What does a 40% protein diet actually mean?
Many feeds boast high protein values. On one hand, protein requirements for fish are well researched and dictate how feeds are produced. On the other hand, protein is valuable. Feed companies know high protein diets can command a higher price-tag. This environment has created an interesting, and quite complicated, situation.
In nature, many fish eat other fish. This leads many people to assume that more protein is simply better. However, too much protein can be detrimental in terms of water quality, as extra protein will pass through fish and into the environment. We try to balance our formulations with respect to protein and energy—supplying protein in levels that will support maximum gain (protein accumulation) and utilizing better forms of energy (fats) for energetic considerations. This balance is called protein to energy ratios.
We will save going into specific detail about ingredients for a later time. For now, let’s just explore what “40% protein” on a tag actually means and the different approaches to achieving it.
Diets are comprised of a number of components. Each component supplies a unique set of nutritional compositional details. Many ingredients by themselves are higher than 40% protein, especially animal-based protein sources like fish and animal meal. Each of these protein sources vary in nutritional make-up…and price. Creating a feed for fish is a complex and multifaceted task, and formulations vary in terms of the ultimate result. While many people immediately think they want a feed that produces the fastest growth, others may want to balance growth with environmental impacts (like phosphorus discharge). Others may take into consideration fish health and well-being. Focusing on one particular outcome often comes at the expense of another, hence the difficulty in providing high quality fish feeds for such a diverse marketplace.
There are multiple grades and qualities of protein sources which we will dive more into at a later time, and there are multitudes of protein sources than can be utilized for the formulation and production of fish feeds. In the table below we are providing a simple, abbreviated chart of some of the more common ingredient sources used in fish food production and an approximate idea of their compositions.
|Animal Protein Sources||% Protein||% Fat||% Ash||% Fiber|
|Fish Meals||50-80||8-15||10-25||> 1.0|
|Poultry Meals||49-64||10-25||11-25||> 1.3|
|Plant Protein Sources|
|Soy Products||38-75||1-20||1-50||3 – 30|
As many of you may notice, most of the ingredients have crude protein values higher than 40%. In order to achieve a final feed protein value lower than the individual protein source, the diet needs to be “diluted” down. If you have an ingredient with a high protein (ie. Fish meal), it needs to be mixed with something with a low protein (corn) in order to bring the average protein down. The higher the protein level of the specific ingredient, the more dilution is required. This presents a crucial decision to nutritionists: what protein source do you use and how do you fill out the rest of the formulation? These decisions will ultimately determine not only the cost of the feed, but also its performance with respect to fish growth and health, as well as its potential impacts on the environment.
To further complicate this, traditional floating fish feeds are extruded. Extrusion only works with starches and carbohydrates…which fish don’t generally eat. Fish and animal meals do not contain much starch content. Without starches the feed will fall apart and will not float. For example, a fish feed pellet comprised entirely of fish meal would overcook in an extruder and create an unstable and fast sinking pellet. Typically, plant products are utilized as starch sources. The long term effects of floating feeds high in starches and carbohydrates are poorly understood in fish and an area of active research and interest for us here at Optimal Fish Food.
Optimal Fish Food takes the approach of using high quality ingredients for not only the main protein source, but for ALL of the ingredients. Many of the conventional “dilution” type ingredients bring along sources of undesirable components. These are antinutritional factors like phytic acid and trypsin inhibitors, xanthophylls which can cause fillets to yellow, improperly balanced minerals which can facilitate disease, or low digestibility which can decrease water quality.
As indicated by the chart, there are a wide variety of protein sources and grades to choose from. We’ll talk more about how we choose from that list and how we go about evaluating our ingredient choices in our next installment.
Optimal Fish Food endeavors to provide transparent dialogue, innovative solutions, and performance-based fish feeds that promote fish health and longevity. Throughout our journey, we cannot express our gratitude to all of you who have supported us, continue to support us, and provide us with great feedback, comments, information and observations.
We receive a lot of questions every day, and we are delighted to share what we can. In an effort to address some of those questions more openly, we are going to start a series to share how we go about developing our fish feeds.
We are continuously updating our feed formulations based upon the very latest of research—both internal and external—so our feeds are always at the forefront of discovery. We feel that if our feeds are not changing, then they are stagnant, and therefore they are not advancing the latest in nutritional advancements. However, we do not “experiment” on our customers and their fish. Instead, we work internally to test our feeds and then release them to you AFTER we are confident that they will provide good results. In contrast to other feed manufacturers that may want their feeds to “never change”, our feeds will continue to evolve so as to incorporate the very latest proven advances in nutritional know-how and expertise. This is our commitment to our customers.
Starting today, we will begin a series of posts in which we will dive into some of the behind-the-scene details of how Optimal Fish Food is made. We will talk about things we are doing differently and discuss the many moving components required to produce fish feed ranging from ingredient selection, to extrusion technology, to feeding trials.
Join us as we dive into some deeper aspects of how Optimal Fish Food is reinventing fish food and why we stand so confidently behind our product.
What’s left to learn?
The short answer: A LOT.
There are many components that go into creating fish food. In very broad strokes making feeds requires understanding the true nutritional requirements of various fish, selecting feed ingredients, formulating them into diets, and manufacturing the pellets. Each of those broad categories carries a multitude of decisions and complexities. Throughout this series we will touch on a number of them, but a good place to start is a quick history lesson.
From their origins before the 1950’s when fish were usually fed raw protein like horsemeat, aquaculture feeds have progressed immensely over the past 50 years. However, even at the present time, the compositions of feeds for different fish in various countries varies widely. A strong focus on improvements in feeds for carnivorous fish like salmon and trout initially relied on very high inclusions level of fish meal—fish eat fish. However, beginning in the 1990’s there was increased focus on environmental sustainability, as well as the increased knowledge of actual requirements of specific nutrients (ie amino acids, fatty acids etc) that were accumulated via intensive governmental funding by aquaculture-focused countries (like Norway) as well as the US to support aquaculture programs at academic institutions to develop better formulated fish feeds. Such efforts have been enlarged and augmented by private companies based on a combination of commercial aquaculture experience and laboratory studies. In fact, there has been more knowledge discovered and tested about fish nutrition, gut biology and feed manufacturing techniques in the last five years than there have in the previous twenty. The pace of understanding and potential improvements in fish nutrition and feed developments is accelerating not slowing and certainly not stopped due to the fact that we know most of what there is to learn about these areas.
Our industry has now progressed to the point that aquafeeds are specifically formulated for particular species of fish, optimizing not only protein and fat levels, but also, specific amino acid requirements, specific fatty acid requirements, and specific levels of vitamins and minerals that are necessary for optimal growth and health of a wide variety of cultured fish species. Unfortunately, the “depth and breadth” of that knowledge differs depending on the market demand for specific fish species.
Many traditional fish food formulators employ a practice called “low-cost formulating” which is pretty much what it claims. Since many ingredients that go into fish feeds are commodities, their prices can be fairly dynamic. In order to ensure a set margin, companies are encouraged to change the ingredients to minimize the costs. Although the diet may stay a fixed percent protein, the ingredients mixed together to achieve it can be vastly different. We will expand upon this in our next post!