Protein is in high demand worldwide. As the demand increases alongside a growing middle class, meeting the demand will require greater availability of feed protein products for the meat animals we consume.
By Mallorie F. Wilken, PhD May 31, 2019
Traditionally, one cheap source of protein has been distillers grains used in feeding swine, poultry, and dairy and beef cattle. Research has also shown opportunities in feeding it to fish and other aquatic species. Distillers grain’s versatility has increased its global demand for feeding meat animals.
At the same time protein demand is growing, the ethanol industry is maturing and looking for ways to add multiple revenue streams. Diversification is necessary and crucial for plants to remain profitable in this seasoned market.
Figure 1. As the amount of meat humans consume increases, so does the demand for feed protein products. Source: FAO, 2018.
Concentrated protein distillers grains will be one of the feed products aiding plants in developing new income streams while continuing to provide feed for animals to fulfill global meat consumption. Because each meat animal species has differing nutritional requirements for optimal performance, formulations incorporate feed commodities in various proportions to meet those requirements. While corn has traditionally been the primary commodity to add energy to a diet for swine, poultry and cattle, soybean meal has often been the supplier of protein, because of the more appropriate amino acid profile to meet dietary needs of swine and poultry compared to corn.
More recently, distillers grains have been able to replace most of the protein supplement in cattle diets, but this corn protein isn’t as high in lysine content or as balanced in amino acids as soybean meal and thus cannot make a similar replacement in swine or poultry diets.
High protein distillers feed products are capable of supplying a larger amount of protein at a lower inclusion level compared to traditional distillers grains. However, it is still corn protein and the ratio of lysine to leucine remains 3:1, compared to 1:1 in soybean meal, which needs to be taken into account. High protein distillers grains have the potential to replace portions of soybean meal to make the diet more cost effective to the producer while maintaining performance. Further research is being conducted to help us better understand the optimal levels of inclusion of the feed product in each species.
It is important to note that, while valuable, protein is not the only component in distillers grains offering feeding advantages when added to animal diets. Fiber, fat and other intrinsic properties are additional factors. The bran or fiber portion of corn has roughly 20 percent protein content (dry matter basis). This protein is incredibly valuable in cattle diets as the microbial environment in the rumen is able to digest and utilize this fiber for energy and growth, unlike that of swine and poultry. Cattle producers will often note intake and health benefits of diets containing distillers grains compared to those without the product. Cattle will have more consistent consumption rates and, therefore, less digestive issues. The ability to separate the fiber and protein streams has the potential of directing the feed products to more species-specific commodities and increasing revenue for the plant itself. When high protein distillers grains and corn fiber, mixed with condensed distillers solubles such as ICM’s new feed, Fiber&Syrup (FS), are compared to traditional wet or dry distillers grains plus solubles (WDGS or DDGS) in beef cattle diets, animals observed statistically similar performance (see Table 1). Cattle consuming diets with ethanol feed products at 40 percent inclusion (dry matter basis) had similar to greater performance than those fed corn-only diets.
Since the ethanol feed products were fed at levels exceeding the required amount of protein, the cattle were able to utilize the feed as an energy source. This also illustrates that as long as protein requirements are met, cattle will “waste” the protein supplied by ethanol feed products as energy, as shown in Table 1 by the equivalent performance of cattle fed high protein distillers grains (37 percent crude protein) and FS (32 percent crude protein). If cattle are able to perform similarly with enough but less protein in the diet, we should feed FS in the feed yards and utilize the more concentrated, higher protein products in species like swine and poultry where protein is valuable and expensive.
Fish is a protein source with increasing demand globally for human consumption. This demand shift is providing opportunities for farming fish (Figure 1). High protein distillers grains have provided increased performance in tilapia when added to diets at either 15 percent or 25 percent inclusion (dry matter basis) as shown on Table 2. Tilapia fed ICM’s high protein distillers grains at 15 percent or 20 percent observed significantly increased weight yield (0.28 percent and 0.29 percent respectively) compared to those fed a traditional control diet of 0.26 percent. These results suggest an opportunity to feed more concentrated protein ethanol feed products.
As feed and animal production grows to meet protein demand, new requirements and U.S. Food and Drug Administration guidelines will require technology and innovation to address the need for consistency, providing new opportunities to boost an ethanol plant’s bottom line. Consistency and verification will drive customer loyalty to purchase the feed and the price at which they choose to buy, especially as distillers grains transition from an ethanol byproduct to a feed commodity in the minds of animal producers.
The optimal balance for ethanol plants today is met by improving the ethanol production system and increasing revenue through diversified feeds that meet the needs of the local and trade markets. Market conditions are forcing ethanol plants to reevaluate their current production methods toward plant flexibility. Plants must be able to create value in all facets of production, including ethanol, corn oil, and feed products. This requires plants to adopt process technologies that separate feed streams and allow the plant to recombine, concentrate, or process each feed to meet demands.