"Soybean Meal" is produced by solvent extraction of the oil, typically in large scale plants (500 to 5,000+ MTD) that operate 24/7 so the processing conditions tend to be very stable. In the last stages of the extraction process the meal is desolventized and toasted to insure all of the hexane (solvent used to remove the oil) is recovered using both direct and indirect steam heating. The result is that the process conditions of temperature and moisture are very well controlled and take place over a relatively long period of time, 20 to 40 minutes, and a relatively low temperatures resulting in a very consistent finished product. Certainly in some locations the meal can be "over toasted" making the protein less bioavailable, or "under toasted" and the enzyme deactivation inadequate, but all in all the products from a solvent extraction process are very consistent over time. The residual oil in solvent extracted meal is generally between 0.5 and 1%.
Most full fat soybean processes use a short time, high temperature process such as extrusion and expansion or the use of grain roasting equipment. As a result, the process is more difficult to control precisely and as a result some products may be over or under "cooked" which will impact both the nutrient availability, and the levels of the anti-nutritional enzymes that naturally occur in soybeans. This is further complicated by the fact that the processes do not run continuously and are subject to varying conditions during each start up and shut down sequence. As a result, "full fat soya" products tend to be more variable in terms of protein availability and anti-nutritional enzyme activity. The oil content in full fat soya products will typically range from 18 to 20%.
To complicate the issue even further, there are mechanical methods to extract soybean oil (screw presses) that normally work at high temperature and pressure to achieve the highest oil extraction, but do tend to "overcook" the proteins to the point they are only really useful as bypass protein in ruminant diets. The residual oil in the mechanical extracted meal is generally around 8-10%.
Due to the wide variety of processing methods, quality control tests that correlate well for one process (urease activity, KOH solubility) will not necessarily apply to alternative processes.
Dr. Albin and Dr. Wiseman, yes indeed I also agree with your comments because the video presented is actually a clip of a longer video and it is not fully representative of all of what I have to say reference full-fat soybeans. But both of you, Gentlemen, are authorities on the subject, have lots of experience and knowledge on the nutritional value of full-fat soybeans, so you can also further discuss the issues. I have watched and listened to Dr. Albin in some of his videos. Just for the record and the audience in Engormix, I have recently discussed the differentiation of quality control procedures when applied to soybean meal, and when the same procedures are applied to full-fat soybeans thinking that what applies to soybean meal applies directly and automatically to full-fat soybeans. And precisely one of the points that I have emphasized in this discussion is that soybean meal and full-fat soybeans are TWO DIFFERENT ingredients that emerge from two very different processes. While the predominant process for soybean meal production worldwide, as we all know, is the solvent-extraction process, for full-fat soybeans the processes are quite diverse. There are as many qualities of full-fat soybeans as processes exist, each one with its own conditions, advantages and limitations. To the best of my knowledge the term "FULL-FAT SOYBEANS" is a generic term for the product of processing RAW SOYBEANS (which ARE NOT full-fat soybeans as an INGREDIENT, with the possible exception of ruminants) to generate the animal feed ingredient, full-fat soybeans. In our experience there is not a correlation between urease activity and trypsin inhibitors ACROSS processing methods of full-fat soybeans, and consequently urease activity cannot be used as a guideline to indirectly estimate trypsin inhibitors. In contrast, also in our experience, solvent-extracted soybean meal ACROSS processing plants shows a fairly good correlation between urease activity and trypsin inhibitors. In a recent comment in Engormix I discussed in detail the scientific literature supporting the correlation in soybean meal. A similar discussion can be done to demonstrate that the solubility of the protein in potassium hydroxide is not correlated to digestible amino acid coefficients as it is in soybean meal. Consequently, KOH protein solubility does not apply to full-fat soybeans ACROSS commercial processing methods. So, what in our experience is the quality control test to determine if a lot of full-fat soybeans is adequate for monogastric nutrition? TRYPSIN INHIBITORS. This assertion does not preclude that another in vitro test, easier to run and also less expensive may be correlated with trypsin inhibitors. There are basis to believe that the protein dispersibility index (PDI) as utilized by dairy nutritionists [Hsu, J.T., and L.D. Satter, 1995. Procedures for measuring the quality of heat-treated soybeans. J. Dairy Sci. 78:1353-1361] may represent such an opportunity. We have no data for monogastric nutrition, yet. NELSON RUIZ NUTRITION, LLC; nelsonruiz@nelsonruiznutrition.com; Suwanee, GA USA.
Thanks for your information. I would like to see what is the kinds of soy that give a good durability in formulating turkey fattening.
We have to accept within a narrow view that Soybean meal refers to solvent extracted meal, and full fat soya for extruded expanded soya bean with the entire oil intact.
I have come to realise that in the industry we cannot but recognise 3 types of Soymeal that are produced commonly. The first is solvent extracted meal. The second is full fat soymeal. The third is crushed soycake usually produced by mechanical press. In the mash form, the term meal applies.
When properly processed for monogastric nutrition, they present different nutrient analyses. The oil levels are prominent. While soymeal can showcase 0.5 to 1.5% oil, soycake has 6 to 8%, and full fat 18 to 20%. Variations can occur as a result of levels of machinery efficiency.
It is necessary to accord recognition to these 3 products. We must carry the soycake along, while educating livestock and oilseed industry players on the differences between the products.
Dr. Anyanwu D.I.D. is a Veterinary practitioner, Animal Nutritionist, and Soya bean Processor.