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United States Department of Agriculture

Agricultural Research Service


Location: Peanut Research

2007 Annual Report

1a.Objectives (from AD-416)
Objective 1: Develop a portable sensor and measurement systems to measure moisture in-shell and shelled peanuts during various post harvest processes.

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

Objective 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.

Objective 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.

1b.Approach (from AD-416)
This research will be conducted over a five year period and will consist of laboratory and prototype scale testing. During year 1, runner type peanuts will be dried from various initial moisture contents to a final moisture content of approximately 11% using four levels of incident radiant energy in a laboratory scale catalytic infrared dehydrator. In-shell peanuts will be harvested and divided into five samples approximately 20 kg each. The initial moisture content of each of the samples will be determined using the oven method (ASAE S410.1). As a control, one sample will be dried using conventional forced air curing systems that heat the air 8C above ambient but no higher than 35C. The remaining samples will be dried using four different incident energy levels while recording pod surface temperature. Moisture content will be determined during drying by monitoring the sample mass. Drying will be terminated when the desired mass loss has occurred. The test will be repeated throughout the peanut harvest season, using peanuts with initial moisture contents ranging from 20 to 13%. Each sample will be shelled using a model sheller and kernels separated into commercial sizes to determine milling quality. The shelled peanuts will be subdivided into smaller samples to determine the vigor index, single kernel moisture distribution, and the presence/absence of off flavors. The single kernel moisture distribution will be measured using a Shizouka Seiki CTR-160P.Data will be analyzed using incident energy levels as drying treatments and tests replicated throughout the peanut harvest. The effect of the incident radiant energy on peanut drying time, milling quality, seed germination and vigor, and the incidence of off-flavors will be determined using analysis of variance.

3.Progress Report
Research was continued toward determining the effects and feasibility of storing farmer stock peanuts in low oxygen atmospheres. Efforts continued to develop instrumentation to measure peanut moisture content while still in the shell to reduce labor and cost of monitoring and measuring moisture content during post harvest processing. A project was conducted in collaboration with USDA, AMS to modify peanut grading equipment to reduce the cost and time of official sample evaluation at the first point of sale.

Peanut Curing Management Software Completed and Released. Equations to estimate peanut curing (drying) times and real time estimates of peanut moisture content were evaluated in software written at the National Peanut Research Laboratory by commercial drying facilities. The curing of over 100,000 tons of peanuts was managed using the software during each of the 2005 and 2006 crops with no changes to the prediction equations between seasons. The software has been released for commercial use and operator training sessions held. Users have reported saving approximately 20% of peanut curing costs and improved quality and consistency of peanuts presented for marketing after curing. At an estimated curing cost of $20/ton, this correlates to at least $4/ton of peanuts dried. Assuming that 50% of the peanuts produced in the U.S. were cured using this software, an annual savings of $4 million saved annually in curing costs. NP-306 Action Plan Component 1 (Factors and Processes that Affect Quality) NP-306 Action Plan Problem Statement: Determine influence of post-harvest factors on quality, including storage, handling, grading, and processing.

5.Significant Activities that Support Special Target Populations

6.Technology Transfer

Number of invention disclosures submitted1
Number of web sites managed2
Number of non-peer reviewed presentations and proceedings6
Number of newspaper articles and other presentations for non-science audiences10

Review Publications
Butts, C.L., Faircloth, W.H., Lamb, M.C., Nuti, R.C., Rowland, D., Sorensen, R.B., Guerke, W.R. 2007. Effect of bulk handling on peanut seed quality. Peanut Science. 34:22-26

Last Modified: 4/20/2014
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