Source: Schillinger Genetics, Inc. submitted to
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
Funding Source
Reporting Frequency
Accession No.
Grant No.
Project No.
Proposal No.
Multistate No.
Program Code
Project Start Date
May 1, 2008
Project End Date
Apr 30, 2009
Grant Year
Project Director
Schillinger, J. A.
Recipient Organization
Schillinger Genetics, Inc.
4401 Westown Parkway, Ste 225
West Des Moines,IA 50266
Performing Department
Non Technical Summary
Commercial soybeans require heat processing to deactivate anti-nutrition factors/enzymes. Schillinger Seed has developed a new soybean free of the key anti-nutrition Kunitz Tyrpsin Inhibitor (SKTI-Null). This new SKTI-Null) soybean presents the opportunity for ambient or cold processing of soybeans for use in food and feed. The elimination of heat processing eliminates the need of a signifcant amount of processing energy and greatly reduces the compexity of processing. The project will produce samples of cold/ambient processed soybean meal for testing in feeding trials with swine and poultry. A control lot of SKTI-Active soybeans will also be produced and fed as a reference. The feeding trials will also benchmark against conventional commercial soybean meal. Lab analysis will validate the profile of all the raw soybeans and the meals fed in the feeding trials. The results of the feeding trails will be analysed for impact on feed conversion and weight gain. Assuming success with SKTI-Null cold processed meal we plan to advance to pre-commercial trials the following year in a Phase II project. Anticipated benefits include lower cost protein feed and food production and new opportunity for decentralized processing of soybeans in local facilities near sources or markets. Further benefits could be improved amino acid quality as a result of the elimination of heat exposure.
Animal Health Component
Research Effort Categories

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
Goals / Objectives
Commercial soybeans contain a number of anti-nutritional factors, the Soybean Kunitz Trypsin Inhibitor (SKTI) being the major factor in blocking the digestion of proteins. This limitation is typically overcome in conventional soy processing by the application of heat to deactivate the SKTI enzyme. Schillinger Seed has developed new varieties of high protein soybean that are free of the SKTI. These SKTI-Null soybeans present a significant new opportunity in soybean processing because heat processing is no longer required to deactivate the enzyme. We propose that the SKTI-Null soybeans can be processed using ambient or cool temperature processing to produce highly digestible soybean food ingredients and feed components. This project proposes to process the SKTI-Null soybeans, through two distinct ambient processes, to yield distinct products that could be of interest to both the food ingredient and animal feed sectors. The processes used are non-thermal techniques for food and feed preparation, meeting the USDA FY 2008 Research Priority #4 objectives for the Development of specialty products or processes using non-thermal techniques for food preservation. The products of these processes will be compared to similar products from conventional SKTI-Active soybeans by both analytical chemistry and in feeding studies with poultry and young swine. The analytical chemistry will validate the nutritional composition and levels of SKTI in the various meals produced. The feeding studies will test the impact on growth in animals and form the basis for initial calculations on the economics and value of the products compared to conventional solvent-extracted, heat-treated soybean meal. The feeding trails will be conducted in collaboration with leading university animal nutritionists that have previously cooperated with Schillinger Seed, bringing expertise and credibility to the studies. This project will complete the needed research and development on the processes and measure the nutrition of the products to validate the concept and lay the foundation for Phase II. Phase II work will include scaling up to commercial processes and producing larger quantities of preferred meals for wider application in feeding studies and initial food ingredient development. Combining the benefits of SKTI-Null soybeans and ambient temperature processing to create a new generation of soy ingredients for food and feed use by means that require less energy use than conventional soy products will present new opportunity for US agriculture.
Project Methods
SKTI-Null soybeans and a commercially competitive SKTI soybean variety (SS 435) will each be processed through two new ambient processes to yield soybean meals suitable for food applications and acceptable for feeding studies. The roller process will result in a full-fat soybean meal, the cold press process in a partially-defatted meal. Full lab analysis of the resultant meals will be performed to characterize the material sufficiently. To assess the acceptability of the SKTI-Null soybeans in human and animal nutrition, a set of two feeding trails will be completed with young swine and poultry. The feeding trials will include a fifth variable, a defatted soy meal that will serve as the commercial reference. This procedure will assure that the results can be benchmarked against the most common form of soybean meal used commercially, a meal that has also been used in previous Schillinger Seed sponsored feeding trials. The results of the processing and feeding trials will then be assessed and recommendations made for advanced development and/or validation of the processes on larger scale equipment within the context of a Phase II project as soon as 2009-2010.

