DR. THOMAS J. BRUMM(*2)
DR. CHARLES R. HURBURGH, JR.(*2)

Quality continues to be an important soybean marketing issue. This report summarizes current knowledge on the following soybean quality topics:

• Protein and oil composition of the 2003 U.S. soybean crop
• The 2003 crop in historical and geographic perspective
• Weather conditions affecting the 2003 cropy
• Programs by growers and U.S. processors to improve quality

The data and analyses in this report are intended to assist customers in the sourcing and use of U.S. soybeans.

Since 1986, Iowa State University (ISU) and the American Soybean Association (ASA) have been surveying the quality of new crop soybean harvests. U.S. soybean producers, representing 30 soybean production states, in response to a mailed request, provided samples of 2003 crop soybeans for analysis. Samples received by November 7, 2003 were analyzed for protein and oil contents using an Infratec near-infrared instrument (Foss North America, Eden Prairie, Minn.). A geographically distributed subset was sent to the University of Missouri for amino acid analysis. From other sources, data on the yield and physical quality (U.S. Grade factors) of U.S. soybeans have been collected. Data were organized by state and region (groups of states). Weather data for the 2003 growing season were collected to demonstrate the impact of unusual environment on soybean composition.

The United States produced 2.468 billion bushels (66.9 million metric tons) of soybeans in 2003, according to the October 14, 2003 USDA production estimates (USDA, 2003). This is a decrease of 6.9 percent from 2002, and the lowest since 1996. The average soybean yield was 34.0 bushels per acre, down from 37.5 bushels per acre in 2002 and the lowest per acre yield since 1989. An estimated 72.5 million acres (29 million hectares) of soybeans were harvested, a 1% increase from 2002. Table 1 summarizes production statistics for the 2003 crop, by state and growing region.

*1:Prepared for the American Soybean Association Quality Mission to Japan, November 15-17, 2003
*2:Assistant Professor and Professor, respectively, Agricultural and Biosystems Engineering Department, Iowa State University, Ames, IA 50011

Composition data are given in Table 2. Average U.S. protein and oil contents for 2003 were 35.65% and 18.66% respectively (on a 13% moisture basis). These are slightly above the long-term U.S. averages of 35.42 % protein and 18.60 % oil. The soybeans from the 2003 crop will produce, on average, 43.8 lbs of 48% protein meal and 10.9 lbs of oil per bushel.

The variability (standard deviation) within states, regions, and the U.S. was substantially higher than in 2002. This means that regional or other forms of geographic buying for higher protein and oil will yield more uncertain results. The higher variability was particularly pronounced in the oil, with a standard deviation of 1.02 percentage points as compared to an 18-year average of 0.89 percentage points. The north to south protein pattern (lower north, higher south) was present, but was not consistent. For example, Minnesota soybeans were very close to the national averages in protein and higher in oil. This is very unusual; it has happened only one other time (1991). Likewise, Midsouth soybeans were lower in protein than those in the Eastern Corn Belt. Harvest temperatures were at or above average throughout harvest, so there should be little frost damaged soybeans which cause oil refining problems. Expect moistures under 12% this year, below the historical average. Soybeans will be small, which may require resetting of cracking rolls and other equipment to prevent abnormal oil loss into meal.

Weather Conditions in 2003

The severity of dry weather in the U.S. is shown in Figure 1. The U.S. Drought Monitor is a visual summary of moisture-related conditions averaged across a broad array of time scales and impact indicators (NDMC, 2003). It approximates drought-related impacts that respond to precipitation.

The Western U.S. has experienced severe drought for two years, but in 2003 the dry area expanded into the Western Corn Belt. The timing of dry weather is also important; in soybean growing areas the dry period was in August and September which are crucial for pod filling. Most central U.S. areas were actually above normal for moisture until early August.

There have been many studies relating soybean protein and oil content to environmental conditions. Table 3 is a qualitative summary of soybean composition in response to weather and non-agronomic variables (Westgate, et al., 1999). In 2003, the crop results reinforced previous findings about the timing effect of dry weather.

Soybean yields and acreage, which increased steadily in the 1990s, appear to have stabilized in recent years. Table 4 shows a combination of USDA production and survey composition data. The yield, protein and oil data is shown graphically in Figure 2. In the 1990s, yields increased by 0.5 bushels/acre/year, with little change in average protein and oil content. In recent years, there has been little yield increase but constant protein and oil levels. Breeding programs continue to emphasize yield, apparently without creating quality loss. The net result is a steady increase in the production of protein and oil per unit of area (Figure 3). From a consumer perspective, this has meant a steadier, more abundant supply from the same inputs (land, seed, fertilizer and so on). The overall supply impact of the 18-year composition data is in Figure 4.

The regional north-to-south protein trend has been reasonably consistent over the 18 years of the survey. Figures 4 and 5 show the regional averages for these years. The regional differences for protein were much larger than those for oil, but the different growing seasons created more overall change in oil than in protein. The range among individual samples in any state was about twice as large as the range across regions or years. This means that buying patterns established to capture forecasted differences in composition without testing will have a large margin of error, and therefore cannot provide substantial premiums to growers or handlers.

