Understanding Feed Mill Formulas

by | Oct 26, 2020

Every feed mill must create a series of formulas or recipes for their products, using a series of mathematical equations. This ensures the recipe can be replicated consistently. It also allows the mill to scale these recipes as needed without altering the nutritional value or mixing accuracy.

Why Technology Isn’t Enough

Today’s feed mills often rely on technology when creating the original formula or recipe, but this can lead to problems down the line. No machine is infallible, even if it works 99% of the time. If workers do not know how to formulate these equations by hand, the machine could produce a recipe that’s unfeasible due to cost, resources, and the complexity of the resulting feed.

This is no more apparent than when trying to reduce the overall cost of the recipe. Feed mills will often use algorithms to reduce their expenses by entering additional data into the equation based on the cost of materials. However, this process can easily get out of control as the machine continues to add ingredients and layers of equations on top of the established recipe.

Learning the Basics of Feed Mill Formulas

Feed mill employees should learn how to formulate these equations by hand, so they can double-check the work of the computer or complete this process by hand if the machine were to malfunction. Otherwise, workers will only learn using these programs and algorithms, limiting their knowledge of the production process.

When creating a formula by hand, start with the two main ingredients, usually corn and soybean meal. Depending on the feed particle size, we know that these ingredients will likely make up the bulk of the mixture, so let’s assume they represent 95% of the finished product.

Thus, A (corn) + B (soybean meal) = 95.

Based on the protein contents of these ingredients, we know that corn comes with an 8.8% protein rate and soybean meal comes with a 44% protein rate. If we want to create a feed with 18 grams of protein per serving, we end up with the following equation:
8.8(A) + 44(B) = 18

We can then use algebra to come up with an exact ratio for the corn-soybean meal. Once we do the math, we’re left with approximately 67.5% corn and 27.5% soybean meal.

We can then do the same thing for the overall calorie count of the feed. This shows us how much soybean oil we will need to add to arrive at the proper energy levels. Apply the calories or energy per kg for each ingredient based on the overall goal. Corn comes with 3,300 Kcal/kg, while soybean meal comes with 2,430 Kcal/kg. Let’s use 3,000 calories as an example. If we use “C” for soybean oil, which comes with 9,200 Kcal/kg, this leaves us with:

3300(A) + 2430(B) + 9200(C) = 3000

Algebra then leaves us with 1.2% soybean oil. Use the same approach when adding other ingredients, such as phosphorus, salt, and calcium based on your preferred nutritional value.

If the resulting mixture is over or under 100%, just add more of your two main ingredients or assume that they make up more of the finished formula, such as 97% instead of 95%.

This is an easy way to formulate equations by hand in addition to using a computer. Additional refinement can make the math more complicated, especially when trying to lower the price of each batch of feed. That’s why many teams use computers, but it’s still helpful to master this rudimentary approach to feed mill mixing.

These formulas will also affect the overall layout of your facility. Contact the Salt Lake City Construction professionals at Halverson Company to learn more about the feed mill construction process.