Progress 05/01/08 to 04/30/09

OUTPUTS: Trypsin inhibitors are identified as the most significant antinutritional factor in raw soybeans. Schillinger Genetics has developed soybean lines free of the primary trypsin inhibitor, the Kunitz type. The thesis tested in this project was that the elimination of the Soybean Kunitz Trypsin Inhibitor (SKTI) to create an SKTI-Nulls soybean would improve swine feeding performance. Two soybean varieties, one conventional, and one SKTI-Null were grown, harvested, and dehulled to yield a full-fat feed substrate. Then 1/3 of each varietal lot was heat-processed through an andogenous extruder to denature any residual SKTI and milled to create a full-fat feed meal. Another 1/3 was simply cold-process roller milled down to feed meal granulation using ambient processing to produce a full-fat product in which enzymes would remain active. The final 1/3 of the two lots was subjected to a cold press process with a goal to produce an enzyme-active partially defatted feed meal. This process was unsuccessful and this option had to be abandoned. The resulting four meals were formulated into weanling pig rations for digestibility studies. A fifth ration was formulated using conventional, commercial hexane extracted meal to serve as a reference. A sixth ration nitrogen-free ration was also formulated. The six rations were fed in November/December 2008 in an experiment conducted to determine the standardized ileal digestibility (SID) of amino acids in 4 sources of full fat soybeans (FFSB) and in 1 source of soybean meal (SBM). Pigs were arranged in a replicated 6 x 6 Latin square design with 6 diets and 6 periods per square. Five diets were prepared using each of the soybean sources as the only source of AA in the diet. An N-free diet was also included in the experiment to measure basal endogenous losses of AA. Twelve weanling barrows were fitted with a T-cannula in the distal ileum. Samples were collected, frozen, and analyzed for SID. PARTICIPANTS: Dr John Schillinger, President of Schillinger Genetics, Inc. served as principle investigator and project director. Joe Colyn, P.Ag., Originz, LLC, collaborated as the co-principle investigator and managed the processing of the soybeans into the feed meals. Dr. Hans Stein, Associate Professor, Animal Nutrition, University of Illinois, Champaign-Urbana, IL designed and managed the feeding trials and the analysis of the samples. Kurtis Goebel, Graduate Student in Dr Stein's lab conducted the feeding trails and analysis. Collaborating in the feed meal preparation, Dr. Karl Weingartner and Danny Erickson at UIUC National Soybean Research Laboratories' Ag Bioprocessing Lab supported the extrusion cooking of the heat treated meal. Gerald "Shep" Shepetunko, Shepetunko Farms, collaborated by provided access to the Komet Press technology for cold pressing. Paul Lang, President, Natural Products, Inc. colaborated in supporting the production of the cold process meals. TARGET AUDIENCES: The key target audience for this work is all people in need of quality plant protein in their diets, directly or as fed through poultry, swine, fish or other animals. This audience will benefit when soybeans no longer require heat processing by virtue of the elimination of significant antinutrional enzymes including the Soybean Kunitz Trypsin Inhibitor. More directly the livestock feeding industry is expected to first benefit from Soybean Kunitz Trypsin Inhibitor Null soybeans through reduced processing enery needs and simplified feed formulation. PROJECT MODIFICATIONS: Our attempt to cold-press dehulled cracked soybeans through the Komet press was unsuccessful. We attribute this to a combination of high moisure and lack of fiber in the substrate. Our hope was that by pressing out some of the oil we could capture value from that oil. As this is unlikely we will advance to targetting higher value feed markets that require high energy content provided by the full-fat meals, in particular markets that prefer vegetable oil over rendered fat and grease products. In fact this keeps processing even simpler and offers better opportunity, by eliminating pressing equipment. The projects goals of testing the impact of cold/ambient processing of Soybean Kunitz Trypsin Inhibitor Null soybeans was not compromised as the full-fat meals met this need in the feeding trial matrix.

The 2 cold-processed full fat soybean meals (FFSB) had lower SID values for all indispensable AA than the 2 extruded FFSB and SBM. The SID values for all indispensible AA except Tryptophan were greater (P < 0.05) in the cold-processed FFSB SKTI-Null than in the cold-processed FFSB conventional, but the SID of AA in the 2 extruded meals and SBM were not different. Results of this experiment show that a reduction of the TIU from 35.4 to 23.5 TIU/mg will improve the SID of AA, but this reduction is not sufficient to completely ameliorate the negative impact of the Kunitz trypsin inhibitors. Results also show that the SID of AA in extruded FFSB is similar to that in de-hulled SBM. As described above in the feeding trial results, the elimination of the Kunitz trypsin inhibitor is not sufficient to eliminate the need for heat processing in soybeans. Other antinutritional factors still require heat deactivation before optimum digestion is achieved, it appears. To advance the opportunity for the elimination of heat processing of soybeans there is a need to address the present of anti-nutritional factors beyond the Soybean Kunitz Trypsin Inhibitor. Other trypsin inhibitors including the Bowman-Birk and possibly other heat-labile anti-nutritional factors and complex sugar (oligosaccharide) that may also need to be eliminated or reduced in soybeans before ambient processing or direct feeding of whole raw soybeans and soybean products with optimal digestibility will be realized. Schillinger Genetics continues to advance the genomics, selection and breeding of new soybean lines for use in food and feed application. Advanced lines have been identified with further reduction of trypsin inhibitors and other anti-nutrition factors and they should be evaluated through ambient processing and into feeding trials similar to those of this study. Schillinger Genetics has continued to make strides in the now almost two years since the thesis for this research proposal was conceptualized and executed. Schillinger has continued to screen for the reduction of all Trypsin Inhibitors and now performs quantitative assays for TIUs. We have verified that the total TIU reduction to 62% of commodity soybeans can be attributed to the Kunitz Inhibitor elimination in the SKTI-Null variety and that further reductions to 37-41% (vs. commodity) in the Schillinger next generation varieties is significant progress in the elimination of all/most of the anti-nutritional factors. By 2010 Schillinger expects to have another selection of RTI (Reduced Trypsin Inhibitor) soybean lines. And these lines are agronomically competitive. Farm-gate value of USA soybean production exceeds $18 billion annually for the ~ 3 billion bushel crop. Typical soybean processing facilities, all employing heat processes, have operating costs in the range of $0.44-0.52/bushel. If only 1% of this crop adopts cold processing technology and total processing costs is reduced by half to $0.22-0.26/bu for 30,000,000 bushels the benefit in cost reduction could be $6.6 - $7.8 million dollars. The opportunity is significant, particularly in a world where energy prices are rising.


  • Goebel, K.P., and H. H. Stein, 2009. Ileal digestibility of amino acids in conventional and low-Kunitz soybean products fed to weanling pigs (prepublication draft available from the authors, The plan is to submit this to the Journal of Animal Science or the Canadian Journal of Animal Science for peer reviewed publication. An abstract of this will also be presented at the Annual Animal Science Meeting in Montreal, Canada in July 2009.)