Do Enzymes Add Value? ExPress® Soymeal in Swine Diets
Diet quality plays a critical role in swine growth, performance, and overall production efficiency. For nutritionists, selecting high-quality ingredients with superior digestibility is key. One ingredient that continues to demonstrate strong value is ExPress® soymeal.
Soybeans are widely used in swine diets, but they naturally contain antinutritional factors (ANFs) such as trypsin inhibitors, which can reduce amino acid digestibility and limit animal performance. Proper processing is essential to deactivate these compounds and unlock the full nutritional potential of soy.
ExPress® soymeal is produced using high-shear dry extrusion, where friction serves as the primary heat source, followed by mechanical pressing to partially remove the oil. This process results in a product with 6–8% residual oil, contributing additional dietary energy and making it a unique ingredient compared to conventional soybean meal.
The benefits of ExPress® soymeal stem from how processing alters the soybean. High-shear extrusion ruptures cell walls, improving nutrient accessibility, while effectively reducing ANFs such as trypsin inhibitors. At the same time, the process minimizes Maillard reactions, preserving amino acid quality. These combined effects lead to greater digestibility of amino acids and energy than solvent-extracted soybean meal.
From a formulation standpoint, ExPress® soymeal offers practical advantages. Its high nutritional value can simplify diets, reducing the need for added fats, oils, and even crystalline amino acids.
A key question, however, is whether enzyme supplementation can further improve its digestibility. To address this, a study evaluated a complex enzyme mixture (CEM) containing carbohydrases and protease in diets with 44% ExPress® soymeal, fed to growing pigs (initial body weight ~30 kg). Two-ingredient batches were tested.
The results were clear: the enzyme mixture did not improve the digestibility of energy, most amino acids, or other nutrients. Notably, lysine digestibility was already high at 90.6%, and was not enhanced by enzyme inclusion. Since lysine is typically the first limiting amino acid in swine diets, this result highlights the inherent quality of the ingredient.
These findings reinforce that the processing method is the main driver of nutritional value. The combination of efficient ANF deactivation and extensive cell wall disruption allows for optimal nutrient absorption without the need for additional enzymatic support.
Final Takeaway
ExPress® soymeal stands out as a high-value ingredient for swine feeding. Its superior digestibility, energy contribution, and consistent performance allow nutritionists to formulate simpler and more cost-effective diets. Importantly, the lack of response to enzyme supplementation confirms that its nutritional benefits are already maximized through processing, making it a reliable and efficient protein source in modern swine nutrition.
