Separation for Oil, Fractionation for Protein, So What about the Fiber?

As the industry evolves, those willing to face the challenge of finding a market for fiber-rich products in order to produce more high-protein feed will reap the most benefits. ICM's Solbran is poised to be a competitive source of digestible fiber.
By Mallorie F. Wilken | October 07, 2021

Protein, protein, protein …

Distillers grains and protein are a major focus for feeding the world’s growing population and middle class  through animal agriculture. The focus is for good reason—in recent years, distillers grains have proven to be an animal feed commodity with its own supply and demand curves that are no longer tethered to corn like they used to be.

The cattle industry is the original user of distillers grains. The producers, feeders and nutritionists learned how to feed this ethanol coproduct before universities even had funding for the research. The leaders in the cattle industry used lab-reported product composition to determine the first inclusion levels in commercial settings. They experienced firsthand the benefits and challenges offered by feeding distillers grains. The differences in animal performance observed from feeding wet product (35% solids) versus modified product (45% solids) versus dried product (90% solids) initiated questions for the preliminary research trials. When the trademarked Base Tricanter System (BTS) was available for installation to pull distillers corn oil (DCO) from the feeds, the cattle feeders discovered that the reduced fat content caused feed efficiency to decline slightly. This shift in product composition had a negative impact on their bottom line due to cattle staying on feed longer and a need to increase the inclusion levels of more expensive feeds in the diet to maintain growth and performance. Cattle feeders today often purchase DCO to obtain growth rates similar to those observed in animals prior to BTS. These actions display the importance of distillers grains and their components as a major feed ingredient in meat animal rations.

Fat found its way to the market very easily via the demand for corn oil in the feed and diesel markets. Protein is in high demand globally for livestock production. However, corn remains an imperfect protein in some animal diets because it doesn’t contain enough of the amino acid lysine in relation to the other essential amino acids like leucine. Oversupplying some amino acids can be just as damaging to the animal as undersupplying their first-limiting demands. For instance, swine are limited by the amino acid lysine. Poultry are limited by methionine, followed by lysine. Cattle are more complicated because their supply of ruminal bacterial protein offers some 60% of the animals’ requirements. From a diet concentration standpoint, aquaculture require the highest amount of protein at 50% of their dietary needs, followed by cats (40%), dogs (40%), broiler chickens (20%), dairy cows (17%), hogs (16%), laying hens (16%), sows (14%), feedlot cattle (13%), and beef cows (8%), all on a dry matter basis (source: National Resource Council reports).

These protein requirement variations certainly prove the need for continued education and research to maximize diversified distillers feed products. Protein separation offers ethanol plants opportunities for expanding into new feed and food sectors, meeting demands at more feeder-friendly prices compared to traditional protein sources, and even helping the ethanol industry mature through innovation. Still, when it comes to delivering full feeding value, distillers grains are more than protein and fat.

Understanding Fiber

Traditional, unfractionated distillers grains products have been highly demanded as an inexpensive protein additive in livestock diets, with the energy from the included fiber and fat as secondary benefits. Through fractionation, the fiber component is washed clean in a counter-current process via ICM’s trademarked FST/FST Next Gen, which allows the soluble portions to remain in the process and continue to the fermenters, while the fiber bypasses the plant as a whole and does not experience the ethanol production process. The unadulterated fiber from front-end separation is cleaner and offers a larger particle size. A portion of the syrup can be added back to the fiber to create a product ICM calls Solbran. While corn fiber is not an effective source for supplying the “scratch factor,” like alfalfa or corn stalks that scratch the rumen wall to maintain gut health, it is still a readily fermentable source for energy in the rumen.

As illustrated in Table 1, Solbran is highly competitive against other digestible fiber sources in the feed industry. The largest advantage of Solbran is the additional digestibility over other ethanol coproducts from the wet milling industry, such as wet corn gluten feed.

Understanding the digestive process in cattle rumen explains the good digestibility of Solbran. The cattle rumen contains specific Fibrobacter and Ruminococcus bacteria, which prefer to consume and break down fiber structures over other carbohydrate sources. These types of bacteria are not used in the ethanol production. Only Saccharomyces cerevisiae is used; it digests the starch components in corn. For this reason, the fiber is neither helped nor damaged by going through the ethanol fermentation process. Therefore, the front-end fiber separation with ICM technologies allows Solbran to remain intact and ready for consumption by cattle, where it is best digested and utilized in protein production for human consumption while providing operational benefits to the plant.

As the industry continues to mature and consolidate, those willing to face the challenge of finding a market for fiber-rich products in order to produce more high-protein feed will reap the most benefits. Research done by feeding distillers grains to cattle has proven the feeding value of protein, fat and fiber. This research has shown more than just improvements in feed efficiency by maintaining a healthier ruminal population in the gut. Healthier animals remain more consistent in intake, gain, growth and production as a whole. Research also repeatedly proves that the cattle rumen is able to maintain a lower, more consistent pH allowing for improved feed efficiency and overall gut health. The diet is easier to feed, and the animals are more productive even when distillers grains are fed at levels less than 10% of the diet. As a combination of the fractionated fiber and syrup, Solbran meets and exceeds these expectations.

In a recent study conducted on feeding yearling steers during the winter of 2020 at South Dakota State University (Table 2), Solbran-fed animals were able to match the performance of control-fed cattle at 20% replacement for corn in finishing diets. This means that Solbran was able to maintain performance, even without the other 10-12% of protein contained in distillers grains. The extra 10-12% of protein is the 3-4 pounds of protein fractionated with the new ICM technologies, which allow the plant to sell a protein-driven, yeast-enriched product that will bring a premium price compared to traditional DDGS. The installations of feed separating and concentrating technologies transform ethanol plants into biorefineries. Ultimately, biorefineries can produce feed products that have greater feeding value and more advantageous component combinations for different animal species, creating more revenue opportunities.

As the price of feed increases, cattle producers will try to identify cheaper sources of protein. They will try to keep a portion of distillers grains in the diet because of the intrinsic values offered in improved gut health, consistent bunk management and intake, and increased rate of growth. Solbran maintains all the benefits of feeding distillers grains and is the solution to the fiber concern whether sold wet, dry or pelleted. Solbran will certainly be able to meet the feed demand of cattle producers. Yes, it will be a change. Change can be challenging. However, this change represents the advancement of feed products into the marketplace to meet each species’ specific nutritional demand.

Distillers grains fractionation is available, and the options of feeding the protein portion are endless and often determined by feed composition and price. In addition to protein, ICM has developed a beneficial solution for the fiber. Overall, we are reaching our goal of supplying protein to the world population while providing an additional product to plants for generating more revenue.

Author: Mallorie F. Wilken, PhD PAS

Technical Service Nutritionist
[email protected]