oil. The fact that we have a 1:1 ratio for fish oil in particular, without compromising omega-3 content, is unprecedented and represents a fundamental change in salmon aquaculture.

Additional information about our feed from our blog:

Advancing a Healthy Dialogue on Sustainable Salmon Aqualculture

Our Revolutionary Approach to Feeding Farmed Salmon


  1. The State of World Fisheries and Aquaculture 2008, Part 3: Highlights of Special Studies.