The American Soybean Association and the US Soybean Export Council have supported a survey on the quality of the US soybean crop since 1986. These annual crop surveys document quality characteristics compared to previous soybean crops and provides information important to international customers to assist in their purchasing decisions for the upcoming year.
Sample kits were mailed to producers selected so that response distribution would closely match state soybean production. This year 1,903 samples were received. These were analyzed at the University of Minnesota for protein and oil concentration by near-infrared spectroscopy (NIRS) using a Perten DA7250 diode array instrument (Huddinge, Sweden) equipped with calibration equations developed by The University of Minnesota in cooperation with Perten.
Regional and national average protein values were determined by computing weighted averages using state and regional soybean production values, so that average values better represent the crop as a whole. Results of the 2012 soybean quality study are presented in the following tables.
The results show that the average protein concentrations for the 2012 US soybean crop was slightly lower compared to the 2011 US crop and average oil content was slightly higher. The average US soybean protein concentration was 0.5% lower in 2012, at 34.3%, and average oil was virtually unchanged (0.3% higher at 18.5%), when compared with 2011 (Table 2). As is noted in most years, the Western Corn Belt states showed lower protein concentrations than the US crop as a whole. Midsouth and Southeast states commonly produce a soybean crop with higher protein concentrations than other regions.
In 2012, the study was expanded to include amino acid analyses. When expressed as a percent of the protein, the 10 essential amino acids (lysine, methionine, threonine, tryptophan, cysteine, leucine, isoleucine, histidine, phenylalanine and valine) did not appear to vary between regions. (Table 3).
Seth. L. Naeve, James H. Orf and Nick Weidenbenner. 2013. Quality of the United States Soybean Crop-2012. A report prepared for the American Soybean Association and the U.S. Soybean Export Council; January 2m 2013. www.ussec.org/resources/statistics.html and www.soybean.umn.edu