Understanding Bypass Protein Soybean Meal in Dairy Nutrition
With bypass-protein soybean meal being such a common ingredient in today’s dairy rations, producers and nutritionists alike sometimes lose track of what they are actually feeding. At times, it is easy to simply look at the various meals as a commodity that shows up to the feed mill or farm with similar names and attributes, and forget they are indeed different products, produced using different procedures, by mills with potentially very different quality control protocols.
Nutritionist tweak and manipulate diets in an attempt to bring an exact balance of nutrients to their customers’ cows, but then often give feed mills the green light to use whichever bypass soy product the mill currently has on hand. Assuming these products are the same (or close enough) inadvertently allows great variation to come into the diets they have carefully balanced.
Mechanical vs. Solvent Extraction: Key Differences in Soybean Meal Processing
How Bypass Protein Soybean Meal Is Produced
Let’s start with the basics. Bypass-protein SBM products tend to fall into two distinct categories depending on production methods: either mechanical extraction or solvent extraction. This is referring to the process used to de-fat the soybean and gives rise to the first major difference in the final product; the fat content. Both protocols start out roughly the same. Soybeans are cleaned, cracked, exposed to heat, then flaked, extruded, or ground.
Solvent-Extracted Soybean Meal and Its Risks
With solvent extraction, the crushed beans are washed in hexane to remove the oil. Increased environmental and manufacturer risk is present with this process compared to a mechanical process. Solvent-extracted products may also be de-hulled. Crude fiber and protein percentages will vary from product to product depending on the percentage of hulls remaining in the product.
Expeller (Mechanically Extracted) Soybean Meal Benefits
The mechanical extraction process is a chemical-free process. Extruded beans are pressed and the meal is separated from the oil. A chemical-free process also means less inherent environmental and personnel risk during manufacturing. ExcellerPro is produced using the mechanical extraction process.
Protein and Fat Variability in Soybean Meal
Typical Nutrient Ranges: Mechanical vs. Solvent Soybean Meal
Typically speaking, meal produced from mechanical extraction results in a product that has approximately 45-47% protein and 7-9% fat. Solvent-extracted SMB on the other hand can range from 47-51% protein (depending on if it’s de-hulled or not) and from 1-2% fat.
However, across different manufacturing systems, some variation between products can occur depending on processing methods and quality control practices. In reviewing samples from multiple SBM suppliers, one product on the marketplace showed a broader range in nutrient levels, with protein from 40.5–43.9% and fat from 11.4–15.4%. This illustrates how differences between products can impact ration consistency. If a ration is designed around a specific nutrient profile a substitution may lead to unintended variation in what is ultimately fed.
How Processing Methods Affect Rumen Undegradable Protein (RUP)
Heat Treatment, Roasting, and Digestibility Differences
In addition to differences in fat extraction, there are also differences in heat-treatment protocols with regards to types of roasters, steeping procedures and times, cooling of product, etc. These products could then vary greatly in RUP and intestinally digestible protein.
Why Quality Control and Consistency Matter in Feed Ingredients
It’s important to point out that there is not one correct way of producing bypass-protein SBM, but the results of each process do produce vastly different final products. Likewise, quality control needs to be a priority of the manufacturer.
Consistent, High-Quality Soybean Meal from Quality Roasting
At Quality Roasting, we work hard to minimize nutrient variation with the goal of providing a consistent, high quality, predictable product. We know the importance of providing the cow with the product you actually planned on feeding her. If you have product or quality questions, feel free to reach out.
Office Phone# 920-775-9279