The processing chart in Figure 6 shows the combinations of protein and oil content that will produce 47.5% to 48.5% protein soybean meal. Only once (1997) did U.S. soybeans fall to the left of the optimal area, shown by the shading. Soybeans from individual states and regions often fall to the far right, above 48.5% meal, and the U.S. averages are regularly in the middle of this area. In 2003, the U.S. average falls almost exactly on the 18-year average of the survey.

The USDA Grain Inspection Packers and Stockyards Administration (GIPSA) provides a variety of optional services for soybean inspections (GIPSA, 2003a) as described below (from the GIPSA website):

To provide information concerning intrinsic properties of soybeans related to user economics, GIPSA offers protein and oil testing of soybeans as an optional service. Protein and oil contents determine the amount and quality of end products, soybean meal and soybean oil, that can be produced from a bushel of raw soybeans. Upon request, GIPSA tests soybeans for their protein and oil content using Near-infrared Transmittance (NIRT). Using NIRT allows GIPSA to provide a simple, timely, repeatable and cost effective means of determining the oil and protein content in soybeans.

The Soybean Cracked Seedcoats assessment was added to GIPSA's optional quality assessment services in response to increasing trade requests. The purpose of this test is to determine the percent of cracked seedcoats of sound soybeans. The determination is made on approximately 125 grams after the removal of foreign material and damaged kernels. Soybeans with cracked seedcoats are sound soybeans which have readily discernible cracked seedcoats, sound soybeans which have all or part of the seedcoat removed, or sound soybeans which are % or more of a whole soybean.

The Soybean Seed Count assessment was added to GIPSA's optional quality assessment services in response to increasing trade requests for the service. GIPSA reports the number of whole soybeans contained in a specified weight. The determination of the seed count per gram is made on approximately 25 grams after the removal of foreign material and non-whole soybeans. This is then mathematically converted to the requested number per weight.

The Soybean Seed Sizing assessment was added to GIPSA's optional quality assessment services in response to increasing trade requests for the service. Seed sizing is a measurement of the percentage of soybeans passing through or remaining on top of a sieve size specified by the applicant for service. The test is run on a sample of approximately 125 grams after the removal of foreign material.

The Soybean White Hilum assessment was added to GIPSA's optional quality assessment services in response to increased trade requests. The purpose of this test is to determine the percent of whole soybeans with a clear white hilum. Upon request, tests for other hilum color (buff, brown, etc.) can be provided. The determination is made on approximately 125 grams after the removal of foreign material and non-whole soybeans.

Any of these can be requested at an export inspection. The protein and oil analysis can be particularly useful for buyers with contract specifications on composition. The GIPSA tests are done at the time of vessel loading and therefore can be used like any of the other Official Grade factor tests to control variation in the quality being loaded. There are breakpoints and other parameters for use in loading to protein and/or oil specifications.

The GIPSA data is not separated by export location. The Gulf South ports are generally served by the Corn Belt state areas along the Mississippi-Ohio-Illinois-Missouri river system. Pacific Northwest (PNW) ports are more likely to receive grain from the states classified as Western Corn Belt in the survey. Export quality at any port will tend to mirror the quality of production areas that serve it. Over the 18 years of the survey, the percentage of U.S. crop produced in the Western Corn Belt has gradually increased from about 40% to just over 50%. This shift is toward areas of potentially lower protein content. The previous data showing a constant level of U.S. average protein and oil is a real credit to the U.S. soybean genetics industry when viewed in the context of this geographic shift in production. However, shipments from PNW ports will tend to be of lower protein than those from Gulf South ports.

The U.S. domestic soybean market is beginning to create incentives for improving protein and oil contents. At least four major soybean processors have followed the lead of AgProcessing Inc. (AGP), in offering some form of premium for higher composition levels. The AGP premium scale has been described in the last two years' discussion papers (Brumm and Hurburgh, 2002; Hurburgh, 2001). The AGP scale rewards above average oil content, and then provides a protein premium in cases where both the oil and protein are above average (AGP, 2003). Other strategies in use are minimum levels with discounts for below standard composition, processor subsidy for producers to purchase varieties from an approved list, and direct production volume or acreage contracts. The variety list concept has advantages in that testing of each delivery is not required; the program assumes that the varieties on the list will always be above average in composition for the year. Variety trial data support that assumption; the relative ranking of varieties stays the same regardless of the overall changes created by year-to-year weather conditions. In all cases, the objective of the processor is to raise the overall average composition of beans purchased. It is not necessary to segregate high protein and/or oil beans for separate processing runs. A solvent extraction plant recovers the amounts of protein and oil present on a mass balance basis.

The potential for incrementally increasing average oil and protein contents is shown by the example data in Figure 7. This was a situation where we measured protein, oil and grain yield for samples arriving at processing plants. The data is referenced to the average at the respective plant location. Samples falling in the upper right quadrant are above average in both grain yield and quality. Consistently 20% of data points fall in this category, which means that a producer could increase composition by both choosing those varieties and cultural practices and by eliminating the situations in lower left (below average yield, below average composition). The total of protein and oil is the best measure of value to use, rather than either component alone.

