Slide 1 Hi. My name is Dr. Sarah Cervantes-Pahm, and I would like to present this research in behalf of Kurtis Goebel, who has already obtained his Master's degree and has moved on to his promising career. His research is entitled, "Ileal amino acid digestibility in conventional and low-Kunitz soybeans fed to weanling pigs." And this research is already published at the Asian-Australasian Journal of Animal Science, volume 24, pages 88-95. Slide 2 Kunitz trypsin inhibitor is one of the two trypsin inhibitors that is present in soybeans. Trypsin inhibitors bind the enzymes trypsin and chymotrypsin, thereby reducing the activity of these enzymes in the small intestines. The reduced activity of trypsin and chymotrypsin in the gut results to low digestibility of protein and amino acids. Slide 3 Soybeans are usually processed with heat to denature the trypsin inhibitor or inhibitors and reduce its concentration in soybeans. But careful heating is important because excess heat could induce the Maillard reaction, that could also reduce the digestibility of amino acids, especially lysine digestibility. Slide 4 Low-Kunitz soybeans are new varieties of soybeans that are specifically bred to contain low concentration of the Kunitz trypsin inhibitor. Slide 5 Therefore, we hypothesized that low-Kunitz full fat soybeans would have greater digestibility of amino acids than conventional full fat soybeans. And we also hypothesized that heat treatment is not necessary to maximize amino acid digestibility in low-Kunitz soybeans. Slide 6 We did a 2x2 factorial experiment, and we obtained two sets of full fat soybeans. One set of soybeans were processed under low temperature, and this is at 21 degrees centigrade. And another set of soybeans were processed at high temperature, between 143 to 154 degrees centigrade. Therefore, we have a total of four treatments. The first two treatments were the low-Kunitz full fat soybean and conventional full fat soybean processed under low temperature, and the next two treatments were the low-Kunitz full fat soybeans and conventional full fat soybeans processed in high temperature. Slide 7 Let's look at the chemical composition of the full fat soybeans that were used in this experiment. If we look at the dry matter of the full fat soybean that was processed under the low temperature, the dry matter of these beans were between 88 to 90%, which were not quite different from that of the dry matter in soybean meal at 87.5%. However, when we heat treated the soybean meal, the dry matter increased to about 94 to 95%. If we look at the concentration of fat in these soybean products, the concentration of fat in the full fat soybeans were between 19.9 to 21.2%, and all were greater than the 1.48% in soybean meal. Fiber in soybean meal was at 3.5%, and the fiber concentration in the full fat soybeans were a little bit higher, between 3.8 to 4.5%. If we look at the concentration of trypsin inhibitors, we will see that the concentration of trypsin inhibitor in the conventional full fat soybean that was processed under low temperature was 35.4 TIU/mg. The concentration of trypsin inhibitor in the low-Kunitz full fat soybean that was processed under low temperature was only at 23.5 TIU/mg, which indicates effect of variety on the concentration of trypsin inhibitor in these soybean products. If we look at the trypsin inhibitor concentration in the soybeans that were processed under high temperature, both the conventional full fat soybean and the low-Kunitz full fat soybean has a trypsin inhibitor of 4 or 4.4 TIU/mg. And this is substantially lower than the trypsin inhibitor concentration in the full fat soybeans that was processed under low temperature. This shows the effect of heating on the trypsin inhibitor concentration in the soybean products. Slide 8 This slide shows the concentration of crude protein and some amino acids in full fat soybeans. And this is on an as-fed basis. We could see that the concentration of protein in soybean meal is at 47.5%, and was greater than the concentration of protein in all the other full fat soybeans whether they were processed under low or high temperature. The concentration of lysine, methionine, threonine, and tryptophan in soybean meal and the full fat soybeans were fairly similar with each other. Slide 9 This slide shows the standardized ileal digestibility of lysine. In the orange bar is soybean meal, in the blue bar is the conventional full fat soybean that was processed under low temperature, in the yellow bar is the low-Kunitz full fat soybean that was processed under low temperature, in the green bar was the conventional full fat soybean that was processed under high temperature, and in the purple bar is the low-Kunitz full fat soybean that was processed under high temperature. And we could see that the lysine digestibility in soybean meal is at 90.6%, and that the lysine digestibility of the conventional full fat soybean and the low-Kunitz full fat soybean that was processed under low temperature were lower that that of soybean meal. Comparing the lysine digestibility of the soybeans that were processed under low temperature, we could see that the lysine digestibility in the low-Kunitz full fat soybean was greater than the lysine digestibility in the conventional full fat soybean. However, when we heat treated these soybeans, we could see that lysine digestibility in these full fat soybeans, regardless of whether they are conventional or low-Kunitz, has a digestibility between 90 to 92% and were not different from soybean meal. Slide 10 This slide shows the standardized ileal digestibility of methionine. And again, we see the same pattern wherein the methionine digestibility in soybean meal is at 94%, and methionine digestibility in the soybeans that were processed under low temperature were lower than that of soybean meal. If we compare the methionine digestibility of the low-Kunitz full fat soybean and the conventional full fat soybean, methionine digestibility in the low-Kunitz full fat soybean was greater than that of the conventional full fat soybean. However, if we heat treated these beans, we saw an improvement in the methionine digestibility of these beans to 90 to 93%, which is now not different from the methionine digestibility of soybean meal. Slide 11 Again, if we look at the standardized ileal digestibility of threonine, we see a similar pattern, wherein the threonine digestibility of low-Kunitz full fat soybean was more than the threonine digestibility of the conventional full fat soybean when these beans were processed under low temperature. However, if we heat treat these soybeans, then we improved threonine digestibility to 86 to 88%, and these digestibility values were not different from soybean meal, which was at 88.3%. Slide 12 Looking at the effect of heat treatment, where we average the effect of heat treatment regardless of variety of soybean used. We could see that the soybeans, whether low-Kunitz or conventional full fat soybean, that was processed under low temperature has a lower digestibility of indispensable amino acids at 64.4% compared to the digestibility of animo acids in the soybeans that were processed under high temperature at 91.5%. This value is not different from the digestibility of indispensable amino acids in the soybean meal, which was at 92.3%. Slide 13 Looking at the effect of soybean variety. We could see that the digestibility of the mean of the indispensable amino acids in the low-Kunitz soybeans were greater at 81.6% compared to those of conventional full fat soybeans at 74.3%. However, the digestibility of the mean of the indispensable amino acids in the low-Kunitz soybeans were still lower compared with the digestibility of amino acids in soybean meal, which was at 92.3%. Slide 14 So in summary, we saw that the low temperature, low-Kunitz full fat soybeans had a greater SID of amino acids than the low temperature, conventional full fat soybean, but less that the high temperature low-Kunitz and the high temperature conventional full fat soybeans. We observed no differences in the SID of amino acids between high temperature low-Kunitz full fat soybeans and high temperature conventional full fat soybeans. And the digestibility values of these full fat soybeans were not different from soybean meal. Slide 15 In conclusion, this experiment showed that low-Kunitz full fat soybean has a greater SID of amino acids than conventional full fat soybean. However, heat treatment is still necessary to maximize the SID of amino acids in the low-Kunitz full fat soybean, for the digestibility values to reach the same level as soybean meal. Slide 16 Before I end, I would like to acknowledge the funding of this project from Schillinger Genetics. Slide 17 Thank you for your attention. We constantly update our web site for new results of our research, so you're welcome to come and visit at nutrition.ansci.illinois.edu. Have a great day.