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United States Department of Agriculture

Agricultural Research Service


Location: Peanut Research

2006 Annual Report

1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter?
The U.S. peanut industry has identified reducing the cost of production, increasing the food safety of peanut products, improving peanut quality, and improving the health benefits of consuming peanut products as their major goals. Peanut quality is generally defined by flavor, kernel size, and the absence of foreign material and aflatoxin. Adequately determining peanut quality requires that appropriate measurements of physical and chemical properties be made on an adequate and representative sample. Currently, the industry measures kernel size distribution and performs a visual inspection for the presence of aflatoxin-causing molds in a representative sample. The peanut industry needs improved systems to extract samples to measure quality, remove foreign material, detect and manage peanut maturity, dry, handle, and store peanuts.

Peanut market type, cultivar, and environmental conditions during the growing season affect all aspects of peanut quality. There are over twenty peanut cultivars available for production depending on peanut market type the spectrum of disease resistance required. Some cultivars are more determinant than others, changing the distribution of peanut maturity on each plant. Some varieties tolerate various stresses, such as water and disease, better than others. When delivered to a processor, peanuts must be segregated based on quality standards as well as physical properties. Peanuts of the same market type, but different cultivars may be commingled and processed together if their physical properties and shelling characteristics are similar. However, if the physical properties of a cultivar are different from the norm for a particular market type, then it must be segregated and processed separately.

Since 1997, peanut production has moved out of the traditional production areas in some states, the peanut marketing program has changed, and high capacity harvesting equipment has been implemented across the US. However, curing and storage systems have remained relatively unchanged. The majority of peanuts grown are cured in batches ranging from 4-20 t. High capacity drying systems are needed that will match the harvest capacity of farmers yet be economically viable due to the short duration of the harvest each year. Changes in peanut quality occur during all processing, including curing, storage, shelling, blanching and roasting. These changes can adversely affect peanut flavor, shelf life, seed viability, and consumer acceptance. Degradation of crop quality during storage due to improper moisture control, insect damage, and mechanical damage represents an annual monetary loss of $6 million. Sensors and meters to measure moisture content easily while drying and shelling are needed to optimize these processes. Systems for drying and storing peanuts are needed that will minimize excessive moisture loss, improve moisture uniformity and have low initial capital cost are needed.

This project falls within Component 1 “Quality Characterization, Preservation, and Enhancement” of National Program 306, Quality and Utilization of Agricultural Products. This project focuses equally on Components1b, Methods to Evaluate and Predict Quality, and 1d, Preservation and/or Enhancement of Quality and Marketability. It also has a strong emphasis on 1c, Factors and Processes that Affect Quality. The project objectives are:

1. Develop a portable sensor and measurement systems to measure moisture in-shell and shelled peanuts during various post harvest processes.

2. Develop and maintain a database of peanut quality parameters and processing characteristics for commercial peanut varieties.

3. Develop peanut curing, transportation, and storage systems and management processes that maintain quality and minimize unit costs and quality deterioration during post harvest processing.

4. Expand the peanut curing decision support system to include new drying equipment and to support management of inventory from the field into the warehouse.

2.List by year the currently approved milestones (indicators of research progress)
Year 1 (FY 2005) 1. Analyze frequency response data. Develop impedance measurement system and sensor. Conduct calibration tests. 2. Initiate agronomic, physical and chemical properties database from existing UPPT data. Collect data from current year samples. 3. Initiate and conduct laboratory-scale infrared (IR) curing studies. 4. Construct, instrument, and load controlled atmosphere (CA) storage units. 5. Develop drying model and conduct simulation studies.

Year 2 (FY 2006) 1. Modify impedance measurement system and sensor. 2. Update peanut properties database. Analyze data. Collect current crop year data. 3. Analyze curing data. Continue IR curing research. 4. Analyze CA storage data. Continue CA peanut storage research. 5. Calibrate peanut curing decision support system with commercial drying data.

Year 3 (FY 2007) 1. Analyze moisture calibration data. Refine probe and measurement system. Collect data for all market types. 2. Update peanut properties database. Analyze data. Collect data. Develop mining methods. 3. Analyze curing data. Continue IR curing research. 4. Analyze CA storage data. Continue scale model CA storage. Initiate commercial CA storage. 5. Revise decision support system, release to beta testers.