The United Soybean Board has begun two programs to increase producer awareness and improve measurement methods for soybean composition. The Select Yield and Quality program (SYQ) is a producer education effort targeted at the Western Corn Belt, to increase understanding of the possibilities for improved composition with improved or constant grain yield (USB, 2003). The Soybean Quality Traits program (SQT) is a research oriented association of analytical laboratories and plant breeders, to create uniform, standardized methods for measuring soybean quality traits (protein, oil, fatty acid profile, amino acid profile).

SYQ is a print and media education program targeted at processors, to illustrate the benefits of including composition in pricing policies, and at growers, to demonstrate the potential for composition increase without yield loss. In the growers' case, USB is also explaining the benefits to U.S. competitiveness of increasing composition with or without price incentives, as South American production shifts toward the equator (probable higher protein). The major emphasis is on variety selection. Price incentives must expand to support the information in order for SYQ to be a long-term success.

SQT has organized approximately 20 analytical laboratories, 10 plant breeding organizations (private and public) and three USDA labs for proficiency evaluation of fundamental reference chemical methods. Iowa State University is providing the coordination and standardization for rapid method calibration - in this case for near infrared measurements. Thirteen models of near infrared analyzers are represented in the SQT program. The first SQT report on accuracy of laboratory methods, and on the potential for accurate NIR measurements across models will be completed in 2004. The plant breeding industry has committed to providing a continuing supply of samples representing new genetics for improved soybean quality traits. The overall organizer of SQT is the American Oil Chemists Society. Funding is being provided by the U.S. soybean producers, through the United Soybean Board.

The 2003 U.S. soybean crop has average protein (35.7%) and oil (18.7%) contents. The variability in protein and oil content was quite high across and within soybean growing regions. Yields and total production were down sharply from 2003 due mainly to drought conditions in the Western Corn Belt. There are continuing efforts on the part of many U.S. groups to improve soybean quality through education, price premiums and inspections. If widespread incentives develop in U.S. markets, importers will need to respond in a competitive way.

AGP, 2003. Soybean value pricing - component premium program. http://www.agp.com/premiums. Ag Processing, Inc., Omaha, NE. 11/10/03.

Brumm, T.J., and C.R. Hurburgh, Jr., 2002. Quality of the 2002 soybean crop from the United States. American Soybean Association Asia Quality Seminars, December 2-13, 2002. http://www.abe.iastate.edu/soysurvey/2002-US-SB-Quality.pdf. 11/10/2003.

GIPSA, 2003a. Optional Quality Assessment Services. http://www.usda.gov/gipsa/programsfgis/inspwgh/other/other.htm. USDA Grain Inspection, Packers and Stockyards Administration, Washington, DC. 10/30/2003.

GIPSA. 2003b. 2002 U.S. Grain Exports: Quality Report (Soybeans). http://www.usda.gov/gipsa/pubs/02ex/soybeans.pdf. USDA Grain Inspection, Packers and Stockyards Administration, Washington, DC. 10/30/2003

Hurburgh, C.R., Jr. 2001. Quality of the 2001 soybean crop from the United States. American Soybean Association Asia Quality Seminar, December 6, 2001. http://www.iowagrain.org. 11/21/2002.

NDMC, 2003. U.S. Drought Monitor (September 2, 2003). http://www.drought.unl.edu/dm/archive/2003/drmon0902.htm. National Drought Mitigation Center, University of Nebraska-Lincoln, Lincoln, NE. 11/10/03.

USB, 2003. Soybean Checkoff Encourages Farmers to Take a New Approach to Variety Selection. http://www.unitedsoybean.org/news/nr20030725.htm. United Soybean Board, Chesterfield, MO. 11/10/03.

USDA, 2003. Crop Production 2003 (Cr Pr 2-2, October, 2003). http://jan.mannlib.cornell.edu/reports/nassr/field/pcp-bb/2003/crop1003.pdf. USDA National Agricultural Statistics Service, Washington, D.C. 10/14/2003.

USDA. 2002c. Track records of United States crop production. http://www.usda.gov/nass/pubs/trackrec. USDA National Agricultural Statistics Service, Washington, D.C. 11/21/2002.

Westgate, M.E., E. Piper, W.D. Batchelor, and C.R. Hurburgh, Jr. 1999. Effects of cultural and environmental conditions during soybean growth on nutritive value of soy products. Proc. Global Soy Forum, American Soybean Association, St. Louis, MO.

Figure 1. U.S. Drought Monitor as of September 2, 2003.

Figure 3. U.S. Production of Soybean Protein and Oil per unit area.

Figure 5. Historical U.S. Soybean Oil Content by Region.

Figure 7. Identification of High-Value Soybeans.

Table 2. United Soybean Board/American Soybean Association 2003 Soybean Quality Survey Data.

Table 3. Soybean composition response to weather and non-agronomic variables.

Table 4. Historical Summary of Yield and Quality Data for U.S. Soybeans.

Table 5. Summary of GIPSA Grain Inspection Data for Soybeans.