Year 4 (FY 2008) 1. Analyze moisture data. Refine probe. Conduct commercial field studies. 2. Update peanut database. Analyze data. Collect data. 3. Analyze curing data. Conduct prototype/full-scale IR curing research. 4. Analyze CA storage data. Continue scale model and commercial CA storage research. 5. Analyze beta peanut curing decision support system, modify underlying models as necessary.

Year 5 (FY 2009) 1. Final analysis and transfer moisture measurement technology to industry. 2. Continue mining/analysis of peanut properties database. Make database available on line. 3. Final analysis of feasibility of IR peanut curing and transfer to industry. 4. Analyze CA storage data. Transfer technology to industry via publication of guidelines for design and operation. 5. Revise and release peanut curing decision support software.

4a.List the single most significant research accomplishment during FY 2006.
Peanut Curing Decision Support System: The decision support system for managing peanut curing operations released in FY 2005 was revised based on user feedback and released for use by the peanut industry. User feedback of previous version stated that using the decision support system reduced labor, and reduced over drying, and minimized reductions in milling quality thereby reducing the cost of drying peanuts significantly.

4b.List other significant research accomplishment(s), if any.
Completed development of an air volume control valve and procedure to calibrate pneumatic samplers use to obtain official samples for determining peanut value at farmer marketing. Equipment and procedures have been incorporated into Federal-State Inspection Service maintenance procedures in all peanut producing regions of the U.S.

4c.List significant activities that support special target populations.
No activities to report.

4d.Progress report.

5.Describe the major accomplishments to date and their predicted or actual impact.
FY 2005. PECMAN, a decision support system to manage commercial peanut drying facilities was released and meets milestone 4A of the project plan. System users will reduce labor and minimize risk of over drying farmer stock peanuts. Over drying can cost as much as $22/ton. This accomplishment was directed toward Component 1d, Preservation and/or Enhancement of Quality and Marketability of the action plan for NP 306. By improving the management of the peanut curing process, the risk of quality loss during the first and critical post harvest process is minimized.

6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products?
A decision support system to manage commercial peanut curing operations, PECMAN, was released in July 2005. Commercial peanut curing facilities monitor up to 200 dryers simultaneously using seasonal labor. The software incorporates an empirical model published in 2004 to predict drying times for each active peanut dryer and provides sampling schedules. By using the software, commercial facilities can optimize seasonal labor, minimize the risk of over drying, and maximize system use efficiency. The software is usable by most all education levels typically found at the drying facility. As long as batch systems are used for drying peanuts, this software will be applicable.

Guidelines for aerating peanut warehouses to minimize quality loss during farmer stock storage were written based on research results. Guidelines have been incorporated into the American Peanut Shellers Association’s online handbook, “Handling and Storage of Farmer Stock Peanuts” (

Review Publications
Butts, C.L., Faircloth, W.H., Nuti, R.C., Rowland, D. 2006. Bulk seed tenders for handling peanut seed. Georgia Peanut Research Extension Report. 9-13.

Pomes', A., Butts, C.L., Chapman, M. 2006. Quantification of ara h 1 in peanuts: roasting makes a difference. Journal of Clinical and Experimental Allergy. 36:824-830.

Kandala, C., Butts, C.L., Nelson, S.O. 2006. PARALLEL-PLATE SENSORS FOR MEASUREMENT OF MOISTURE CONTENT IN IN-SHELL PEANUTS NON-DESTRUCTIVELY. Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE). Paper number 066041.

Harraz, H., Wang, Y., Butts, C.L. 2006. Dehydration of in-shell peanuts using radio frequency energy with intermittent stirrings. ASABE Paper No. 066048. . American Society of Agri Engineers Special Meetings and Conferences Papers.

Kandala, C., Butts, C.L., Nelson, S.O. 2006. PARALLEL-PLATE SENSORS FOR MEASUREMENT OF MOISTURE CONTENT IN IN-SHELL PEANUTS NON-DESTRUCTIVELY. Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE). Paper No. 66041..

Butts, C.L., Faircloth, W.H., Nuti, R.C., Rowland, D., Lamb, M.C., Guerke, W.R. 2006. The effect of bulk handling on peanut seed quality. American Peanut Research and Education Society Abstracts.

Last Modified: 4/18/2014
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